Promethazine

Generic name: Pronounced as (proe meth' a zeen)
Brand names
  • Phenergan®
  • Promethegan® Suppository
  • Remsed®
Click on drug name to hear pronunciation

Medical Content Reviewed By HelloPharmacist Staff

Last Revised - 06/15/2017

Promethazine may cause breathing to slow or stop, and may cause death in children. Promethazine should not be given to babies or children who are younger than 2 years old and should be given with caution to children who are 2 years of age or older. Combination products containing promethazine and codeine should not be given to children younger than 16 years old. Promethazine should not routinely be used to treat vomiting in children; it should only be used in specific cases when a doctor decides that it is needed. Tell your child's doctor if your child has any condition that affects his/her breathing such as lung disease, asthma, or sleep apnea (stops breathing for short periods of time during sleep). Tell your doctor or pharmacist about all the medications your child is taking, especially barbiturates such as phenobarbital (Luminal), medications for anxiety, narcotic medications for pain, sedatives, sleeping pills, and tranquilizers. Call your child's doctor immediately and get emergency medical treatment if your child has difficulty breathing, wheezes, slows or pauses in breathing, or stops breathing.

Talk to your doctor about the risks of giving promethazine to your child.

Promethazine is used to relieve the symptoms of allergic reactions such as allergic rhinitis (runny nose and watery eyes caused by allergy to pollen, mold or dust), allergic conjunctivitis (red, watery eyes caused by allergies), allergic skin reactions, and allergic reactions to blood or plasma products. Promethazine is used with other medications to treat anaphylaxis (sudden, severe allergic reactions) and the symptoms of the common cold such as sneezing, cough, and runny nose. Promethazine is also used to relax and sedate patients before and after surgery, during labor, and at other times. Promethazine is also used to prevent and control nausea and vomiting that may occur after surgery, and with other medications to help relieve pain after surgery. Promethazine is also used to prevent and treat motion sickness. Promethazine helps control symptoms, but will not treat the cause of the symptoms or speed recovery. Promethazine is in a class of medications called phenothiazines. It works by blocking the action of a certain natural substance in the body.

Promethazine comes as a tablet and syrup (liquid) to take by mouth and as a suppository to use rectally.When promethazine is used to treat allergies, it is usually taken one to four times daily, before meals and/or at bedtime. When promethazine is used to relieve cold symptoms, it is usually taken every 4 to 6 hours as needed. When promethazine is used to treat motion sickness, it is taken 30 to 60 minutes before travel and again after 8 to 12 hours if needed. On longer trips, promethazine is usually taken in the morning and before the evening meal on each day of travel. When promethazine is used to treat or prevent nausea and vomiting it is usually taken every 4 to 6 hours as needed. Promethazine may also be taken at bedtime the night before surgery to relieve anxiety and produce quiet sleep. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take promethazine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Promethazine suppositories are for rectal use only. Do not try to swallow the suppositories or insert in any other part of your body.

If you are taking promethazine liquid, do not use a household spoon to measure your dose. Use the measuring spoon or cup that came with the medication or use a spoon made especially for measuring medication.

To insert a promethazine suppository, follow these steps:

  1. If the suppository feels soft, hold it under cold, running water for 1 minute. Remove the wrapper.

  2. Dip the tip of the suppository in water.

  3. Lie down on your left side and raise your right knee to your chest. (A left-handed person should lie on the right side and raise the left knee.)

  4. Using your finger, insert the suppository into the rectum, about 1/2 to 1 inch (1.25 to 2.5 centimeters) in children who are 2 years of age older and 1 inch (2.5 centimeters) in adults. Hold it in place for a few moments.

  5. Stand up after about 15 minutes. Wash your hands thoroughly and resume your normal activities.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking promethazine,

  • tell your doctor and pharmacist if you are allergic to promethazine, other phenothiazines (certain medications used to treat mental illness, nausea, vomiting, severe hiccups, and other conditions) or any other medications. Also tell your doctor and pharmacist if you have ever had an unusual or unexpected reaction when you took promethazine, another phenothiazine, or any other medication. Ask your doctor or pharmacist if you do not know if a medication you are allergic to is a phenothiazine.

  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements and herbal products you are taking or plan to take. Be sure to mention any of the following: antidepressants ('mood elevators') such as amitriptyline (Elavil), amoxapine (Asendin), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Adapin, Sinequan), imipramine (Tofranil), nortriptyline (Aventyl, Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil); antihistamines; azathioprine (Imuran);barbiturates such as phenobarbital (Luminal); cancer chemotherapy; epinephrine (Epipen); ipratropium (Atrovent)medications for anxiety, irritable bowel disease, mental illness, motion sickness, Parkinson's disease, seizures, ulcers, or urinary problems; monoamine oxidase (MAO) inhibitors such as isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and selegiline (Eldepryl, Emsam, Zelapar); narcotics and other pain medication; sedatives; sleeping pills;and tranquilizers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

  • tell your doctor if you have or have ever had an enlarged prostate (a male reproductive gland); glaucoma (a condition in which increased pressure in the eye can lead to gradual loss of vision); seizures; ulcers; blockage in the passage between the stomach and intestine; blockage in the bladder; asthma or other lung disease; sleep apnea; cancer;any condition that affects the production of blood cells in your bone marrow; or heart or liver disease. If you will be giving promethazine to a child, also tell the child's doctor if the child has any of the following symptoms before he or she receives the medication: vomiting, listlessness, drowsiness, confusion, aggression, seizures, yellowing of the skin or eyes, weakness, or flu-like symptoms. Also tell the child's doctor if the child has not been drinking normally, has had excessive vomiting or diarrhea, or appears dehydrated.

  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking promethazine, call your doctor.

  • talk to your doctor about the risks and benefits of taking promethazine if you are 65 years of age or older. Older adults should not usually take promethazine because it is not as safe as other medications that can be used to treat the same conditions.

  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking promethazine.

  • you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you. If you are giving promethazine to a child, watch the child to be sure he or she does not get hurt while riding a bike or participating in other activities that could be dangerous.

  • ask your doctor about the safe use of alcohol while you are taking this medication. Alcohol can make the side effects of promethazine worse.

  • plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, and sunscreen. Promethazine may make your skin sensitive to sunlight.

Unless your doctor tells you otherwise, continue your normal diet.

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

  • Promethazine can cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

    • dry mouth

    • drowsiness

    • listlessness

    • difficulty falling asleep or staying asleep

    • nightmares

    • dizziness

    • ringing in ears

    • blurred or double vision

    • loss of coordination

    • nausea

    • vomiting

    • nervousness

    • restlessness

    • hyperactivity

    • abnormally happy mood

    • stuffy nose

    • itching

  • Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:

    • wheezing

    • slowed breathing

    • breathing stops for a short time

    • fever

    • sweating

    • stiff muscles

    • decreased alertness

    • fast or irregular pulse or heartbeat

    • faintness

    • abnormal or uncontrollable movements

    • hallucinations (seeing things or hearing voices that do not exist)

    • confusion

    • overwhelming or unmanageable fear or emotion

    • seizures

    • uncontrollable shaking of a part of the body

    • unusual bruising or bleeding

    • sore throat, fever, chills, and other signs of infection

    • uncontrolled eye movements

    • tongue sticking out

    • abnormal neck position

    • inability to respond to people around you

    • yellowing of the skin or eyes

    • rash

    • hives

    • swelling of the face, eyes, lips, tongue, throat, arms, hands, feet, ankles, or lower legs

    • hoarseness

    • difficulty breathing or swallowing

  • If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

  • Promethazine may cause other side effects. Call your doctor if you experience any unusual problems while you are taking this medication.

Keep this medication in the carton or container it came in, tightly closed, and out of reach of children. Store promethazine tablets and liquid at room temperature and away from excess heat and moisture (not in the bathroom). Store promethazine suppositories in the refrigerator. Protect the medication from light.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • difficulty breathing

  • slowed or stopped breathing

  • dizziness

  • lightheadedness

  • fainting

  • loss of consciousness

  • fast heartbeat

  • tight muscles that are difficult to move

  • loss of coordination

  • continuous twisting movements of the hands and feet

  • dry mouth

  • wide pupils (black circles in the middle of the eyes)

  • flushing

  • nausea

  • constipation

  • abnormal excitement or agitation

  • nightmares

Keep all appointments with your doctor.

Promethazine can interfere with the results of home pregnancy tests. Talk to your doctor if you think you might be pregnant while you are taking promethazine. Do not try to test for pregnancy at home.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking promethazine.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

  • Prometh® VC Syrup (containing Phenylephrine, Promethazine)

