Dextromethorphan

Dextromethorphan is used to temporarily relieve cough caused by the common cold, the flu, or other conditions. Dextromethorphan will relieve a cough but will not treat the cause of the cough or speed recovery. Dextromethorphan is in a class of medications called antitussives. It works by decreasing activity in the part of the brain that causes coughing.

Dextromethorphan comes as a liquid-filled capsule, a chewable tablet, a dissolving strip, a solution (liquid), an extended-release (long-acting) suspension (liquid), and a lozenge to take by mouth. It is usually taken every 4 to 12 hours as needed. Follow the directions on the package or prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand.

Dextromethorphan should only be used according to the label or package directions. Do not take more than the recommended amount of dextromethorphan in a 24-hour period. Refer to the package or prescription label to determine the amount contained in each dose. Taking dextromethorphan in large amounts can cause serious side effects or death.

Dextromethorphan comes alone and in combination with antihistamines, cough suppressants, and decongestants. Ask your doctor or pharmacist for advice on which product is best for your symptoms. Check nonprescription cough and cold product labels carefully before using 2 or more products at the same time. These products may contain the same active ingredient(s) and taking them together could cause you to receive an overdose. This is especially important if you will be giving cough and cold medications to a child.

Nonprescription cough and cold combination products, including products that contain dextromethorphan, can cause serious side effects or death in young children. Do not give these products to children younger than 4 years of age. If you give these products to children 4-11 years of age, use caution and follow the package directions carefully.

If you are giving dextromethorphan or a combination product that contains dextromethorphan to a child, read the package label carefully to be sure that it is the right product for a child of that age. Do not give dextromethorphan products that are made for adults to children.

Before you give a dextromethorphan product to a child, check the package label to find out how much medication the child should receive. Give the dose that matches the child's age on the chart. Ask the child's doctor if you don't know how much medication to give the child.

If you are taking the 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.

If you are using the dissolving strips, place them on your tongue and swallow after they melt.

If you are taking the chewable tablets you can allow them to melt in your mouth or you can chew them before swallowing.

If you are taking the extended-release suspension, shake the bottle well before each use to mix the medication evenly.

If you are taking the lozenges, allow them to slowly melt in your mouth.

Stop taking dextromethorphan and call your doctor if your cough does not get better within 7 days, if your cough goes away and comes back, or if your cough occurs with a fever, rash, or headache.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking dextromethorphan,

• tell your doctor and pharmacist if you are allergic to dextromethorphan, any other medications, or any of the ingredients in the product you plan to take. Check the package label for a list of the ingredients.

• do not take dextromethorphan if you are taking a monoamine oxidase (MAO) inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate), or if you have stopped taking an MAO inhibitor within the past 2 weeks.

• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.

• tell your doctor if you smoke, if you have a cough that occurs with a large amount of phlegm (mucus), or if you have or have ever had breathing problems such as asthma, emphysema, or chronic bronchitis.

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

• if you have phenylketonuria (PKU, an inherited condition in which a special diet must be followed to prevent damage to your brain that can cause severe intellectual disability), you should know that some brands of chewable tablets that contain dextromethorphan may be sweetened with aspartame, a source of phenylalanine.

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

Dextromethorphan is usually taken as needed. If your doctor has told you to take dextromethorphan regularly, 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.

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

  • dizziness

  • lightheadedness

  • drowsiness

  • nervousness

  • restlessness

  • nausea

  • vomiting

  • stomach pain

• If you experience any of the following symptoms, call your doctor immediately:

  • rash

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

• 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).

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

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:

• nausea

• vomiting

• drowsiness

• dizziness

• unsteadiness

• changes in vision

• difficulty breathing

• fast heartbeat

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

• seizures

• coma (loss of consciousness for a period of time)

Ask your pharmacist any questions you have about dextromethorphan.

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.

• Alka-Seltzer Plus Cold and Cough Formula^® (containing Aspirin, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• Alka-Seltzer Plus Day and Night Cold Formulas^® (containing Aspirin, Dextromethorphan, Phenylephrine)
• Alka-Seltzer Plus Day Non-Drowsy Cold Formula^® (containing Acetaminophen, Dextromethorphan, Phenylephrine)
• Alka-Seltzer Plus Flu Formula^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• Alka-Seltzer Plus Mucus and Congestion^® (containing Dextromethorphan, Guaifenesin)
• Alka-Seltzer Plus Night Cold Formula^® (containing Aspirin, Dextromethorphan, Doxylamine, Phenylephrine)
• Children's Dimetapp Cold and Cough^® (containing Brompheniramine, Dextromethorphan, Phenylephrine)
• Children's Dimetapp Multisymptom Cold and Flu^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• Children's Mucinex Cough^® (containing Dextromethorphan, Guaifenesin)
• Children's Mucinex Multi-Symptom Cold^® (containing Dextromethorphan, Guaifenesin, Phenylephrine)
• Children's Robitussin Cough and Cold CF^® (containing Dextromethorphan, Guaifenesin, Phenylephrine)
• Children's Robitussin Cough and Cold Long-Acting^® (containing Chlorpheniramine, Dextromethorphan)
• Children's Sudafed PE Cold and Cough^® (containing Dextromethorphan, Phenylephrine)
• Coricidin HBP Chest Congestion and Cough^® (containing Dextromethorphan, Guaifenesin)
• Coricidin HBP Cough and Cold^® (containing Chlorpheniramine, Dextromethorphan)
• Coricidin HBP Day and Night Multi-Symptom Cold^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Guaifenesin)
• Coricidin HBP Maximum Strength Flu^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan)
• Coricidin HBP Nighttime Multi-Symptom Cold^® (containing Acetaminophen, Dextromethorphan, Doxylamine)
• Diabetic Tussin DM^® (containing Dextromethorphan, Guaifenesin)
• Dimetane DX^® (containing Brompheniramine, Dextromethorphan, Pseudoephedrine)
• Mucinex Cough for Kids^® (containing Dextromethorphan, Guaifenesin)
• Mucinex DM^® (containing Dextromethorphan, Guaifenesin)
• PediaCare Children's Cough and Congestion^® (containing Dextromethorphan, Guaifenesin)
• PediaCare Children's Fever Reducer Plus Cough and Runny Nose^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan)
• PediaCare Children's Fever Reducer Plus Cough and Sore Throat^® (containing Acetaminophen, Dextromethorphan)
• PediaCare Children's Fever Reducer Plus Flu^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• PediaCare Children's Fever Reducer Plus Multi-Symptom Cold^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• Robitussin Cough and Chest DM^® (containing Dextromethorphan, Guaifenesin)
• Robitussin Cough and Cold CF^® (containing Dextromethorphan, Guaifenesin, Phenylephrine)
• Robitussin Cough and Cold Long-Acting^® (containing Chlorpheniramine, Dextromethorphan)
• Robitussin Night Time Cough, Cold, and Flu^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• Sudafed PE Cold/Cough^® (containing Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine)
• Sudafed PE Day/Night Cold^® (containing Acetaminophen, Dextromethorphan, Diphenhydramine, Guaifenesin, Phenylephrine)
• Theraflu Cold and Cough^® (containing Dextromethorphan, Pheniramine, Phenylephrine)
• Theraflu Daytime Severe Cold and Cough^® (containing Acetaminophen, Dextromethorphan, Phenylephrine)
• Theraflu Max-D Severe Cold and Flu^® (containing Acetaminophen, Dextromethorphan, Guaifenesin, Pseudoephedrine)
• Triaminic Cough and Sore Throat^® (containing Acetaminophen, Dextromethorphan)
• Triaminic Day Time Cold and Cough^® (containing Dextromethorphan, Phenylephrine)
• Triaminic Multi-Symptom Fever^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan)
• Tussin DM^® (containing Dextromethorphan, Guaifenesin)
• Tylenol Cold and Cough Daytime^® (containing Acetaminophen, Dextromethorphan)
• Tylenol Cold and Cough Nighttime^® (containing Acetaminophen, Dextromethorphan, Doxylamine)
• Tylenol Cold and Flu Severe^® (containing Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine)
• Tylenol Cold and Mucus Severe^® (containing Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine)
• Tylenol Cold Multi-Symptom Nighttime^® (containing Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylephrine)
• Vicks Children's NyQuil Cold and Cough^® (containing Chlorpheniramine, Dextromethorphan)
• Vicks DayQuil Cold and Flu Relief^® (containing Acetaminophen, Dextromethorphan, Phenylephrine)
• Vicks DayQuil Cold and Flu Symptom Relief Plus Vitamin C^® (containing Acetaminophen, Dextromethorphan, Phenylephrine)
• Vicks DayQuil Mucus Control DM^® (containing Dextromethorphan, Guaifenesin)

• DM

Drug	Interaction
Montelukast	Montelukast The metabolism of Dextromethorphan can be decreased when combined with Montelukast.
Leflunomide	Leflunomide The metabolism of Dextromethorphan can be decreased when combined with Leflunomide.
Delavirdine	Delavirdine The metabolism of Dextromethorphan can be decreased when combined with Delavirdine.
Nevirapine	Nevirapine The metabolism of Dextromethorphan can be decreased when combined with Nevirapine.
Atorvastatin	Atorvastatin The metabolism of Atorvastatin can be decreased when combined with Dextromethorphan.
Dolasetron	Dolasetron The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Dolasetron.
Bisacodyl	Bisacodyl The therapeutic efficacy of Bisacodyl can be decreased when used in combination with Dextromethorphan.
Candesartan	Candesartan The metabolism of Dextromethorphan can be decreased when combined with Candesartan.
Cilostazol	Cilostazol The metabolism of Cilostazol can be decreased when combined with Dextromethorphan.
Clopidogrel	Clopidogrel The metabolism of Clopidogrel can be decreased when combined with Dextromethorphan.
Diphenoxylate	Diphenoxylate The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Diphenoxylate.
Erythromycin and Sulfisoxazole	Erythromycin and Sulfisoxazole The metabolism of Dextromethorphan can be decreased when combined with Erythromycin.
Fenofibrate	Fenofibrate The metabolism of Dextromethorphan can be decreased when combined with Fenofibrate.
Guanfacine	Guanfacine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Guanfacine.
Magnesium Hydroxide	Magnesium Hydroxide The therapeutic efficacy of Magnesium hydroxide can be decreased when used in combination with Dextromethorphan.
Magnesium Oxide	Magnesium Oxide The therapeutic efficacy of Magnesium oxide can be decreased when used in combination with Dextromethorphan.
Naratriptan	Naratriptan The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Naratriptan.
Paregoric	Paregoric The risk or severity of adverse effects can be increased when Morphine is combined with Dextromethorphan.
Penbutolol	Penbutolol The metabolism of Dextromethorphan can be decreased when combined with Acebutolol.
Pentazocine	Pentazocine The risk or severity of adverse effects can be increased when Dextromethorphan 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 Dextromethorphan.
Psyllium	Psyllium The therapeutic efficacy of Plantago seed can be decreased when used in combination with Dextromethorphan.
Ranitidine	Ranitidine The metabolism of Dextromethorphan can be decreased when combined with Ranitidine.
Reserpine	Reserpine The metabolism of Dextromethorphan can be increased when combined with Reserpine.
Rizatriptan	Rizatriptan The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Rizatriptan.
Sumatriptan	Sumatriptan The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Sumatriptan.
Tacrolimus	Tacrolimus The metabolism of Tacrolimus can be decreased when combined with Dextromethorphan.
Tizanidine	Tizanidine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Tizanidine.
Triamcinolone	Triamcinolone The metabolism of Dextromethorphan can be increased when combined with Triamcinolone.
Zolmitriptan	Zolmitriptan The risk or severity of adverse effects can be increased when Zolmitriptan is combined with Dextromethorphan.
Fluconazole Injection	Fluconazole Injection The metabolism of Dextromethorphan can be decreased when combined with Fluconazole.
Hydromorphone Injection	Hydromorphone Injection The risk or severity of adverse effects can be increased when Hydromorphone is combined with Dextromethorphan.
Meperidine Injection	Meperidine Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Meperidine.
Metoclopramide Injection	Metoclopramide Injection The therapeutic efficacy of Metoclopramide can be decreased when used in combination with Dextromethorphan.
Metronidazole Injection	Metronidazole Injection The metabolism of Metronidazole can be decreased when combined with Dextromethorphan.
Morphine Injection	Morphine Injection The risk or severity of adverse effects can be increased when Morphine is combined with Dextromethorphan.
Zidovudine Injection	Zidovudine Injection The metabolism of Dextromethorphan can be decreased when combined with Zidovudine.
Altretamine	Altretamine The risk or severity of serotonin syndrome can be increased when Amphetamine is combined with Dextromethorphan.
Cyclosporine	Cyclosporine The metabolism of Cyclosporine can be decreased when combined with Dextromethorphan.
Ondansetron	Ondansetron The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Ondansetron.
Granisetron	Granisetron The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Granisetron.
Torsemide	Torsemide The metabolism of Dextromethorphan can be decreased when combined with Torasemide.
Olanzapine	Olanzapine The risk or severity of adverse effects can be increased when Olanzapine is combined with Dextromethorphan.
Alosetron	Alosetron The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Alosetron.
Entacapone	Entacapone The risk or severity of adverse effects can be increased when Entacapone is combined with Dextromethorphan.
Hydroxychloroquine	Hydroxychloroquine The metabolism of Dextromethorphan can be decreased when combined with Hydroxychloroquine.
Meloxicam	Meloxicam The metabolism of Meloxicam can be decreased when combined with Dextromethorphan.
Oxcarbazepine	Oxcarbazepine The metabolism of Dextromethorphan can be increased when combined with Oxcarbazepine.
Zaleplon	Zaleplon The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Zaleplon.
Anakinra	Anakinra The metabolism of Dextromethorphan can be increased when combined with Anakinra.
Desloratadine	Desloratadine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Desloratadine.
Linezolid	Linezolid The risk or severity of serotonin syndrome can be increased when Linezolid is combined with Dextromethorphan.
Rivastigmine	Rivastigmine The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Rivastigmine.
Trimipramine	Trimipramine The metabolism of Trimipramine can be decreased when combined with Dextromethorphan.
Etanercept Injection	Etanercept Injection The metabolism of Dextromethorphan can be increased when combined with Etanercept.
Glycopyrrolate	Glycopyrrolate Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Glycopyrronium.
Modafinil	Modafinil The metabolism of Dextromethorphan can be increased when combined with Modafinil.
Sirolimus	Sirolimus The metabolism of Sirolimus can be decreased when combined with Dextromethorphan.
Dutasteride	Dutasteride The metabolism of Dutasteride can be decreased when combined with Dextromethorphan.
Epinephrine Injection	Epinephrine Injection The metabolism of Dextromethorphan can be decreased when combined with Epinephrine.
Eplerenone	Eplerenone The metabolism of Eplerenone can be decreased when combined with Dextromethorphan.