Drug Interaction
Moxifloxacin Moxifloxacin The risk or severity of QTc prolongation can be increased when Promethazine is combined with Moxifloxacin.
Montelukast Montelukast The metabolism of Montelukast can be decreased when combined with Promethazine.
Leflunomide Leflunomide The metabolism of Leflunomide can be decreased when combined with Promethazine.
Delavirdine Delavirdine Promethazine can cause a decrease in the absorption of Delavirdine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Nevirapine Nevirapine The metabolism of Nevirapine can be increased when combined with Promethazine.
Dolasetron Dolasetron The metabolism of Dolasetron can be decreased when combined with Promethazine.
Anagrelide Anagrelide The risk or severity of QTc prolongation can be increased when Promethazine is combined with Anagrelide.
Bisacodyl Bisacodyl The therapeutic efficacy of Bisacodyl can be decreased when used in combination with Promethazine.
Calcium Carbonate Calcium Carbonate Calcium carbonate can cause a decrease in the absorption of Promethazine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Candesartan Candesartan The metabolism of Candesartan can be decreased when combined with Promethazine.
Cilostazol Cilostazol The metabolism of Cilostazol can be decreased when combined with Promethazine.
Clopidogrel Clopidogrel The metabolism of Clopidogrel can be decreased when combined with Promethazine.
Diphenoxylate Diphenoxylate The risk or severity of adverse effects can be increased when Promethazine is combined with Diphenoxylate.
Erythromycin and Sulfisoxazole Erythromycin and Sulfisoxazole The risk or severity of QTc prolongation can be increased when Promethazine is combined with Erythromycin.
Estrogen and Progestin (Oral Contraceptives) Estrogen and Progestin (Oral Contraceptives) Conjugated estrogens may decrease the excretion rate of Promethazine which could result in a higher serum level.
Fenofibrate Fenofibrate Fenofibrate may decrease the excretion rate of Promethazine which could result in a higher serum level.
Guanfacine Guanfacine The risk or severity of adverse effects can be increased when Guanfacine is combined with Promethazine.
Magnesium Hydroxide Magnesium Hydroxide Promethazine can cause a decrease in the absorption of Magnesium hydroxide resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium Oxide Magnesium Oxide Promethazine can cause a decrease in the absorption of Magnesium oxide resulting in a reduced serum concentration and potentially a decrease in efficacy.
Mycophenolate Mycophenolate Mycophenolic acid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Naratriptan Naratriptan The risk or severity of adverse effects can be increased when Naratriptan is combined with Promethazine.
Olsalazine Olsalazine Olsalazine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Paregoric Paregoric The risk or severity of adverse effects can be increased when Promethazine is combined with Morphine.
Penbutolol Penbutolol The serum concentration of Acebutolol can be increased when it is combined with Promethazine.
Pentazocine Pentazocine The risk or severity of adverse effects can be increased when Promethazine is combined with Pentazocine.
Polyethylene glycol-electrolyte solution (PEG-ES) Polyethylene glycol-electrolyte solution (PEG-ES) The therapeutic efficacy of Polyethylene glycol can be decreased when used in combination with Promethazine.
Potassium Potassium Potassium may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Prednisone Prednisone Prednisone may decrease the excretion rate of Promethazine which could result in a higher serum level.
Psyllium Psyllium The therapeutic efficacy of Plantago seed can be decreased when used in combination with Promethazine.
Ranitidine Ranitidine The metabolism of Promethazine can be decreased when combined with Ranitidine.
Reserpine Reserpine Reserpine may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Rizatriptan Rizatriptan Rizatriptan may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Sumatriptan Sumatriptan Sumatriptan may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Tacrolimus Tacrolimus Tacrolimus may decrease the excretion rate of Promethazine which could result in a higher serum level.
Tizanidine Tizanidine The risk or severity of adverse effects can be increased when Tizanidine is combined with Promethazine.
Zolmitriptan Zolmitriptan The risk or severity of adverse effects can be increased when Zolmitriptan is combined with Promethazine.
Ampicillin Injection Ampicillin Injection Ampicillin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Doxycycline Injection Doxycycline Injection Doxycycline may decrease the excretion rate of Promethazine which could result in a higher serum level.
Famotidine Injection Famotidine Injection The risk or severity of QTc prolongation can be increased when Famotidine is combined with Promethazine.
Fluconazole Injection Fluconazole Injection The risk or severity of QTc prolongation can be increased when Fluconazole is combined with Promethazine.
Foscarnet Injection Foscarnet Injection Foscarnet may decrease the excretion rate of Promethazine which could result in a higher serum level.
Hydromorphone Injection Hydromorphone Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Hydromorphone.
Levofloxacin Injection Levofloxacin Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Levofloxacin.
Meperidine Injection Meperidine Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Meperidine.
Metoclopramide Injection Metoclopramide Injection The risk or severity of adverse effects can be increased when Metoclopramide is combined with Promethazine.
Metronidazole Injection Metronidazole Injection The risk or severity of QTc prolongation can be increased when Metronidazole is combined with Promethazine.
Morphine Injection Morphine Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Morphine.
Pamidronate Injection Pamidronate Injection Pamidronic acid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Vancomycin Injection Vancomycin Injection Promethazine may decrease the excretion rate of Vancomycin which could result in a higher serum level.
Zidovudine Injection Zidovudine Injection The metabolism of Zidovudine can be decreased when combined with Promethazine.
Altretamine Altretamine Amphetamine may decrease the sedative and stimulatory activities of Promethazine.
Cefuroxime Cefuroxime Promethazine can cause a decrease in the absorption of Cefuroxime resulting in a reduced serum concentration and potentially a decrease in efficacy.
Cyclosporine Cyclosporine The metabolism of Cyclosporine can be decreased when combined with Promethazine.
Ondansetron Ondansetron The metabolism of Ondansetron can be decreased when combined with Promethazine.
Granisetron Granisetron The risk or severity of adverse effects can be increased when Granisetron is combined with Promethazine.
Torsemide Torsemide The metabolism of Torasemide can be decreased when combined with Promethazine.
Olanzapine Olanzapine Olanzapine may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Alosetron Alosetron The metabolism of Alosetron can be decreased when combined with Promethazine.
Dofetilide Dofetilide The risk or severity of QTc prolongation can be increased when Promethazine is combined with Dofetilide.
Entacapone Entacapone The risk or severity of adverse effects can be increased when Entacapone is combined with Promethazine.
Hydroxychloroquine Hydroxychloroquine The risk or severity of QTc prolongation can be increased when Hydroxychloroquine is combined with Promethazine.
Meloxicam Meloxicam Meloxicam may decrease the excretion rate of Promethazine which could result in a higher serum level.
Oxcarbazepine Oxcarbazepine The risk or severity of adverse effects can be increased when Oxcarbazepine is combined with Promethazine.
Pantoprazole Pantoprazole Pantoprazole may decrease the excretion rate of Promethazine which could result in a higher serum level.
Risedronate Risedronate Promethazine can cause an increase in the absorption of Risedronic acid resulting in an increased serum concentration and potentially a worsening of adverse effects.
Temozolomide Temozolomide Temozolomide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Zaleplon Zaleplon The risk or severity of adverse effects can be increased when Zaleplon is combined with Promethazine.
Anakinra Anakinra The metabolism of Promethazine can be increased when combined with Anakinra.
Desloratadine Desloratadine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Desloratadine.
Linezolid Linezolid The risk or severity of serotonin syndrome can be increased when Linezolid is combined with Promethazine.
Rivastigmine Rivastigmine The therapeutic efficacy of Promethazine can be decreased when used in combination with Rivastigmine.
Trimipramine Trimipramine The serum concentration of Trimipramine can be increased when it is combined with Promethazine.
Etanercept Injection Etanercept Injection The metabolism of Promethazine can be increased when combined with Etanercept.
Glycopyrrolate Glycopyrrolate The risk or severity of adverse effects can be increased when Promethazine is combined with Glycopyrronium.
Modafinil Modafinil The metabolism of Promethazine can be decreased when combined with Modafinil.
Perindopril Perindopril Perindopril may decrease the excretion rate of Promethazine which could result in a higher serum level.
Tenofovir Tenofovir Tenofovir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Choline Magnesium Trisalicylate Choline Magnesium Trisalicylate Choline magnesium trisalicylate may decrease the excretion rate of Promethazine which could result in a higher serum level.
Epinephrine Injection Epinephrine Injection Promethazine may decrease the vasoconstricting activities of Epinephrine.
Eplerenone Eplerenone Eplerenone may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Escitalopram Escitalopram The risk or severity of serotonin syndrome can be increased when Promethazine is combined with Escitalopram.
Zonisamide Zonisamide The risk or severity of adverse effects can be increased when Zonisamide is combined with Promethazine.
Adalimumab Injection Adalimumab Injection The metabolism of Promethazine can be increased when combined with Adalimumab.
Aripiprazole Aripiprazole The metabolism of Aripiprazole can be decreased when combined with Promethazine.
Atomoxetine Atomoxetine The metabolism of Atomoxetine can be decreased when combined with Promethazine.
Dexmethylphenidate Dexmethylphenidate The therapeutic efficacy of Dexmethylphenidate can be decreased when used in combination with Promethazine.
Atazanavir Atazanavir Promethazine can cause a decrease in the absorption of Atazanavir resulting in a reduced serum concentration and potentially a decrease in efficacy.
Almotriptan Almotriptan Almotriptan may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Eletriptan Eletriptan The metabolism of Eletriptan can be decreased when combined with Promethazine.
Mefloquine Mefloquine The risk or severity of QTc prolongation can be increased when Mefloquine is combined with Promethazine.
Polyethylene Glycol 3350 Polyethylene Glycol 3350 The therapeutic efficacy of Polyethylene glycol can be decreased when used in combination with Promethazine.
Rosuvastatin Rosuvastatin The metabolism of Rosuvastatin can be decreased when combined with Promethazine.
Vardenafil Vardenafil The risk or severity of QTc prolongation can be increased when Vardenafil is combined with Promethazine.
Alfuzosin Alfuzosin The risk or severity of QTc prolongation can be increased when Alfuzosin is combined with Promethazine.
Emtricitabine Emtricitabine Emtricitabine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Memantine Memantine The metabolism of Promethazine can be decreased when combined with Memantine.
Tegaserod Tegaserod The metabolism of Tegaserod can be decreased when combined with Promethazine.
Tadalafil Tadalafil Tadalafil may decrease the excretion rate of Promethazine which could result in a higher serum level.
Fosamprenavir Fosamprenavir Promethazine can cause a decrease in the absorption of Fosamprenavir resulting in a reduced serum concentration and potentially a decrease in efficacy.
Frovatriptan Frovatriptan The risk or severity of adverse effects can be increased when Frovatriptan is combined with Promethazine.
Gemifloxacin Gemifloxacin The risk or severity of QTc prolongation can be increased when Promethazine is combined with Gemifloxacin.
Progesterone Progesterone The metabolism of Progesterone can be decreased when combined with Promethazine.
Apomorphine Injection Apomorphine Injection The risk or severity of adverse effects can be increased when Apomorphine is combined with Promethazine.
Infliximab Injection Infliximab Injection The metabolism of Promethazine can be increased when combined with Infliximab.
Protriptyline Protriptyline The serum concentration of Protriptyline can be increased when it is combined with Promethazine.
Duloxetine Duloxetine The metabolism of Duloxetine can be decreased when combined with Promethazine.
Tinidazole Tinidazole Tinidazole may decrease the excretion rate of Promethazine which could result in a higher serum level.
Trospium Trospium Promethazine may increase the central nervous system depressant (CNS depressant) activities of Trospium.
Bosentan Bosentan The metabolism of Bosentan can be decreased when combined with Promethazine.
Cefditoren Cefditoren Cefdinir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cinacalcet Cinacalcet The metabolism of Promethazine can be decreased when combined with Cinacalcet.
Cyanocobalamin Injection Cyanocobalamin Injection Hydroxocobalamin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Erlotinib Erlotinib Promethazine can cause a decrease in the absorption of Erlotinib resulting in a reduced serum concentration and potentially a decrease in efficacy.
Eszopiclone Eszopiclone The risk or severity of CNS depression can be increased when Promethazine is combined with Eszopiclone.
Ganciclovir Ganciclovir Ganciclovir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Ribavirin Ribavirin Ribavirin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Solifenacin Solifenacin Promethazine may increase the central nervous system depressant (CNS depressant) activities of Solifenacin.
Valganciclovir Valganciclovir Promethazine may decrease the excretion rate of Valganciclovir which could result in a higher serum level.
Voriconazole Voriconazole The metabolism of Promethazine can be decreased when combined with Voriconazole.
Adefovir Adefovir Adefovir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Dextroamphetamine Dextroamphetamine Amphetamine may decrease the sedative and stimulatory activities of Promethazine.
Peginterferon Alfa-2b (PEG-Intron) Peginterferon Alfa-2b (PEG-Intron) The metabolism of Promethazine can be decreased when combined with Peginterferon alfa-2b.
Pramlintide Injection Pramlintide Injection The risk or severity of reduced gastrointestinal motility can be increased when Pramlintide is combined with Promethazine.
Sodium Oxybate Sodium Oxybate Sodium oxybate may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Ibandronate Ibandronate The risk or severity of QTc prolongation can be increased when Ibandronate is combined with Promethazine.
Isocarboxazid Isocarboxazid The risk or severity of extrapyramidal symptoms can be increased when Promethazine is combined with Isocarboxazid.
Ramelteon Ramelteon The risk or severity of adverse effects can be increased when Ramelteon is combined with Promethazine.
Darifenacin Darifenacin The metabolism of Promethazine can be decreased when combined with Darifenacin.
Fentanyl Fentanyl The risk or severity of adverse effects can be increased when Promethazine is combined with Fentanyl.
Pregabalin Pregabalin The therapeutic efficacy of Promethazine can be increased when used in combination with Pregabalin.
Tipranavir Tipranavir The metabolism of Promethazine can be decreased when combined with Tipranavir.
Felbamate Felbamate The risk or severity of adverse effects can be increased when Felbamate is combined with Promethazine.
Ranolazine Ranolazine The serum concentration of Ranolazine can be increased when it is combined with Promethazine.
Abatacept Injection Abatacept Injection The metabolism of Promethazine can be increased when combined with Abatacept.
Rasagiline Rasagiline The risk or severity of extrapyramidal symptoms can be increased when Promethazine is combined with Rasagiline.
Imatinib Imatinib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Imatinib.
Sitagliptin Sitagliptin Promethazine may decrease the excretion rate of Sitagliptin which could result in a higher serum level.
Varenicline Varenicline Promethazine may decrease the excretion rate of Varenicline which could result in a higher serum level.
Gefitinib Gefitinib Promethazine can cause a decrease in the absorption of Gefitinib resulting in a reduced serum concentration and potentially a decrease in efficacy.
Albuterol Albuterol The risk or severity of QTc prolongation can be increased when Salbutamol is combined with Promethazine.
Paliperidone Paliperidone The risk or severity of QTc prolongation can be increased when Promethazine is combined with Paliperidone.
Bortezomib Bortezomib The metabolism of Bortezomib can be decreased when combined with Promethazine.
Clofarabine Injection Clofarabine Injection Clofarabine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Lubiprostone Lubiprostone Promethazine may decrease the excretion rate of Lubiprostone which could result in a higher serum level.
Oxaliplatin Injection Oxaliplatin Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Oxaliplatin.
Posaconazole Posaconazole The risk or severity of QTc prolongation can be increased when Promethazine is combined with Posaconazole.
Primaquine Primaquine The metabolism of Promethazine can be decreased when combined with Primaquine.
Bismuth Subsalicylate Bismuth Subsalicylate Promethazine may increase the neurotoxic activities of Bismuth subsalicylate.
Pemetrexed Injection Pemetrexed Injection Promethazine may decrease the excretion rate of Pemetrexed which could result in a higher serum level.
Dimenhydrinate Dimenhydrinate The risk or severity of adverse effects can be increased when Dimenhydrinate is combined with Promethazine.
Lisdexamfetamine Lisdexamfetamine Lisdexamfetamine may decrease the sedative and stimulatory activities of Promethazine.
Nabilone Nabilone Nabilone may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Vorinostat Vorinostat The risk or severity of QTc prolongation can be increased when Promethazine is combined with Vorinostat.
Sorafenib Sorafenib The metabolism of Promethazine can be decreased when combined with Sorafenib.
Sunitinib Sunitinib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Sunitinib.
Dronabinol Dronabinol Dronabinol may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Lapatinib Lapatinib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Lapatinib.
Levocetirizine Levocetirizine The risk or severity of adverse effects can be increased when Promethazine is combined with Levocetirizine.
Pegaptanib Injection Pegaptanib Injection Promethazine may decrease the excretion rate of Pegaptanib which could result in a higher serum level.
Dasatinib Dasatinib Promethazine can cause a decrease in the absorption of Dasatinib resulting in a reduced serum concentration and potentially a decrease in efficacy.
Mexiletine Mexiletine The metabolism of Promethazine can be decreased when combined with Mexiletine.
Armodafinil Armodafinil The metabolism of Promethazine can be increased when combined with Armodafinil.
Azacitidine Injection Azacitidine Injection Azacitidine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Paclitaxel (with polyoxyethylated castor oil) Injection Paclitaxel (with polyoxyethylated castor oil) Injection The therapeutic efficacy of Castor oil can be decreased when used in combination with Promethazine.
Temsirolimus Temsirolimus The metabolism of Promethazine can be decreased when combined with Temsirolimus.
Lenalidomide Lenalidomide Lenalidomide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Nilotinib Nilotinib Promethazine can cause a decrease in the absorption of Nilotinib resulting in a reduced serum concentration and potentially a decrease in efficacy.
Toremifene Toremifene The risk or severity of QTc prolongation can be increased when Promethazine is combined with Toremifene.
Bexarotene Bexarotene The metabolism of Bexarotene can be decreased when combined with Promethazine.
Budesonide Budesonide Promethazine can cause a decrease in the absorption of Budesonide resulting in a reduced serum concentration and potentially a decrease in efficacy.
Desmopressin Desmopressin Desmopressin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Betaine Betaine The therapeutic efficacy of Promethazine can be decreased when used in combination with Glycine betaine.
OnabotulinumtoxinA Injection OnabotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Botulinum toxin type A.
RimabotulinumtoxinB Injection RimabotulinumtoxinB Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Botulinum Toxin Type B.
Doripenem Injection Doripenem Injection Promethazine may decrease the excretion rate of Doripenem which could result in a higher serum level.
Etravirine Etravirine The metabolism of Etravirine can be decreased when combined with Promethazine.
Arsenic Trioxide Injection Arsenic Trioxide Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Arsenic trioxide.
Desvenlafaxine Desvenlafaxine The risk or severity of adverse effects can be increased when Promethazine is combined with Desvenlafaxine.
Cevimeline Cevimeline The metabolism of Cevimeline can be decreased when combined with Promethazine.
Nebivolol Nebivolol The serum concentration of Nebivolol can be increased when it is combined with Promethazine.
Tretinoin Tretinoin The metabolism of Promethazine can be decreased when combined with Tretinoin.
Flecainide Flecainide The metabolism of Flecainide can be decreased when combined with Promethazine.
Certolizumab Injection Certolizumab Injection The metabolism of Promethazine can be increased when combined with Certolizumab pegol.
Irinotecan Injection Irinotecan Injection The metabolism of Promethazine can be decreased when combined with Irinotecan.
Daptomycin Injection Daptomycin Injection Daptomycin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Methylnaltrexone Injection Methylnaltrexone Injection Promethazine may decrease the excretion rate of Methylnaltrexone which could result in a higher serum level.
Rufinamide Rufinamide The risk or severity of adverse effects can be increased when Rufinamide is combined with Promethazine.
Midazolam Midazolam Midazolam may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Naltrexone Injection Naltrexone Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Naltrexone.
Dexrazoxane Injection Dexrazoxane Injection Dexrazoxane may decrease the excretion rate of Promethazine which could result in a higher serum level.
Milnacipran Milnacipran The risk or severity of adverse effects can be increased when Promethazine is combined with Milnacipran.
Plerixafor Injection Plerixafor Injection Promethazine may decrease the excretion rate of Plerixafor which could result in a higher serum level.
Sodium Phosphate Sodium Phosphate The therapeutic efficacy of Sodium phosphate, monobasic can be decreased when used in combination with Promethazine.
Fesoterodine Fesoterodine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Fesoterodine.