Escitalopram	Escitalopram The risk or severity of serotonin syndrome can be increased when Dextromethorphan is combined with Escitalopram.
Zonisamide	Zonisamide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Zonisamide.
Adalimumab Injection	Adalimumab Injection The metabolism of Dextromethorphan can be increased when combined with Adalimumab.
Aripiprazole	Aripiprazole The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Aripiprazole.
Atomoxetine	Atomoxetine The risk or severity of adverse effects can be increased when Atomoxetine is combined with Dextromethorphan.
Dexmethylphenidate	Dexmethylphenidate The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Dexmethylphenidate.
Atazanavir	Atazanavir The metabolism of Atazanavir can be decreased when combined with Dextromethorphan.
Almotriptan	Almotriptan The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Almotriptan.
Eletriptan	Eletriptan The risk or severity of adverse effects can be increased when Eletriptan is combined with Dextromethorphan.
Mefloquine	Mefloquine The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Mefloquine.
Polyethylene Glycol 3350	Polyethylene Glycol 3350 The therapeutic efficacy of Polyethylene glycol can be decreased when used in combination with Dextromethorphan.
Rosuvastatin	Rosuvastatin The metabolism of Rosuvastatin can be decreased when combined with Dextromethorphan.
Vardenafil	Vardenafil The metabolism of Vardenafil can be decreased when combined with Dextromethorphan.
Aprepitant	Aprepitant The metabolism of Dextromethorphan can be decreased when combined with Aprepitant.
Memantine	Memantine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Memantine.
Tegaserod	Tegaserod The metabolism of Tegaserod can be decreased when combined with Dextromethorphan.
Tadalafil	Tadalafil The metabolism of Tadalafil can be decreased when combined with Dextromethorphan.
Frovatriptan	Frovatriptan The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Frovatriptan.
Progesterone	Progesterone The metabolism of Dextromethorphan can be decreased when combined with Progesterone.
Apomorphine Injection	Apomorphine Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Apomorphine.
Infliximab Injection	Infliximab Injection The metabolism of Dextromethorphan can be increased when combined with Infliximab.
Oxandrolone	Oxandrolone The metabolism of Dextromethorphan can be decreased when combined with Oxandrolone.
Protriptyline	Protriptyline The risk or severity of adverse effects can be increased when Protriptyline is combined with Dextromethorphan.
Duloxetine	Duloxetine The metabolism of Duloxetine can be decreased when combined with Dextromethorphan.
Norethindrone	Norethindrone The metabolism of Norethisterone can be decreased when combined with Dextromethorphan.
Trospium	Trospium Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Trospium.
Bosentan	Bosentan The metabolism of Dextromethorphan can be increased when combined with Bosentan.
Cinacalcet	Cinacalcet The metabolism of Dextromethorphan can be decreased when combined with Cinacalcet.
Erlotinib	Erlotinib The metabolism of Erlotinib can be decreased when combined with Dextromethorphan.
Eszopiclone	Eszopiclone The risk or severity of CNS depression can be increased when Dextromethorphan is combined with Eszopiclone.
Solifenacin	Solifenacin Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Solifenacin.
Voriconazole	Voriconazole The metabolism of Dextromethorphan can be decreased when combined with Voriconazole.
Dextroamphetamine	Dextroamphetamine The risk or severity of serotonin syndrome can be increased when Amphetamine is combined with Dextromethorphan.
Peginterferon Alfa-2b (PEG-Intron)	Peginterferon Alfa-2b (PEG-Intron) The metabolism of Dextromethorphan can be increased when combined with Peginterferon alfa-2b.
Sodium Oxybate	Sodium Oxybate Sodium oxybate may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Isocarboxazid	Isocarboxazid The risk or severity of serotonin syndrome can be increased when Isocarboxazid is combined with Dextromethorphan.
Ramelteon	Ramelteon The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Ramelteon.
Darifenacin	Darifenacin The metabolism of Darifenacin can be decreased when combined with Dextromethorphan.
Fentanyl	Fentanyl The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Fentanyl.
Pregabalin	Pregabalin The therapeutic efficacy of Dextromethorphan can be increased when used in combination with Pregabalin.
Tipranavir	Tipranavir The metabolism of Tipranavir can be decreased when combined with Dextromethorphan.
Felbamate	Felbamate The metabolism of Dextromethorphan can be decreased when combined with Felbamate.
Ranolazine	Ranolazine The serum concentration of Dextromethorphan can be increased when it is combined with Ranolazine.
Abatacept Injection	Abatacept Injection The metabolism of Dextromethorphan can be increased when combined with Abatacept.
Rasagiline	Rasagiline The risk or severity of serotonin syndrome can be increased when Rasagiline is combined with Dextromethorphan.
Imatinib	Imatinib The metabolism of Dextromethorphan can be decreased when combined with Imatinib.
Gefitinib	Gefitinib The metabolism of Dextromethorphan can be decreased when combined with Gefitinib.
Paliperidone	Paliperidone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Paliperidone.
Bortezomib	Bortezomib The metabolism of Dextromethorphan can be decreased when combined with Bortezomib.
Lubiprostone	Lubiprostone The therapeutic efficacy of Lubiprostone can be decreased when used in combination with Dextromethorphan.
Primaquine	Primaquine The metabolism of Dextromethorphan can be decreased when combined with Primaquine.
Dimenhydrinate	Dimenhydrinate The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Dimenhydrinate.
Lisdexamfetamine	Lisdexamfetamine The risk or severity of serotonin syndrome can be increased when Dextromethorphan is combined with Lisdexamfetamine.
Nabilone	Nabilone Nabilone may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Sorafenib	Sorafenib The metabolism of Dextromethorphan can be decreased when combined with Sorafenib.
Sunitinib	Sunitinib The metabolism of Sunitinib can be decreased when combined with Dextromethorphan.
Dronabinol	Dronabinol Dronabinol may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Lapatinib	Lapatinib The metabolism of Lapatinib can be decreased when combined with Dextromethorphan.
Levocetirizine	Levocetirizine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Levocetirizine.
Dasatinib	Dasatinib The metabolism of Dasatinib can be decreased when combined with Dextromethorphan.
Mexiletine	Mexiletine The metabolism of Dextromethorphan can be decreased when combined with Mexiletine.
Armodafinil	Armodafinil The metabolism of Dextromethorphan can be increased when combined with Armodafinil.
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 Dextromethorphan.
Temsirolimus	Temsirolimus The metabolism of Temsirolimus can be decreased when combined with Dextromethorphan.
Nilotinib	Nilotinib The metabolism of Dextromethorphan can be decreased when combined with Nilotinib.
Bexarotene	Bexarotene The metabolism of Dextromethorphan can be decreased when combined with Bexarotene.
Budesonide	Budesonide The metabolism of Dextromethorphan can be increased when combined with Budesonide.
Chloramphenicol Injection	Chloramphenicol Injection The metabolism of Dextromethorphan can be decreased when combined with Chloramphenicol.
Betaine	Betaine The therapeutic efficacy of Dextromethorphan 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 Dextromethorphan is combined with Botulinum toxin type A.
RimabotulinumtoxinB Injection	RimabotulinumtoxinB Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Botulinum Toxin Type B.
Etravirine	Etravirine The metabolism of Dextromethorphan can be decreased when combined with Etravirine.
Desvenlafaxine	Desvenlafaxine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Desvenlafaxine.
Cevimeline	Cevimeline The metabolism of Dextromethorphan can be decreased when combined with Cevimeline.
Nebivolol	Nebivolol The metabolism of Nebivolol can be decreased when combined with Dextromethorphan.
Tretinoin	Tretinoin The metabolism of Tretinoin can be decreased when combined with Dextromethorphan.
Flecainide	Flecainide The metabolism of Flecainide can be decreased when combined with Dextromethorphan.
Certolizumab Injection	Certolizumab Injection The metabolism of Dextromethorphan can be increased when combined with Certolizumab pegol.
Irinotecan Injection	Irinotecan Injection The metabolism of Irinotecan can be decreased when combined with Dextromethorphan.
Praziquantel	Praziquantel The metabolism of Praziquantel can be decreased when combined with Dextromethorphan.
Rufinamide	Rufinamide The risk or severity of adverse effects can be increased when Rufinamide is combined with Dextromethorphan.
Midazolam	Midazolam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Midazolam.
Naltrexone Injection	Naltrexone Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Naltrexone.
Eltrombopag	Eltrombopag The metabolism of Dextromethorphan can be decreased when combined with Eltrombopag.
Milnacipran	Milnacipran The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Milnacipran.
Sodium Phosphate	Sodium Phosphate The therapeutic efficacy of Sodium phosphate, monobasic can be decreased when used in combination with Dextromethorphan.
Fesoterodine	Fesoterodine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Fesoterodine.
Betaxolol	Betaxolol The metabolism of Dextromethorphan can be decreased when combined with Betaxolol.
Iloperidone	Iloperidone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Iloperidone.
Prasugrel	Prasugrel The metabolism of Prasugrel can be decreased when combined with Dextromethorphan.
Lacosamide	Lacosamide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Lacosamide.
Everolimus	Everolimus The metabolism of Dextromethorphan can be decreased when combined with Everolimus.
Dronedarone	Dronedarone The metabolism of Dronedarone can be decreased when combined with Dextromethorphan.
AbobotulinumtoxinA Injection	AbobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Botulinum toxin type A.
Palonosetron Injection	Palonosetron Injection The risk or severity of adverse effects can be increased when Palonosetron is combined with Dextromethorphan.
Saxagliptin	Saxagliptin The metabolism of Saxagliptin can be decreased when combined with Dextromethorphan.
Romidepsin Injection	Romidepsin Injection The metabolism of Romidepsin can be decreased when combined with Dextromethorphan.
Tapentadol	Tapentadol Tapentadol may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Golimumab Injection	Golimumab Injection The metabolism of Dextromethorphan can be increased when combined with Golimumab.
Pazopanib	Pazopanib The metabolism of Dextromethorphan can be decreased when combined with Pazopanib.
Asenapine	Asenapine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Asenapine.
Vigabatrin	Vigabatrin The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Vigabatrin.
Pitavastatin	Pitavastatin The metabolism of Pitavastatin can be decreased when combined with Dextromethorphan.
Levonorgestrel	Levonorgestrel The metabolism of Dextromethorphan can be decreased when combined with Levonorgestrel.
Oxymorphone	Oxymorphone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Oxymorphone.
Tocilizumab Injection	Tocilizumab Injection The metabolism of Dextromethorphan can be increased when combined with Tocilizumab.
IncobotulinumtoxinA Injection	IncobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Botulinum toxin type A.
Cabazitaxel Injection	Cabazitaxel Injection The metabolism of Cabazitaxel can be decreased when combined with Dextromethorphan.
Lurasidone	Lurasidone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Lurasidone.
Vilazodone	Vilazodone The metabolism of Vilazodone can be decreased when combined with Dextromethorphan.
Terbutaline Injection	Terbutaline Injection The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Terbutaline.
Rilpivirine	Rilpivirine The metabolism of Dextromethorphan can be decreased when combined with Rilpivirine.
Cyclophosphamide Injection	Cyclophosphamide Injection The metabolism of Cyclophosphamide can be decreased when combined with Dextromethorphan.
Abiraterone	Abiraterone The metabolism of Dextromethorphan can be decreased when combined with Abiraterone.
Rivaroxaban	Rivaroxaban The metabolism of Rivaroxaban can be decreased when combined with Dextromethorphan.
Ticagrelor	Ticagrelor The metabolism of Dextromethorphan can be decreased when combined with Ticagrelor.
Clobazam	Clobazam The metabolism of Dextromethorphan can be decreased when combined with Clobazam.
Vemurafenib	Vemurafenib The metabolism of Dextromethorphan can be decreased when combined with Vemurafenib.
Vismodegib	Vismodegib The metabolism of Dextromethorphan can be decreased when combined with Vismodegib.
Ivacaftor	Ivacaftor The metabolism of Ivacaftor can be decreased when combined with Dextromethorphan.
Axitinib	Axitinib The metabolism of Axitinib can be decreased when combined with Dextromethorphan.
Crizotinib	Crizotinib The metabolism of Dextromethorphan can be decreased when combined with Crizotinib.
Cabergoline	Cabergoline The risk or severity of adverse effects can be increased when Cabergoline is combined with Dextromethorphan.
Ambrisentan	Ambrisentan The metabolism of Ambrisentan can be decreased when combined with Dextromethorphan.
Ezogabine	Ezogabine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Tiagabine.
Enzalutamide	Enzalutamide The metabolism of Enzalutamide can be increased when combined with Dextromethorphan.
Mirabegron	Mirabegron The metabolism of Mirabegron can be decreased when combined with Dextromethorphan.