Degarelix Injection Degarelix Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Degarelix.
Betaxolol Betaxolol The serum concentration of Betaxolol can be increased when it is combined with Promethazine.
Iloperidone Iloperidone The risk or severity of QTc prolongation can be increased when Promethazine is combined with Iloperidone.
Prasugrel Prasugrel The metabolism of Prasugrel can be decreased when combined with Promethazine.
Lacosamide Lacosamide The risk or severity of adverse effects can be increased when Promethazine is combined with Lacosamide.
Everolimus Everolimus The metabolism of Promethazine can be decreased when combined with Everolimus.
Tolvaptan (low blood sodium) Tolvaptan (low blood sodium) Tolvaptan may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Dronedarone Dronedarone The metabolism of Dronedarone can be decreased when combined with Promethazine.
AbobotulinumtoxinA Injection AbobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Botulinum toxin type A.
Pralatrexate Injection Pralatrexate Injection Promethazine may decrease the excretion rate of Pralatrexate which could result in a higher serum level.
Palonosetron Injection Palonosetron Injection Palonosetron may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Saxagliptin Saxagliptin Promethazine may decrease the excretion rate of Saxagliptin which could result in a higher serum level.
Telavancin Injection Telavancin Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Telavancin.
Romidepsin Injection Romidepsin Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Romidepsin.
Tapentadol Tapentadol Tapentadol may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Topotecan Topotecan Topotecan may decrease the excretion rate of Promethazine which could result in a higher serum level.
Golimumab Injection Golimumab Injection The metabolism of Promethazine can be increased when combined with Golimumab.
Pazopanib Pazopanib The therapeutic efficacy of Pazopanib can be decreased when used in combination with Promethazine.
Asenapine Asenapine The risk or severity of QTc prolongation can be increased when Promethazine is combined with Asenapine.
Vigabatrin Vigabatrin The risk or severity of adverse effects can be increased when Promethazine is combined with Vigabatrin.
Pitavastatin Pitavastatin The metabolism of Pitavastatin can be decreased when combined with Promethazine.
Oxymorphone Oxymorphone The risk or severity of adverse effects can be increased when Promethazine is combined with Oxymorphone.
Tocilizumab Injection Tocilizumab Injection The metabolism of Promethazine can be increased when combined with Tocilizumab.
Dalfampridine Dalfampridine The risk or severity of seizure can be increased when Promethazine is combined with Dalfampridine.
Eribulin Injection Eribulin Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Eribulin.
IncobotulinumtoxinA Injection IncobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Botulinum toxin type A.
Ceftaroline Injection Ceftaroline Injection Ceftaroline fosamil may decrease the excretion rate of Promethazine which could result in a higher serum level.
Lurasidone Lurasidone The risk or severity of adverse effects can be increased when Promethazine is combined with Lurasidone.
Acetaminophen Injection Acetaminophen Injection The metabolism of Acetaminophen can be decreased when combined with Promethazine.
Vilazodone Vilazodone The metabolism of Vilazodone can be decreased when combined with Promethazine.
Ipilimumab Injection Ipilimumab Injection Promethazine may decrease the excretion rate of Ipilimumab which could result in a higher serum level.
Denileukin Diftitox Injection Denileukin Diftitox Injection Aldesleukin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Terbutaline Injection Terbutaline Injection The risk or severity of QTc prolongation can be increased when Terbutaline is combined with Promethazine.
Roflumilast Roflumilast Promethazine may decrease the excretion rate of Roflumilast which could result in a higher serum level.
Rilpivirine Rilpivirine Promethazine can cause a decrease in the absorption of Rilpivirine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Cyclophosphamide Injection Cyclophosphamide Injection The metabolism of Promethazine can be decreased when combined with Cyclophosphamide.
Abiraterone Abiraterone The metabolism of Promethazine can be decreased when combined with Abiraterone.
Triptorelin Injection Triptorelin Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Triptorelin.
Rivaroxaban Rivaroxaban Promethazine may decrease the excretion rate of Rivaroxaban which could result in a higher serum level.
Ruxolitinib Ruxolitinib Promethazine may decrease the excretion rate of Ruxolitinib which could result in a higher serum level.
Vandetanib Vandetanib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Vandetanib.
Clobazam Clobazam The metabolism of Promethazine can be decreased when combined with Clobazam.
Vemurafenib Vemurafenib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Vemurafenib.
Vismodegib Vismodegib The metabolism of Vismodegib can be decreased when combined with Promethazine.
Deferiprone Deferiprone Promethazine may decrease the excretion rate of Deferiprone which could result in a higher serum level.
Crizotinib Crizotinib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Crizotinib.
Cabergoline Cabergoline Cabergoline may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Naloxone Injection Naloxone Injection Promethazine may decrease the excretion rate of Naloxone which could result in a higher serum level.
Fondaparinux Injection Fondaparinux Injection Fondaparinux may decrease the excretion rate of Promethazine which could result in a higher serum level.
Ezogabine Ezogabine The risk or severity of adverse effects can be increased when Tiagabine is combined with Promethazine.
Enzalutamide Enzalutamide The metabolism of Enzalutamide can be decreased when combined with Promethazine.
Mirabegron Mirabegron The risk or severity of urinary retention can be increased when Promethazine is combined with Mirabegron.
Regorafenib Regorafenib The metabolism of Promethazine can be decreased when combined with Regorafenib.
Bosutinib Bosutinib Promethazine can cause a decrease in the absorption of Bosutinib resulting in a reduced serum concentration and potentially a decrease in efficacy.
Linaclotide Linaclotide The therapeutic efficacy of Linaclotide can be decreased when used in combination with Promethazine.
Cabozantinib (thyroid cancer) Cabozantinib (thyroid cancer) The metabolism of Cabozantinib can be decreased when combined with Promethazine.
Teduglutide Injection Teduglutide Injection Promethazine may decrease the excretion rate of Teduglutide which could result in a higher serum level.
Bedaquiline Bedaquiline The risk or severity of QTc prolongation can be increased when Promethazine is combined with Bedaquiline.
Alogliptin Alogliptin The metabolism of Alogliptin can be decreased when combined with Promethazine.
Ponatinib Ponatinib The metabolism of Ponatinib can be decreased when combined with Promethazine.
Pomalidomide Pomalidomide Pomalidomide may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Apixaban Apixaban The metabolism of Apixaban can be decreased when combined with Promethazine.
Canagliflozin Canagliflozin Promethazine may increase the excretion rate of Canagliflozin which could result in a lower serum level and potentially a reduction in efficacy.
Methazolamide Methazolamide Methazolamide may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Dabrafenib Dabrafenib Promethazine can cause a decrease in the absorption of Dabrafenib resulting in a reduced serum concentration and potentially a decrease in efficacy.
Ospemifene Ospemifene The metabolism of Ospemifene can be decreased when combined with Promethazine.
Trametinib Trametinib Promethazine may decrease the excretion rate of Trametinib which could result in a higher serum level.
Levomilnacipran Levomilnacipran The risk or severity of adverse effects can be increased when Promethazine is combined with Levomilnacipran.
Ertapenem Injection Ertapenem Injection Ertapenem may decrease the excretion rate of Promethazine which could result in a higher serum level.
Vortioxetine Vortioxetine The metabolism of Vortioxetine can be decreased when combined with Promethazine.
Perampanel Perampanel Perampanel may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Ibrutinib Ibrutinib The metabolism of Ibrutinib can be decreased when combined with Promethazine.
Ketorolac Injection Ketorolac Injection Ketorolac may decrease the excretion rate of Promethazine which could result in a higher serum level.
Sofosbuvir Sofosbuvir Promethazine may decrease the excretion rate of Sofosbuvir which could result in a higher serum level.
Dapagliflozin Dapagliflozin The metabolism of Dapagliflozin can be decreased when combined with Promethazine.
Iron Sucrose Injection Iron Sucrose Injection Promethazine can cause a decrease in the absorption of Iron sucrose resulting in a reduced serum concentration and potentially a decrease in efficacy.
Apremilast Apremilast The metabolism of Promethazine can be increased when combined with Apremilast.
Droxidopa Droxidopa The therapeutic efficacy of Droxidopa can be increased when used in combination with Promethazine.
Ceritinib Ceritinib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Ceritinib.
Siltuximab Injection Siltuximab Injection The metabolism of Promethazine can be increased when combined with Siltuximab.
Eslicarbazepine Eslicarbazepine The risk or severity of adverse effects can be increased when Promethazine is combined with Eslicarbazepine.
Testosterone Injection Testosterone Injection The metabolism of Testosterone can be decreased when combined with Promethazine.
Oritavancin Injection Oritavancin Injection The metabolism of Promethazine can be decreased when combined with Oritavancin.
Hydrocodone Hydrocodone Hydrocodone may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Suvorexant Suvorexant Promethazine may increase the central nervous system depressant (CNS depressant) activities of Suvorexant.
Edoxaban Edoxaban Promethazine may decrease the excretion rate of Edoxaban which could result in a higher serum level.
Olaparib Olaparib The metabolism of Promethazine can be increased when combined with Olaparib.
Methamphetamine Methamphetamine Metamfetamine may decrease the sedative and stimulatory activities of Promethazine.
Tasimelteon Tasimelteon The risk or severity of adverse effects can be increased when Promethazine is combined with Tasimelteon.
Secukinumab Injection Secukinumab Injection The metabolism of Promethazine can be increased when combined with Secukinumab.
Risperidone Injection Risperidone Injection Risperidone may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Lenvatinib Lenvatinib The metabolism of Promethazine can be decreased when combined with Lenvatinib.
Naloxegol Naloxegol The metabolism of Promethazine can be decreased when combined with Naloxegol.
Panobinostat Panobinostat The metabolism of Promethazine can be decreased when combined with Panobinostat.
Haloperidol Injection Haloperidol Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Haloperidol.
Ivabradine Ivabradine The risk or severity of QTc prolongation can be increased when Promethazine is combined with Ivabradine.
Amiloride Amiloride Amiloride may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Isavuconazonium Injection Isavuconazonium Injection Promethazine can cause a decrease in the absorption of Isavuconazonium resulting in a reduced serum concentration and potentially a decrease in efficacy.
Macitentan Macitentan Promethazine may decrease the excretion rate of Macitentan which could result in a higher serum level.