Regorafenib	Regorafenib The metabolism of Dextromethorphan can be decreased when combined with Regorafenib.
Linaclotide	Linaclotide The therapeutic efficacy of Linaclotide can be decreased when used in combination with Dextromethorphan.
Cabozantinib (thyroid cancer)	Cabozantinib (thyroid cancer) The metabolism of Cabozantinib can be decreased when combined with Dextromethorphan.
Alogliptin	Alogliptin The metabolism of Alogliptin can be decreased when combined with Dextromethorphan.
Ponatinib	Ponatinib The metabolism of Ponatinib can be decreased when combined with Dextromethorphan.
Pomalidomide	Pomalidomide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Pomalidomide.
Ado-trastuzumab Emtansine Injection	Ado-trastuzumab Emtansine Injection The metabolism of Trastuzumab emtansine can be decreased when combined with Dextromethorphan.
Apixaban	Apixaban The metabolism of Apixaban can be decreased when combined with Dextromethorphan.
Dabrafenib	Dabrafenib The metabolism of Dextromethorphan can be increased when combined with Dabrafenib.
Ospemifene	Ospemifene The metabolism of Ospemifene can be decreased when combined with Dextromethorphan.
Levomilnacipran	Levomilnacipran The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Levomilnacipran.
Vortioxetine	Vortioxetine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Vortioxetine.
Perampanel	Perampanel Perampanel may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Ibrutinib	Ibrutinib The metabolism of Ibrutinib can be decreased when combined with Dextromethorphan.
Ketorolac Injection	Ketorolac Injection The metabolism of Dextromethorphan can be decreased when combined with Ketorolac.
Dapagliflozin	Dapagliflozin The metabolism of Dapagliflozin can be decreased when combined with Dextromethorphan.
Apremilast	Apremilast The metabolism of Dextromethorphan can be increased when combined with Apremilast.
Ceritinib	Ceritinib The metabolism of Dextromethorphan can be decreased when combined with Ceritinib.
Siltuximab Injection	Siltuximab Injection The metabolism of Dextromethorphan can be increased when combined with Siltuximab.
Eslicarbazepine	Eslicarbazepine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Eslicarbazepine.
Testosterone Injection	Testosterone Injection The metabolism of Testosterone can be decreased when combined with Dextromethorphan.
Oritavancin Injection	Oritavancin Injection The metabolism of Dextromethorphan can be decreased when combined with Oritavancin.
Hydrocodone	Hydrocodone Hydrocodone may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Suvorexant	Suvorexant Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Suvorexant.
Olaparib	Olaparib The metabolism of Olaparib can be decreased when combined with Dextromethorphan.
Methamphetamine	Methamphetamine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Metamfetamine.
Tasimelteon	Tasimelteon The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Tasimelteon.
Secukinumab Injection	Secukinumab Injection The metabolism of Dextromethorphan can be increased when combined with Secukinumab.
Risperidone Injection	Risperidone Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Risperidone.
Lenvatinib	Lenvatinib The metabolism of Dextromethorphan can be decreased when combined with Lenvatinib.
Naloxegol	Naloxegol The metabolism of Dextromethorphan can be decreased when combined with Naloxegol.
Panobinostat	Panobinostat The metabolism of Dextromethorphan can be decreased when combined with Panobinostat.
Haloperidol Injection	Haloperidol Injection The risk or severity of CNS depression can be increased when Dextromethorphan is combined with Haloperidol.
Flibanserin	Flibanserin The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Flibanserin.
Rolapitant	Rolapitant The metabolism of Dextromethorphan can be decreased when combined with Rolapitant.
Daclatasvir	Daclatasvir The metabolism of Daclatasvir can be decreased when combined with Dextromethorphan.
Brexpiprazole	Brexpiprazole The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Brexpiprazole.
Ziprasidone Injection	Ziprasidone Injection The risk or severity of adverse effects can be increased when Ziprasidone is combined with Dextromethorphan.
Cariprazine	Cariprazine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Cariprazine.
Eluxadoline	Eluxadoline The risk or severity of constipation can be increased when Dextromethorphan is combined with Eluxadoline.
Trabectedin Injection	Trabectedin Injection The metabolism of Trabectedin can be decreased when combined with Dextromethorphan.
Lesinurad	Lesinurad The metabolism of Lesinurad can be decreased when combined with Dextromethorphan.
Dexamethasone Injection	Dexamethasone Injection The metabolism of Dextromethorphan can be increased when combined with Dexamethasone.
Brivaracetam Injection	Brivaracetam Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Brivaracetam.
Cobicistat	Cobicistat The metabolism of Dextromethorphan can be decreased when combined with Cobicistat.
Pimavanserin	Pimavanserin The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Pimavanserin.
Rucaparib	Rucaparib The metabolism of Dextromethorphan can be decreased when combined with Rucaparib.
Doxepin (Insomnia)	Doxepin (Insomnia) Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Doxepin.
Plecanatide	Plecanatide The therapeutic efficacy of Plecanatide can be decreased when used in combination with Dextromethorphan.
Deutetrabenazine	Deutetrabenazine The metabolism of Deutetrabenazine can be decreased when combined with Dextromethorphan.
Valbenazine	Valbenazine The metabolism of Valbenazine can be decreased when combined with Dextromethorphan.
Deflazacort	Deflazacort The metabolism of Dextromethorphan can be increased when combined with Deflazacort.
Safinamide	Safinamide The risk or severity of serotonin syndrome can be increased when Safinamide is combined with Dextromethorphan.
Midostaurin	Midostaurin The metabolism of Dextromethorphan can be decreased when combined with Midostaurin.
Enasidenib	Enasidenib The metabolism of Dextromethorphan can be decreased when combined with Enasidenib.
Copanlisib Injection	Copanlisib Injection The metabolism of Copanlisib can be decreased when combined with Dextromethorphan.
Delafloxacin	Delafloxacin The metabolism of Dextromethorphan can be increased when combined with Delafloxacin.
Acalabrutinib	Acalabrutinib The metabolism of Dextromethorphan can be decreased when combined with Acalabrutinib.
Letermovir	Letermovir The metabolism of Dextromethorphan can be decreased when combined with Letermovir.
Tetrabenazine	Tetrabenazine The metabolism of Tetrabenazine can be decreased when combined with Dextromethorphan.
Buprenorphine Injection	Buprenorphine Injection Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Buprenorphine.
Apalutamide	Apalutamide The metabolism of Dextromethorphan can be increased when combined with Apalutamide.
Avatrombopag	Avatrombopag The metabolism of Dextromethorphan can be increased when combined with Avatrombopag.
Lofexidine	Lofexidine The therapeutic efficacy of Dextromethorphan can be increased when used in combination with Lofexidine.
Eliglustat	Eliglustat The metabolism of Dextromethorphan can be decreased when combined with Eliglustat.
Encorafenib	Encorafenib The metabolism of Encorafenib can be decreased when combined with Dextromethorphan.
Elagolix	Elagolix The metabolism of Elagolix can be decreased when combined with Dextromethorphan.
Doravirine	Doravirine The metabolism of Doravirine can be decreased when combined with Dextromethorphan.
Tafenoquine	Tafenoquine The metabolism of Tafenoquine can be decreased when combined with Dextromethorphan.
Cannabidiol	Cannabidiol The risk or severity of adverse effects can be increased when Cannabidiol is combined with Dextromethorphan.
Dacomitinib	Dacomitinib The metabolism of Dextromethorphan can be decreased when combined with Dacomitinib.
Stiripentol	Stiripentol The metabolism of Dextromethorphan can be decreased when combined with Stiripentol.
Gilteritinib	Gilteritinib The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Gilteritinib.
Lorlatinib	Lorlatinib The metabolism of Lorlatinib can be decreased when combined with Dextromethorphan.
Paclitaxel (with albumin) Injection	Paclitaxel (with albumin) Injection The metabolism of Paclitaxel can be decreased when combined with Dextromethorphan.
Rifamycin	Rifamycin The metabolism of Dextromethorphan can be decreased when combined with Rifamycin.
Prucalopride	Prucalopride The therapeutic efficacy of Prucalopride can be decreased when used in combination with Dextromethorphan.
Magnesium Citrate	Magnesium Citrate The therapeutic efficacy of Magnesium citrate can be decreased when used in combination with Dextromethorphan.
Emapalumab-lzsg Injection	Emapalumab-lzsg Injection The metabolism of Dextromethorphan can be increased when combined with Emapalumab.
Siponimod	Siponimod The metabolism of Siponimod can be decreased when combined with Dextromethorphan.
Erdafitinib	Erdafitinib The metabolism of Erdafitinib can be decreased when combined with Dextromethorphan.
Alpelisib	Alpelisib The serum concentration of Dextromethorphan can be decreased when it is combined with Alpelisib.
Brexanolone Injection	Brexanolone Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Brexanolone.
Solriamfetol	Solriamfetol The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Solriamfetol.
Triclabendazole	Triclabendazole The metabolism of Dextromethorphan can be decreased when combined with Triclabendazole.
Istradefylline	Istradefylline The metabolism of Istradefylline can be decreased when combined with Dextromethorphan.
Pitolisant	Pitolisant The serum concentration of Dextromethorphan can be decreased when it is combined with Pitolisant.
Fedratinib	Fedratinib The metabolism of Dextromethorphan can be decreased when combined with Fedratinib.
Phenytoin Injection	Phenytoin Injection The metabolism of Dextromethorphan can be decreased when combined with Phenytoin.
Fosphenytoin Injection	Fosphenytoin Injection The metabolism of Fosphenytoin can be decreased when combined with Dextromethorphan.
Voxelotor	Voxelotor The metabolism of Voxelotor can be decreased when combined with Dextromethorphan.
Avapritinib	Avapritinib The metabolism of Avapritinib can be decreased when combined with Dextromethorphan.
Lumateperone	Lumateperone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Lumateperone.
Lasmiditan	Lasmiditan The risk or severity of serotonin syndrome can be increased when Dextromethorphan is combined with Lasmiditan.
Cenobamate	Cenobamate The serum concentration of Dextromethorphan can be decreased when it is combined with Cenobamate.
Selumetinib	Selumetinib The metabolism of Selumetinib can be decreased when combined with Dextromethorphan.
Tucatinib	Tucatinib The metabolism of Tucatinib can be decreased when combined with Dextromethorphan.
Lemborexant	Lemborexant The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Lemborexant.
Fenfluramine	Fenfluramine The risk or severity of serotonin syndrome can be increased when Dextromethorphan is combined with Fenfluramine.
Pralsetinib	Pralsetinib The metabolism of Dextromethorphan can be decreased when combined with Pralsetinib.
Satralizumab-mwge Injection	Satralizumab-mwge Injection The serum concentration of Dextromethorphan can be decreased when it is combined with Satralizumab.
Viloxazine	Viloxazine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Viloxazine.
Theophylline	Theophylline The metabolism of Dextromethorphan can be decreased when combined with Theophylline.
Indomethacin	Indomethacin The metabolism of Dextromethorphan can be decreased when combined with Indomethacin.
Mefenamic Acid	Mefenamic Acid The metabolism of Mefenamic acid can be decreased when combined with Dextromethorphan.
Naproxen	Naproxen The metabolism of Naproxen can be decreased when combined with Dextromethorphan.
Trazodone	Trazodone The risk or severity of serotonin syndrome can be increased when Trazodone is combined with Dextromethorphan.
Hydroxyurea	Hydroxyurea The metabolism of Dextromethorphan can be decreased when combined with Hydroxyurea.
Floxuridine	Floxuridine The metabolism of Dextromethorphan can be decreased when combined with Floxuridine.
Phenobarbital	Phenobarbital The metabolism of Dextromethorphan can be decreased when combined with Phenobarbital.
Metaxalone	Metaxalone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Metaxalone.
Levorphanol	Levorphanol The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Levorphanol.
Primidone	Primidone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Primidone.
Methsuximide	Methsuximide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Methsuximide.
Diethylpropion	Diethylpropion The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Diethylpropion.
Chlorpromazine	Chlorpromazine The metabolism of Dextromethorphan can be decreased when combined with Chlorpromazine.
Diazepam	Diazepam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Diazepam.
Oxazepam	Oxazepam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Oxazepam.
Flurazepam	Flurazepam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Flurazepam.
Clorazepate	Clorazepate The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Clorazepic acid.
Lorazepam	Lorazepam The risk or severity of adverse effects can be increased when Lorazepam is combined with Dextromethorphan.
Amantadine	Amantadine The risk or severity of serotonin syndrome can be increased when Dextromethorphan is combined with Amantadine.
Codeine	Codeine The risk or severity of adverse effects can be increased when Codeine is combined with Dextromethorphan.
Meprobamate	Meprobamate The risk or severity of adverse effects can be increased when Meprobamate is combined with Dextromethorphan.