Flibanserin Flibanserin The risk or severity of adverse effects can be increased when Promethazine is combined with Flibanserin.
Rolapitant Rolapitant The metabolism of Promethazine can be decreased when combined with Rolapitant.
Brexpiprazole Brexpiprazole The risk or severity of adverse effects can be increased when Promethazine is combined with Brexpiprazole.
Ziprasidone Injection Ziprasidone Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Ziprasidone.
Cariprazine Cariprazine The risk or severity of adverse effects can be increased when Promethazine is combined with Cariprazine.
Penicillin G Procaine Injection Penicillin G Procaine Injection Promethazine may decrease the excretion rate of Procaine benzylpenicillin which could result in a higher serum level.
Eluxadoline Eluxadoline The risk or severity of constipation can be increased when Promethazine is combined with Eluxadoline.
Trabectedin Injection Trabectedin Injection The metabolism of Trabectedin can be decreased when combined with Promethazine.
Ixazomib Ixazomib Promethazine may decrease the excretion rate of Ixazomib which could result in a higher serum level.
Rifapentine Rifapentine The metabolism of Promethazine can be increased when combined with Rifapentine.
Lesinurad Lesinurad The metabolism of Lesinurad can be decreased when combined with Promethazine.
Amphotericin B Liposomal Injection Amphotericin B Liposomal Injection Amphotericin B may decrease the excretion rate of Promethazine which could result in a higher serum level.
Dexamethasone Injection Dexamethasone Injection The metabolism of Promethazine can be increased when combined with Dexamethasone.
Brivaracetam Injection Brivaracetam Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Brivaracetam.
Cobicistat Cobicistat The metabolism of Promethazine can be decreased when combined with Cobicistat.
Midodrine Midodrine The risk or severity of Tachycardia can be increased when Midodrine is combined with Promethazine.
Pimavanserin Pimavanserin The risk or severity of adverse effects can be increased when Promethazine is combined with Pimavanserin.
Diphenhydramine Injection Diphenhydramine Injection The metabolism of Diphenhydramine can be decreased when combined with Promethazine.
Furosemide Injection Furosemide Injection Furosemide may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Rucaparib Rucaparib The metabolism of Rucaparib can be decreased when combined with Promethazine.
Lixisenatide Injection Lixisenatide Injection Promethazine may decrease the excretion rate of Lixisenatide which could result in a higher serum level.
Ribociclib Ribociclib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Ribociclib.
Doxepin (Insomnia) Doxepin (Insomnia) The serum concentration of Doxepin can be increased when it is combined with Promethazine.
Plecanatide Plecanatide The therapeutic efficacy of Plecanatide can be decreased when used in combination with Promethazine.
Deutetrabenazine Deutetrabenazine The risk or severity of adverse effects can be increased when Promethazine is combined with Deutetrabenazine.
Valbenazine Valbenazine The metabolism of Valbenazine can be decreased when combined with Promethazine.
Safinamide Safinamide The risk or severity of extrapyramidal symptoms can be increased when Promethazine is combined with Safinamide.
Naldemedine Naldemedine Promethazine may decrease the excretion rate of Naldemedine which could result in a higher serum level.
Midostaurin Midostaurin The metabolism of Promethazine can be decreased when combined with Midostaurin.
Enasidenib Enasidenib The metabolism of Enasidenib can be decreased when combined with Promethazine.
Benznidazole Benznidazole Promethazine may decrease the excretion rate of Benznidazole which could result in a higher serum level.
Delafloxacin Delafloxacin The risk or severity of QTc prolongation can be increased when Promethazine is combined with Delafloxacin.
Letermovir Letermovir The metabolism of Letermovir can be decreased when combined with Promethazine.
Tetrabenazine Tetrabenazine The risk or severity of adverse effects can be increased when Promethazine is combined with Tetrabenazine.
Ertugliflozin Ertugliflozin Ertugliflozin may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Buprenorphine Injection Buprenorphine Injection Promethazine may increase the central nervous system depressant (CNS depressant) activities of Buprenorphine.
Apalutamide Apalutamide Promethazine may decrease the excretion rate of Apalutamide which could result in a higher serum level.
Baricitinib Baricitinib Promethazine may decrease the excretion rate of Baricitinib which could result in a higher serum level.
Lofexidine Lofexidine The therapeutic efficacy of Promethazine can be increased when used in combination with Lofexidine.
Plazomicin Injection Plazomicin Injection Promethazine may decrease the excretion rate of Plazomicin which could result in a higher serum level.
Eliglustat Eliglustat The risk or severity of QTc prolongation can be increased when Promethazine is combined with Eliglustat.
Encorafenib Encorafenib The metabolism of Encorafenib can be decreased when combined with Promethazine.
Ivosidenib Ivosidenib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Ivosidenib.
Elagolix Elagolix The metabolism of Elagolix can be decreased when combined with Promethazine.
Tafenoquine Tafenoquine The risk or severity of QTc prolongation can be increased when Tafenoquine is combined with Promethazine.
Cannabidiol Cannabidiol The risk or severity of adverse effects can be increased when Cannabidiol is combined with Promethazine.
Dacomitinib Dacomitinib The metabolism of Promethazine can be decreased when combined with Dacomitinib.
Stiripentol Stiripentol The risk or severity of adverse effects can be increased when Promethazine is combined with Stiripentol.
Gilteritinib Gilteritinib The therapeutic efficacy of Promethazine can be decreased when used in combination with Gilteritinib.
Glasdegib Glasdegib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Glasdegib.
Lorlatinib Lorlatinib The metabolism of Promethazine can be increased when combined with Lorlatinib.
Paclitaxel (with albumin) Injection Paclitaxel (with albumin) Injection Promethazine may increase the neurotoxic activities of Paclitaxel.
Rifamycin Rifamycin The metabolism of Promethazine can be decreased when combined with Rifamycin.
Prucalopride Prucalopride Promethazine may decrease the excretion rate of Prucalopride which could result in a higher serum level.
Magnesium Citrate Magnesium Citrate The therapeutic efficacy of Magnesium citrate can be decreased when used in combination with Promethazine.
Emapalumab-lzsg Injection Emapalumab-lzsg Injection The metabolism of Promethazine can be increased when combined with Emapalumab.
Siponimod Siponimod The metabolism of Siponimod can be decreased when combined with Promethazine.
Acyclovir Ophthalmic Acyclovir Ophthalmic Acyclovir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Erdafitinib Erdafitinib The metabolism of Erdafitinib can be decreased when combined with Promethazine.
Alpelisib Alpelisib The metabolism of Promethazine can be increased when combined with Alpelisib.
Brexanolone Injection Brexanolone Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Brexanolone.
Solriamfetol Solriamfetol The risk or severity of Tachycardia can be increased when Solriamfetol is combined with Promethazine.
Triclabendazole Triclabendazole The metabolism of Promethazine can be decreased when combined with Triclabendazole.
Entrectinib Entrectinib The risk or severity of QTc prolongation can be increased when Promethazine is combined with Entrectinib.
Istradefylline Istradefylline The metabolism of Istradefylline can be decreased when combined with Promethazine.
Pitolisant Pitolisant The therapeutic efficacy of Pitolisant can be decreased when used in combination with Promethazine.
Fedratinib Fedratinib The metabolism of Promethazine can be decreased when combined with Fedratinib.
Lefamulin Lefamulin Promethazine may increase the QTc-prolonging activities of Lefamulin.
Phenytoin Injection Phenytoin Injection The serum concentration of Phenytoin can be increased when it is combined with Promethazine.
Fosphenytoin Injection Fosphenytoin Injection The serum concentration of Fosphenytoin can be increased when it is combined with Promethazine.
Zanubrutinib Zanubrutinib The metabolism of Zanubrutinib can be decreased when combined with Promethazine.
Voxelotor Voxelotor The metabolism of Voxelotor can be decreased when combined with Promethazine.
Avapritinib Avapritinib The metabolism of Avapritinib can be decreased when combined with Promethazine.
Lumateperone Lumateperone The risk or severity of adverse effects can be increased when Promethazine is combined with Lumateperone.
Lasmiditan Lasmiditan The risk or severity of serotonin syndrome can be increased when Promethazine is combined with Lasmiditan.
Cenobamate Cenobamate The serum concentration of Cenobamate can be decreased when it is combined with Promethazine.
Selumetinib Selumetinib The metabolism of Selumetinib can be decreased when combined with Promethazine.
Selpercatinib Selpercatinib The serum concentration of Selpercatinib can be decreased when it is combined with Promethazine.
Lemborexant Lemborexant The serum concentration of Promethazine can be decreased when it is combined with Lemborexant.
Daratumumab and Hyaluronidase-fihj Injection Daratumumab and Hyaluronidase-fihj Injection The therapeutic efficacy of Hyaluronidase can be decreased when used in combination with Promethazine.
Fenfluramine Fenfluramine The risk or severity of serotonin syndrome can be increased when Fenfluramine is combined with Promethazine.
Fostemsavir Fostemsavir The risk or severity of QTc prolongation can be increased when Promethazine is combined with Fostemsavir.
Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf Injection Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf Injection The therapeutic efficacy of Hyaluronidase can be decreased when used in combination with Promethazine.
Octreotide Octreotide The risk or severity of QTc prolongation can be increased when Octreotide is combined with Promethazine.
Naxitamab-gqgk Injection Naxitamab-gqgk Injection Promethazine may increase the neurotoxic activities of Naxitamab.
Relugolix Relugolix The risk or severity of QTc prolongation can be increased when Promethazine is combined with Relugolix.
Progestin-Only (drospirenone) Oral Contraceptives Progestin-Only (drospirenone) Oral Contraceptives Drospirenone may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Viloxazine Viloxazine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Viloxazine.
Tobramycin Injection Tobramycin Injection Tobramycin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Theophylline Theophylline The metabolism of Theophylline can be decreased when combined with Promethazine.
Fenoprofen Fenoprofen Fenoprofen may decrease the excretion rate of Promethazine which could result in a higher serum level.
Indomethacin Indomethacin The metabolism of Indomethacin can be decreased when combined with Promethazine.
Mefenamic Acid Mefenamic Acid Mefenamic acid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Naproxen Naproxen Naproxen may decrease the excretion rate of Promethazine which could result in a higher serum level.
Tolmetin Tolmetin Tolmetin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Sulindac Sulindac Sulindac may decrease the excretion rate of Promethazine which could result in a higher serum level.
Trazodone Trazodone The risk or severity of QTc prolongation can be increased when Trazodone is combined with Promethazine.
Isotretinoin Isotretinoin Isotretinoin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Sucralfate Sucralfate Sucralfate may decrease the excretion rate of Promethazine which could result in a higher serum level.