Chlordiazepoxide	Chlordiazepoxide The risk or severity of adverse effects can be increased when Chlordiazepoxide is combined with Dextromethorphan.
Bromocriptine	Bromocriptine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Bromocriptine.
Tranylcypromine	Tranylcypromine The risk or severity of serotonin syndrome can be increased when Tranylcypromine is combined with Dextromethorphan.
Phenelzine	Phenelzine The risk or severity of serotonin syndrome can be increased when Phenelzine is combined with Dextromethorphan.
Procarbazine	Procarbazine The risk or severity of serotonin syndrome can be increased when Procarbazine is combined with Dextromethorphan.
Ergoloid Mesylates	Ergoloid Mesylates The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Ergoloid mesylate.
Minocycline	Minocycline Minocycline may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Prochlorperazine	Prochlorperazine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Prochlorperazine.
Thioridazine	Thioridazine The metabolism of Dextromethorphan can be decreased when combined with Thioridazine.
Trifluoperazine	Trifluoperazine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Trifluoperazine.
Dapsone	Dapsone The metabolism of Dextromethorphan can be decreased when combined with Dapsone.
Sulfadiazine	Sulfadiazine The metabolism of Dextromethorphan can be decreased when combined with Sulfadiazine.
Oxycodone	Oxycodone The risk or severity of adverse effects can be increased when Oxycodone is combined with Dextromethorphan.
Methadone	Methadone The risk or severity of adverse effects can be increased when Methadone is combined with Dextromethorphan.
Oxybutynin	Oxybutynin The metabolism of Oxybutynin can be decreased when combined with Dextromethorphan.
Benztropine	Benztropine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Benzatropine.
Maprotiline	Maprotiline The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Maprotiline.
Ibuprofen	Ibuprofen The metabolism of Ibuprofen can be decreased when combined with Dextromethorphan.
Trihexyphenidyl	Trihexyphenidyl Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Trihexyphenidyl.
Orphenadrine	Orphenadrine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine.
Perphenazine	Perphenazine The metabolism of Dextromethorphan can be decreased when combined with Perphenazine.
Fluphenazine	Fluphenazine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Fluphenazine.
Phentermine	Phentermine The risk or severity of serotonin syndrome can be increased when Phentermine is combined with Dextromethorphan.
Amoxapine	Amoxapine The metabolism of Amoxapine can be decreased when combined with Dextromethorphan.
Hydrocortisone	Hydrocortisone The metabolism of Hydrocortisone can be decreased when combined with Dextromethorphan.
Doxorubicin	Doxorubicin The metabolism of Dextromethorphan can be decreased when combined with Doxorubicin.
Mechlorethamine	Mechlorethamine The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Mechlorethamine.
Pyridostigmine	Pyridostigmine The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Pyridostigmine.
Carbamazepine	Carbamazepine The metabolism of Carbamazepine can be decreased when combined with Dextromethorphan.
Molindone	Molindone The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Molindone.
Clonidine	Clonidine The risk or severity of sedation can be increased when Clonidine is combined with Dextromethorphan.
Cimetidine	Cimetidine The metabolism of Dextromethorphan can be decreased when combined with Cimetidine.
Warfarin	Warfarin The metabolism of Dextromethorphan can be decreased when combined with Warfarin.
Clonazepam	Clonazepam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Clonazepam.
Loperamide	Loperamide The metabolism of Loperamide can be decreased when combined with Dextromethorphan.
Daunorubicin	Daunorubicin The metabolism of Dextromethorphan can be increased when combined with Daunorubicin.
Loxapine	Loxapine The risk or severity of adverse effects can be increased when Loxapine is combined with Dextromethorphan.
Chloroquine	Chloroquine The metabolism of Chloroquine can be decreased when combined with Dextromethorphan.
Quinine	Quinine The metabolism of Dextromethorphan can be decreased when combined with Quinine.
Ethosuximide	Ethosuximide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Ethosuximide.
Lactulose	Lactulose The therapeutic efficacy of Lactulose can be decreased when used in combination with Dextromethorphan.
Sulfinpyrazone	Sulfinpyrazone The metabolism of Dextromethorphan can be decreased when combined with Sulfinpyrazone.
Chlorothiazide	Chlorothiazide The serum concentration of Chlorothiazide can be increased when it is combined with Dextromethorphan.
Chlorthalidone	Chlorthalidone The serum concentration of Chlorthalidone can be increased when it is combined with Dextromethorphan.
Metolazone	Metolazone The serum concentration of Metolazone can be increased when it is combined with Dextromethorphan.
Clindamycin Injection	Clindamycin Injection The metabolism of Clindamycin can be decreased when combined with Dextromethorphan.
Secobarbital	Secobarbital The risk or severity of adverse effects can be increased when Secobarbital is combined with Dextromethorphan.
Desipramine	Desipramine The metabolism of Desipramine can be decreased when combined with Dextromethorphan.
Amitriptyline	Amitriptyline The metabolism of Dextromethorphan can be decreased when combined with Amitriptyline.
Imipramine	Imipramine The metabolism of Imipramine can be decreased when combined with Dextromethorphan.
Probenecid	Probenecid The metabolism of Dextromethorphan can be decreased when combined with Probenecid.
Procainamide	Procainamide The metabolism of Procainamide can be decreased when combined with Dextromethorphan.
Isoniazid	Isoniazid The metabolism of Dextromethorphan can be decreased when combined with Isoniazid.
Rifampin	Rifampin The metabolism of Dextromethorphan can be increased when combined with Rifampicin.
Disopyramide	Disopyramide Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Disopyramide.
Valproic Acid	Valproic Acid The risk or severity of adverse effects can be increased when Valproic acid is combined with Dextromethorphan.
Tamoxifen	Tamoxifen The metabolism of Tamoxifen can be decreased when combined with Dextromethorphan.
Butabarbital	Butabarbital The risk or severity of adverse effects can be increased when Butabarbital is combined with Dextromethorphan.
Methimazole	Methimazole The metabolism of Dextromethorphan can be decreased when combined with Methimazole.
Chlorpropamide	Chlorpropamide The metabolism of Chlorpropamide can be decreased when combined with Dextromethorphan.
Tolbutamide	Tolbutamide The metabolism of Tolbutamide can be decreased when combined with Dextromethorphan.
Tolazamide	Tolazamide The metabolism of Tolazamide can be decreased when combined with Dextromethorphan.