Sodium Bicarbonate Sodium Bicarbonate Sodium bicarbonate can cause a decrease in the absorption of Promethazine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Hydroxyurea Hydroxyurea The metabolism of Promethazine can be decreased when combined with Hydroxyurea.
Floxuridine Floxuridine Floxuridine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Phenobarbital Phenobarbital The metabolism of Phenobarbital can be decreased when combined with Promethazine.
Metaxalone Metaxalone Metaxalone may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Methotrexate Injection Methotrexate Injection Methotrexate may decrease the excretion rate of Promethazine which could result in a higher serum level.
Levorphanol Levorphanol The risk or severity of adverse effects can be increased when Promethazine is combined with Levorphanol.
Primidone Primidone The metabolism of Primidone can be decreased when combined with Promethazine.
Methsuximide Methsuximide The risk or severity of adverse effects can be increased when Promethazine is combined with Methsuximide.
Diethylpropion Diethylpropion Diethylpropion may decrease the sedative and stimulatory activities of Promethazine.
Chlorpromazine Chlorpromazine The metabolism of Promethazine can be decreased when combined with Chlorpromazine.
Diazepam Diazepam The metabolism of Diazepam can be decreased when combined with Promethazine.
Oxazepam Oxazepam The risk or severity of adverse effects can be increased when Oxazepam is combined with Promethazine.
Flurazepam Flurazepam The risk or severity of adverse effects can be increased when Flurazepam is combined with Promethazine.
Clorazepate Clorazepate The risk or severity of adverse effects can be increased when Clorazepic acid is combined with Promethazine.
Lorazepam Lorazepam The risk or severity of adverse effects can be increased when Lorazepam is combined with Promethazine.
Carmustine Carmustine Carmustine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Amantadine Amantadine The risk or severity of QTc prolongation can be increased when Amantadine is combined with Promethazine.
Meprobamate Meprobamate The risk or severity of adverse effects can be increased when Meprobamate is combined with Promethazine.
Chlordiazepoxide Chlordiazepoxide The risk or severity of adverse effects can be increased when Chlordiazepoxide is combined with Promethazine.
Bromocriptine Bromocriptine The risk or severity of adverse effects can be increased when Promethazine is combined with Bromocriptine.
Metaproterenol Metaproterenol The risk or severity of Tachycardia can be increased when Orciprenaline is combined with Promethazine.
Tranylcypromine Tranylcypromine The metabolism of Promethazine can be decreased when combined with Tranylcypromine.
Phenelzine Phenelzine The risk or severity of extrapyramidal symptoms can be increased when Phenelzine is combined with Promethazine.
Procarbazine Procarbazine The risk or severity of extrapyramidal symptoms can be increased when Promethazine is combined with Procarbazine.
Ergoloid Mesylates Ergoloid Mesylates The risk or severity of adverse effects can be increased when Ergoloid mesylate is combined with Promethazine.
Tetracycline Tetracycline Tetracycline may decrease the excretion rate of Promethazine which could result in a higher serum level.
Minocycline Minocycline Minocycline may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Prochlorperazine Prochlorperazine The risk or severity of adverse effects can be increased when Prochlorperazine is combined with Promethazine.
Thioridazine Thioridazine The metabolism of Promethazine can be decreased when combined with Thioridazine.
Trifluoperazine Trifluoperazine The risk or severity of adverse effects can be increased when Trifluoperazine is combined with Promethazine.
Bleomycin Bleomycin Bleomycin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Dapsone Dapsone The risk or severity of QTc prolongation can be increased when Dapsone is combined with Promethazine.
Sulfadiazine Sulfadiazine Sulfadiazine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Oxycodone Oxycodone The risk or severity of adverse effects can be increased when Promethazine is combined with Oxycodone.
Methadone Methadone The risk or severity of adverse effects can be increased when Methadone is combined with Promethazine.
Oxybutynin Oxybutynin Promethazine may increase the central nervous system depressant (CNS depressant) activities of Oxybutynin.
Benztropine Benztropine The risk or severity of adverse effects can be increased when Promethazine is combined with Benzatropine.
Maprotiline Maprotiline Maprotiline may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Ibuprofen Ibuprofen The metabolism of Ibuprofen can be decreased when combined with Promethazine.
Trihexyphenidyl Trihexyphenidyl Promethazine may increase the central nervous system depressant (CNS depressant) activities of Trihexyphenidyl.
Orphenadrine Orphenadrine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine.
Perphenazine Perphenazine The risk or severity of adverse effects can be increased when Perphenazine is combined with Promethazine.
Azathioprine Azathioprine Azathioprine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Fluphenazine Fluphenazine The risk or severity of adverse effects can be increased when Fluphenazine is combined with Promethazine.
Phentermine Phentermine Phentermine may decrease the sedative and stimulatory activities of Promethazine.
Methylphenidate Methylphenidate The therapeutic efficacy of Methylphenidate can be decreased when used in combination with Promethazine.
Amoxapine Amoxapine The serum concentration of Amoxapine can be increased when it is combined with Promethazine.
Sulfasalazine Sulfasalazine Sulfasalazine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Hydrocortisone Hydrocortisone The metabolism of Promethazine can be increased when combined with Hydrocortisone.
Doxorubicin Doxorubicin The metabolism of Promethazine can be decreased when combined with Doxorubicin.
Mechlorethamine Mechlorethamine The therapeutic efficacy of Promethazine can be decreased when used in combination with Mechlorethamine.
Pyridostigmine Pyridostigmine The therapeutic efficacy of Promethazine can be decreased when used in combination with Pyridostigmine.
Phenazopyridine Phenazopyridine Phenazopyridine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Carbamazepine Carbamazepine Carbamazepine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Molindone Molindone The risk or severity of adverse effects can be increased when Promethazine is combined with Molindone.
Methyldopa Methyldopa Methyldopa may decrease the excretion rate of Promethazine which could result in a higher serum level.
Clonidine Clonidine The risk or severity of sedation can be increased when Clonidine is combined with Promethazine.
Hydralazine Hydralazine Promethazine may decrease the excretion rate of Hydralazine which could result in a higher serum level.
Cimetidine Cimetidine The metabolism of Cimetidine can be decreased when combined with Promethazine.
Gentamicin Injection Gentamicin Injection Gentamicin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Warfarin Warfarin The metabolism of Warfarin can be decreased when combined with Promethazine.
Clonazepam Clonazepam The risk or severity of adverse effects can be increased when Clonazepam is combined with Promethazine.
Loperamide Loperamide The metabolism of Loperamide can be decreased when combined with Promethazine.
Meclofenamate Meclofenamate Meclofenamic acid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Nitrofurantoin Nitrofurantoin Nitrofurantoin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Digoxin Digoxin Digoxin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Loxapine Loxapine The risk or severity of adverse effects can be increased when Loxapine is combined with Promethazine.
Chloroquine Chloroquine The metabolism of Promethazine can be decreased when combined with Chloroquine.
Quinine Quinine The metabolism of Promethazine can be decreased when combined with Quinine.
Ethosuximide Ethosuximide The risk or severity of adverse effects can be increased when Ethosuximide is combined with Promethazine.
Triamterene Triamterene Triamterene may decrease the excretion rate of Promethazine which could result in a higher serum level.
Lactulose Lactulose The therapeutic efficacy of Lactulose can be decreased when used in combination with Promethazine.
Sulfinpyrazone Sulfinpyrazone The metabolism of Promethazine can be increased when combined with Sulfinpyrazone.
Chlorothiazide Chlorothiazide Promethazine may increase the excretion rate of Chlorothiazide which could result in a lower serum level and potentially a reduction in efficacy.
Chlorthalidone Chlorthalidone Promethazine may increase the excretion rate of Chlorthalidone which could result in a lower serum level and potentially a reduction in efficacy.
Metolazone Metolazone Metolazone may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Isosorbide Isosorbide Isosorbide may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Clindamycin Injection Clindamycin Injection Promethazine may increase the neurotoxic activities of Clindamycin.
Secobarbital Secobarbital The risk or severity of adverse effects can be increased when Secobarbital is combined with Promethazine.
Desipramine Desipramine The metabolism of Desipramine can be decreased when combined with Promethazine.
Amitriptyline Amitriptyline The metabolism of Amitriptyline can be decreased when combined with Promethazine.
Imipramine Imipramine The metabolism of Imipramine can be decreased when combined with Promethazine.
Probenecid Probenecid Probenecid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Quinidine Quinidine The risk or severity of QTc prolongation can be increased when Quinidine is combined with Promethazine.
Procainamide Procainamide The metabolism of Procainamide can be decreased when combined with Promethazine.
Isoniazid Isoniazid The risk or severity of serotonin syndrome can be increased when Isoniazid is combined with Promethazine.
Pyrazinamide Pyrazinamide Pyrazinamide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Disopyramide Disopyramide The risk or severity of QTc prolongation can be increased when Promethazine is combined with Disopyramide.
Valproic Acid Valproic Acid Valproic acid may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Tamoxifen Tamoxifen The metabolism of Tamoxifen can be decreased when combined with Promethazine.
Butabarbital Butabarbital The risk or severity of adverse effects can be increased when Butabarbital is combined with Promethazine.
Liothyronine Liothyronine Liothyronine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Methimazole Methimazole The metabolism of Promethazine can be decreased when combined with Methimazole.
Chlorpropamide Chlorpropamide The therapeutic efficacy of Chlorpropamide can be decreased when used in combination with Promethazine.
Glucagon Injection Glucagon Injection Promethazine may increase the gastrointestinal motility reducing activities of Glucagon.
Tolbutamide Tolbutamide The therapeutic efficacy of Tolbutamide can be decreased when used in combination with Promethazine.
Tolazamide Tolazamide The therapeutic efficacy of Tolazamide can be decreased when used in combination with Promethazine.
Cyclobenzaprine Cyclobenzaprine The risk or severity of CNS depression can be increased when Cyclobenzaprine is combined with Promethazine.
Niacin Niacin The metabolism of Promethazine can be decreased when combined with Niacin.
Baclofen Baclofen The risk or severity of adverse effects can be increased when Baclofen is combined with Promethazine.
Doxylamine Doxylamine Doxylamine may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Cyproheptadine Cyproheptadine Cyproheptadine may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Clemastine Clemastine The risk or severity of QTc prolongation can be increased when Promethazine is combined with Clemastine.
Chlorpheniramine Chlorpheniramine The risk or severity of adverse effects can be increased when Promethazine is combined with Chlorpheniramine.
Brompheniramine Brompheniramine The risk or severity of adverse effects can be increased when Dexbrompheniramine is combined with Promethazine.
Meclizine Meclizine The risk or severity of adverse effects can be increased when Meclizine is combined with Promethazine.
Ethambutol Ethambutol Ethambutol may decrease the excretion rate of Promethazine which could result in a higher serum level.
Methyclothiazide Methyclothiazide Promethazine may increase the excretion rate of Methyclothiazide which could result in a lower serum level and potentially a reduction in efficacy.
Hydrochlorothiazide Hydrochlorothiazide Hydrochlorothiazide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Dantrolene Dantrolene The risk or severity of adverse effects can be increased when Promethazine is combined with Dantrolene.
Chlorzoxazone Chlorzoxazone The risk or severity of adverse effects can be increased when Chlorzoxazone is combined with Promethazine.
Carisoprodol Carisoprodol The risk or severity of adverse effects can be increased when Carisoprodol is combined with Promethazine.
Methocarbamol Methocarbamol The risk or severity of adverse effects can be increased when Methocarbamol is combined with Promethazine.
Pyridoxine Pyridoxine Pyridoxine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Folic Acid Folic Acid Folic acid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Disulfiram Disulfiram The risk or severity of QTc prolongation can be increased when Disulfiram is combined with Promethazine.
Propranolol (Cardiovascular) Propranolol (Cardiovascular) The serum concentration of Propranolol can be increased when it is combined with Promethazine.
Nortriptyline Nortriptyline The serum concentration of Nortriptyline can be increased when it is combined with Promethazine.
Spironolactone Spironolactone Spironolactone may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Amphotericin B Injection Amphotericin B Injection Amphotericin B may decrease the excretion rate of Promethazine which could result in a higher serum level.
Phytonadione Phytonadione Phylloquinone may decrease the excretion rate of Promethazine which could result in a higher serum level.
Amikacin Injection Amikacin Injection Amikacin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Nadolol Nadolol The serum concentration of Nadolol can be increased when it is combined with Promethazine.
Butorphanol Injection Butorphanol Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Butorphanol.
Nalbuphine Injection Nalbuphine Injection The risk or severity of adverse effects can be increased when Promethazine is combined with Nalbuphine.
Allopurinol Allopurinol Allopurinol may decrease the excretion rate of Promethazine which could result in a higher serum level.
Oxytocin Injection Oxytocin Injection The risk or severity of QTc prolongation can be increased when Oxytocin is combined with Promethazine.
Trimethobenzamide Trimethobenzamide Trimethobenzamide may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Flavoxate Flavoxate Promethazine may increase the central nervous system depressant (CNS depressant) activities of Flavoxate.
Papaverine Papaverine The risk or severity of QTc prolongation can be increased when Promethazine is combined with Papaverine.
Fluorouracil Injection Fluorouracil Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Fluorouracil.
Colchicine Colchicine The metabolism of Promethazine can be decreased when combined with Colchicine.
Cefaclor Cefaclor Cefaclor may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cefadroxil Cefadroxil Cefadroxil may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cefazolin Injection Cefazolin Injection Cefazolin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cephalexin Cephalexin Cephalexin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cefoxitin Injection Cefoxitin Injection Cefoxitin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Dacarbazine Dacarbazine Dacarbazine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Acetazolamide Acetazolamide The risk or severity of adverse effects can be increased when Acetazolamide is combined with Promethazine.
Cefotaxime Injection Cefotaxime Injection Cefotaxime may decrease the excretion rate of Promethazine which could result in a higher serum level.
Calcitonin Salmon Injection Calcitonin Salmon Injection Salmon calcitonin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Ketoconazole Ketoconazole Promethazine can cause a decrease in the absorption of Ketoconazole resulting in a reduced serum concentration and potentially a decrease in efficacy.
Pyrantel Pyrantel The risk or severity of adverse effects can be increased when Promethazine is combined with Pyrantel.
Thiotepa Injection Thiotepa Injection The metabolism of Promethazine can be decreased when combined with Thiotepa.
Vincristine Injection Vincristine Injection Vincristine may increase the neurotoxic activities of Promethazine.
Isoxsuprine Isoxsuprine The risk or severity of Tachycardia can be increased when Promethazine is combined with Isoxsuprine.
Vinblastine Vinblastine The metabolism of Promethazine can be decreased when combined with Vinblastine.
Ethacrynic Acid Ethacrynic Acid Etacrynic acid may decrease the excretion rate of Promethazine which could result in a higher serum level.
Colistimethate Injection Colistimethate Injection Colistimethate may decrease the excretion rate of Promethazine which could result in a higher serum level.
Metoprolol Metoprolol The metabolism of Metoprolol can be decreased when combined with Promethazine.
Hydroxyzine Hydroxyzine The risk or severity of QTc prolongation can be increased when Hydroxyzine is combined with Promethazine.
Thiothixene Thiothixene Promethazine may increase the central nervous system depressant (CNS depressant) activities of Thiothixene.
Aspirin Aspirin The metabolism of Acetylsalicylic acid can be decreased when combined with Promethazine.
Salsalate Salsalate Salsalate may decrease the excretion rate of Promethazine which could result in a higher serum level.
Alprazolam Alprazolam The risk or severity of adverse effects can be increased when Alprazolam is combined with Promethazine.
Temazepam Temazepam The risk or severity of adverse effects can be increased when Temazepam is combined with Promethazine.
Triazolam Triazolam The risk or severity of adverse effects can be increased when Triazolam is combined with Promethazine.
Dicyclomine Dicyclomine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Dicyclomine.
Hyoscyamine Hyoscyamine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Hyoscyamine.
Propantheline Propantheline Promethazine may increase the central nervous system depressant (CNS depressant) activities of Propantheline.
Trimethoprim Trimethoprim The metabolism of Trimethoprim can be decreased when combined with Promethazine.
Diltiazem Diltiazem The metabolism of Diltiazem can be decreased when combined with Promethazine.
Nifedipine Nifedipine The metabolism of Nifedipine can be decreased when combined with Promethazine.
Timolol Timolol The metabolism of Timolol can be decreased when combined with Promethazine.
Verapamil Verapamil The metabolism of Verapamil can be decreased when combined with Promethazine.
Atenolol Atenolol The serum concentration of Atenolol can be increased when it is combined with Promethazine.
Pindolol Pindolol The serum concentration of Pindolol can be increased when it is combined with Promethazine.
Cisplatin Injection Cisplatin Injection Cisplatin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Diflunisal Diflunisal Diflunisal may decrease the excretion rate of Promethazine which could result in a higher serum level.
Piroxicam Piroxicam Piroxicam may decrease the excretion rate of Promethazine which could result in a higher serum level.
Bumetanide Bumetanide Bumetanide may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Glyburide Glyburide The therapeutic efficacy of Glyburide can be decreased when used in combination with Promethazine.
Glipizide Glipizide The therapeutic efficacy of Glipizide can be decreased when used in combination with Promethazine.
Indapamide Indapamide Indapamide may increase the excretion rate of Promethazine which could result in a lower serum level and potentially a reduction in efficacy.
Amoxicillin Amoxicillin Amoxicillin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Oxacillin Injection Oxacillin Injection Oxacillin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Pentoxifylline Pentoxifylline Pentoxifylline may decrease the excretion rate of Promethazine which could result in a higher serum level.
Pentamidine Injection Pentamidine Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Pentamidine.
Ceftriaxone Injection Ceftriaxone Injection Ceftriaxone may decrease the excretion rate of Promethazine which could result in a higher serum level.
Labetalol Labetalol The serum concentration of Labetalol can be increased when it is combined with Promethazine.
Auranofin Auranofin Auranofin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Leuprolide Injection Leuprolide Injection The risk or severity of QTc prolongation can be increased when Promethazine is combined with Leuprolide.
Gemfibrozil Gemfibrozil Promethazine may decrease the excretion rate of Gemfibrozil which could result in a higher serum level.
Guanabenz Guanabenz The risk or severity of Tachycardia can be increased when Guanabenz is combined with Promethazine.
Dipivefrin Ophthalmic Dipivefrin Ophthalmic Adefovir dipivoxil may decrease the excretion rate of Promethazine which could result in a higher serum level.
Ceftazidime Injection Ceftazidime Injection Ceftazidime may decrease the excretion rate of Promethazine which could result in a higher serum level.
Ketoprofen Ketoprofen Ketoprofen may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cefotetan Injection Cefotetan Injection Cefotetan may decrease the excretion rate of Promethazine which could result in a higher serum level.
Pimozide Pimozide The metabolism of Pimozide can be decreased when combined with Promethazine.
Flurbiprofen Flurbiprofen Flurbiprofen may decrease the excretion rate of Promethazine which could result in a higher serum level.
Amiodarone Amiodarone The risk or severity of QTc prolongation can be increased when Amiodarone is combined with Promethazine.
Aztreonam Injection Aztreonam Injection Aztreonam may decrease the excretion rate of Promethazine which could result in a higher serum level.
Buspirone Buspirone The risk or severity of serotonin syndrome can be increased when Buspirone is combined with Promethazine.
Lovastatin Lovastatin The metabolism of Promethazine can be decreased when combined with Lovastatin.
Ciprofloxacin Ciprofloxacin The risk or severity of QTc prolongation can be increased when Ciprofloxacin is combined with Promethazine.
Mesalamine Mesalamine The therapeutic efficacy of Mesalazine can be decreased when used in combination with Promethazine.
Diclofenac Diclofenac Diclofenac may decrease the excretion rate of Promethazine which could result in a higher serum level.
Fluoxetine Fluoxetine The serum concentration of Promethazine can be increased when it is combined with Fluoxetine.
Nimodipine Nimodipine The risk or severity of QTc prolongation can be increased when Promethazine is combined with Nimodipine.
Clozapine Clozapine The metabolism of Clozapine can be decreased when combined with Promethazine.
Estazolam Estazolam The risk or severity of adverse effects can be increased when Promethazine is combined with Estazolam.
Idarubicin Idarubicin The metabolism of Idarubicin can be decreased when combined with Promethazine.
Ofloxacin Ofloxacin The risk or severity of QTc prolongation can be increased when Promethazine is combined with Ofloxacin.
Didanosine Didanosine Didanosine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Pentostatin Injection Pentostatin Injection Pentostatin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Clarithromycin Clarithromycin The risk or severity of QTc prolongation can be increased when Promethazine is combined with Clarithromycin.
Etodolac Etodolac Etodolac may decrease the excretion rate of Promethazine which could result in a higher serum level.
Felodipine Felodipine The metabolism of Promethazine can be decreased when combined with Felodipine.
Fosinopril Fosinopril Fosinopril may decrease the excretion rate of Promethazine which could result in a higher serum level.
Nabumetone Nabumetone Nabumetone may decrease the excretion rate of Promethazine which could result in a higher serum level.
Simvastatin Simvastatin The metabolism of Simvastatin can be decreased when combined with Promethazine.
Teniposide Injection Teniposide Injection Teniposide may increase the neurotoxic activities of Promethazine.
Itraconazole Itraconazole Promethazine can cause a decrease in the absorption of Itraconazole resulting in a reduced serum concentration and potentially a decrease in efficacy.
Lisinopril Lisinopril Lisinopril may decrease the excretion rate of Promethazine which could result in a higher serum level.
Oxaprozin Oxaprozin Oxaprozin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Atovaquone Atovaquone The risk or severity of QTc prolongation can be increased when Atovaquone is combined with Promethazine.
Rifabutin Rifabutin The metabolism of Promethazine can be increased when combined with Rifabutin.
Sotalol Sotalol The metabolism of Sotalol can be decreased when combined with Promethazine.
Bisoprolol Bisoprolol The serum concentration of Bisoprolol can be increased when it is combined with Promethazine.
Zolpidem Zolpidem Promethazine may increase the central nervous system depressant (CNS depressant) activities of Zolpidem.
Doxazosin Doxazosin The metabolism of Doxazosin can be decreased when combined with Promethazine.
Isradipine Isradipine The risk or severity of QTc prolongation can be increased when Isradipine is combined with Promethazine.
Omeprazole Omeprazole The metabolism of Omeprazole can be decreased when combined with Promethazine.
Cisapride Cisapride The metabolism of Promethazine can be decreased when combined with Cisapride.
Gabapentin Gabapentin The risk or severity of adverse effects can be increased when Gabapentin is combined with Promethazine.
Fluvastatin Fluvastatin The metabolism of Fluvastatin can be decreased when combined with Promethazine.
Venlafaxine Venlafaxine The metabolism of Promethazine can be decreased when combined with Venlafaxine.
Nizatidine Nizatidine The therapeutic efficacy of Promethazine can be decreased when used in combination with Nizatidine.
Stavudine Stavudine Stavudine may increase the neurotoxic activities of Promethazine.
Fluvoxamine Fluvoxamine The metabolism of Fluvoxamine can be decreased when combined with Promethazine.
Nefazodone Nefazodone The risk or severity of adverse effects can be increased when Promethazine is combined with Nefazodone.
Lamotrigine Lamotrigine Lamotrigine may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Losartan Losartan The metabolism of Losartan can be decreased when combined with Promethazine.
Valacyclovir Valacyclovir Valaciclovir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Tramadol Tramadol The risk or severity of serotonin syndrome can be increased when Promethazine is combined with Tramadol.
Vinorelbine Injection Vinorelbine Injection The metabolism of Promethazine can be decreased when combined with Vinorelbine.
Carboplatin Injection Carboplatin Injection Carboplatin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Moexipril Moexipril The risk or severity of QTc prolongation can be increased when Moexipril is combined with Promethazine.
Lansoprazole Lansoprazole The metabolism of Lansoprazole can be decreased when combined with Promethazine.
Ifosfamide Injection Ifosfamide Injection The metabolism of Ifosfamide can be decreased when combined with Promethazine.
Nicardipine Nicardipine The metabolism of Nicardipine can be decreased when combined with Promethazine.
Bupropion Bupropion The risk or severity of seizure can be increased when Bupropion is combined with Promethazine.
Ticlopidine Ticlopidine The metabolism of Promethazine can be decreased when combined with Ticlopidine.
Saquinavir Saquinavir Promethazine can cause an increase in the absorption of Saquinavir resulting in an increased serum concentration and potentially a worsening of adverse effects.
Metformin Metformin Metformin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Nisoldipine Nisoldipine Nisoldipine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Lamivudine Lamivudine Lamivudine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Riluzole Riluzole The risk or severity of adverse effects can be increased when Riluzole is combined with Promethazine.
Acarbose Acarbose Acarbose may decrease the excretion rate of Promethazine which could result in a higher serum level.
Glimepiride Glimepiride The therapeutic efficacy of Glimepiride can be decreased when used in combination with Promethazine.
Gemcitabine Injection Gemcitabine Injection Gemcitabine may decrease the excretion rate of Promethazine which could result in a higher serum level.
Indinavir Indinavir Promethazine can cause a decrease in the absorption of Indinavir resulting in a reduced serum concentration and potentially a decrease in efficacy.
Ritonavir Ritonavir The metabolism of Promethazine can be decreased when combined with Ritonavir.
Cidofovir Injection Cidofovir Injection Cidofovir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Meropenem Injection Meropenem Injection Meropenem may decrease the excretion rate of Promethazine which could result in a higher serum level.
Clomipramine Clomipramine The serum concentration of Clomipramine can be increased when it is combined with Promethazine.
Zafirlukast Zafirlukast The metabolism of Zafirlukast can be decreased when combined with Promethazine.
Fosfomycin Fosfomycin Fosfomycin may decrease the excretion rate of Promethazine which could result in a higher serum level.
Mirtazapine Mirtazapine Promethazine may increase the serotonergic activities of Mirtazapine.
Topiramate Topiramate The risk or severity of hyperthermia and oligohydrosis can be increased when Promethazine is combined with Topiramate.
Zileuton Zileuton The metabolism of Zileuton can be decreased when combined with Promethazine.
Valsartan Valsartan The metabolism of Valsartan can be decreased when combined with Promethazine.
Pramipexole Pramipexole The therapeutic efficacy of Pramipexole can be decreased when used in combination with Promethazine.
Donepezil Donepezil The therapeutic efficacy of Promethazine can be decreased when used in combination with Donepezil.
Nelfinavir Nelfinavir Promethazine can cause a decrease in the absorption of Nelfinavir resulting in a reduced serum concentration and potentially a decrease in efficacy.
Azithromycin Azithromycin The risk or severity of QTc prolongation can be increased when Promethazine is combined with Azithromycin.
Loratadine Loratadine Promethazine may increase the anticholinergic activities of Loratadine.
Carvedilol Carvedilol The serum concentration of Carvedilol can be increased when it is combined with Promethazine.
Nilutamide Nilutamide Nilutamide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Flutamide Flutamide Flutamide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Selegiline Selegiline The risk or severity of extrapyramidal symptoms can be increased when Promethazine is combined with Selegiline.
Bicalutamide Bicalutamide The metabolism of Promethazine can be decreased when combined with Bicalutamide.
Sertraline Sertraline The metabolism of Sertraline can be decreased when combined with Promethazine.
Propafenone Propafenone The metabolism of Promethazine can be decreased when combined with Propafenone.
Raloxifene Raloxifene The metabolism of Promethazine can be decreased when combined with Raloxifene.
Irbesartan Irbesartan The metabolism of Irbesartan can be decreased when combined with Promethazine.
Tamsulosin Tamsulosin The metabolism of Tamsulosin can be decreased when combined with Promethazine.
Ropinirole Ropinirole The therapeutic efficacy of Ropinirole can be decreased when used in combination with Promethazine.
Quetiapine Quetiapine Promethazine may increase the central nervous system depressant (CNS depressant) activities of Quetiapine.
Cefepime Injection Cefepime Injection Cefepime may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cefprozil Cefprozil Cefprozil may decrease the excretion rate of Promethazine which could result in a higher serum level.
Cefpodoxime Cefpodoxime Promethazine can cause a decrease in the absorption of Cefpodoxime resulting in a reduced serum concentration and potentially a decrease in efficacy.
Cetirizine Cetirizine The risk or severity of adverse effects can be increased when Cetirizine is combined with Promethazine.
Paroxetine Paroxetine The metabolism of Promethazine can be decreased when combined with Paroxetine.
Tolcapone Tolcapone The risk or severity of adverse effects can be increased when Tolcapone is combined with Promethazine.
Citalopram Citalopram The risk or severity of adverse effects can be increased when Promethazine is combined with Citalopram.
Capecitabine Capecitabine The metabolism of Capecitabine can be decreased when combined with Promethazine.
Efavirenz Efavirenz The risk or severity of adverse effects can be increased when Efavirenz is combined with Promethazine.
Abacavir Abacavir Abacavir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Sildenafil Sildenafil The metabolism of Sildenafil can be decreased when combined with Promethazine.
Celecoxib Celecoxib The metabolism of Promethazine can be decreased when combined with Celecoxib.
Rosiglitazone Rosiglitazone The metabolism of Rosiglitazone can be decreased when combined with Promethazine.
Tolterodine Tolterodine The metabolism of Tolterodine can be decreased when combined with Promethazine.
Thalidomide Thalidomide Promethazine may increase the central nervous system depressant (CNS depressant) activities of Thalidomide.
Oseltamivir Oseltamivir Oseltamivir may decrease the excretion rate of Promethazine which could result in a higher serum level.
Aluminum Hydroxide Aluminum Hydroxide Aluminum hydroxide can cause a decrease in the absorption of Promethazine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Balsalazide Balsalazide Balsalazide may decrease the excretion rate of Promethazine which could result in a higher serum level.
Nateglinide Nateglinide The metabolism of Nateglinide can be decreased when combined with Promethazine.
Galantamine Galantamine The risk or severity of QTc prolongation can be increased when Galantamine is combined with Promethazine.
Levetiracetam Levetiracetam Levetiracetam may increase the central nervous system depressant (CNS depressant) activities of Promethazine.
Rabeprazole Rabeprazole Promethazine may decrease the excretion rate of Rabeprazole which could result in a higher serum level.
Terbinafine Terbinafine The metabolism of Terbinafine can be decreased when combined with Promethazine.

Content provided by: AHFS® Patient Medication Information™. © Copyright, 2021. The American Society of Health-System Pharmacists