Cyclobenzaprine	Cyclobenzaprine The risk or severity of CNS depression can be increased when Dextromethorphan is combined with Cyclobenzaprine.
Niacin	Niacin The metabolism of Dextromethorphan can be decreased when combined with Niacin.
Baclofen	Baclofen The risk or severity of adverse effects can be increased when Baclofen is combined with Dextromethorphan.
Cyproheptadine	Cyproheptadine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Cyproheptadine.
Clemastine	Clemastine The metabolism of Dextromethorphan can be decreased when combined with Clemastine.
Meclizine	Meclizine The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Meclizine.
Methyclothiazide	Methyclothiazide The serum concentration of Methyclothiazide can be increased when it is combined with Dextromethorphan.
Hydrochlorothiazide	Hydrochlorothiazide The serum concentration of Hydrochlorothiazide can be increased when it is combined with Dextromethorphan.
Dantrolene	Dantrolene The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Dantrolene.
Chlorzoxazone	Chlorzoxazone The risk or severity of adverse effects can be increased when Chlorzoxazone is combined with Dextromethorphan.
Carisoprodol	Carisoprodol The risk or severity of adverse effects can be increased when Carisoprodol is combined with Dextromethorphan.
Methocarbamol	Methocarbamol The risk or severity of adverse effects can be increased when Methocarbamol is combined with Dextromethorphan.
Disulfiram	Disulfiram The metabolism of Disulfiram can be decreased when combined with Dextromethorphan.
Propranolol (Cardiovascular)	Propranolol (Cardiovascular) The metabolism of Propranolol can be decreased when combined with Dextromethorphan.
Nortriptyline	Nortriptyline The metabolism of Nortriptyline can be decreased when combined with Dextromethorphan.
Nadolol	Nadolol The metabolism of Nadolol can be decreased when combined with Dextromethorphan.
Butorphanol Injection	Butorphanol Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Butorphanol.
Nalbuphine Injection	Nalbuphine Injection The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Nalbuphine.
Trimethobenzamide	Trimethobenzamide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Trimethobenzamide.
Flavoxate	Flavoxate Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Flavoxate.
Fluorouracil Injection	Fluorouracil Injection The metabolism of Dextromethorphan can be decreased when combined with Fluorouracil.
Acetazolamide	Acetazolamide The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Acetazolamide.
Ketoconazole	Ketoconazole The metabolism of Dextromethorphan can be decreased when combined with Ketoconazole.
Pyrantel	Pyrantel The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Pyrantel.
Thiotepa Injection	Thiotepa Injection The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Thiotepa.
Vincristine Injection	Vincristine Injection The metabolism of Vincristine can be decreased when combined with Dextromethorphan.
Vinblastine	Vinblastine The metabolism of Dextromethorphan can be decreased when combined with Vinblastine.
Metoprolol	Metoprolol The metabolism of Dextromethorphan can be decreased when combined with Metoprolol.
Hydroxyzine	Hydroxyzine Hydroxyzine may increase the central nervous system depressant (CNS depressant) activities of Dextromethorphan.
Thiothixene	Thiothixene The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Thiothixene.
Alprazolam	Alprazolam The risk or severity of adverse effects can be increased when Alprazolam is combined with Dextromethorphan.
Temazepam	Temazepam The risk or severity of adverse effects can be increased when Temazepam is combined with Dextromethorphan.
Triazolam	Triazolam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Triazolam.
Dicyclomine	Dicyclomine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Dicyclomine.
Hyoscyamine	Hyoscyamine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Hyoscyamine.
Propantheline	Propantheline Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Propantheline.
Trimethoprim	Trimethoprim The metabolism of Dextromethorphan can be decreased when combined with Trimethoprim.
Diltiazem	Diltiazem The metabolism of Dextromethorphan can be decreased when combined with Diltiazem.
Nifedipine	Nifedipine The metabolism of Nifedipine can be decreased when combined with Dextromethorphan.
Timolol	Timolol The metabolism of Dextromethorphan can be decreased when combined with Timolol.
Verapamil	Verapamil The metabolism of Dextromethorphan can be decreased when combined with Verapamil.
Atenolol	Atenolol The metabolism of Dextromethorphan can be decreased when combined with Atenolol.
Pindolol	Pindolol The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Pindolol.
Cisplatin Injection	Cisplatin Injection The metabolism of Dextromethorphan can be decreased when combined with Cisplatin.
Piroxicam	Piroxicam The metabolism of Piroxicam can be decreased when combined with Dextromethorphan.
Etoposide	Etoposide The metabolism of Etoposide can be decreased when combined with Dextromethorphan.
Glyburide	Glyburide The metabolism of Dextromethorphan can be decreased when combined with Glyburide.
Glipizide	Glipizide The metabolism of Glipizide can be decreased when combined with Dextromethorphan.
Indapamide	Indapamide The serum concentration of Indapamide can be increased when it is combined with Dextromethorphan.
Pentamidine Injection	Pentamidine Injection The metabolism of Pentamidine can be decreased when combined with Dextromethorphan.
Labetalol	Labetalol The metabolism of Dextromethorphan can be decreased when combined with Labetalol.
Gemfibrozil	Gemfibrozil The metabolism of Dextromethorphan can be decreased when combined with Gemfibrozil.
Pimozide	Pimozide The metabolism of Pimozide can be decreased when combined with Dextromethorphan.
Flurbiprofen	Flurbiprofen The metabolism of Flurbiprofen can be decreased when combined with Dextromethorphan.
Amiodarone	Amiodarone The serum concentration of Amiodarone can be increased when it is combined with Dextromethorphan.
Buspirone	Buspirone The risk or severity of serotonin syndrome can be increased when Buspirone is combined with Dextromethorphan.
Lovastatin	Lovastatin The metabolism of Dextromethorphan can be decreased when combined with Lovastatin.
Ciprofloxacin	Ciprofloxacin The metabolism of Dextromethorphan can be decreased when combined with Ciprofloxacin.
Diclofenac	Diclofenac The metabolism of Diclofenac can be decreased when combined with Dextromethorphan.
Fluoxetine	Fluoxetine The serum concentration of Dextromethorphan can be increased when it is combined with Fluoxetine.
Clozapine	Clozapine The metabolism of Clozapine can be decreased when combined with Dextromethorphan.
Estazolam	Estazolam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Estazolam.
Idarubicin	Idarubicin The metabolism of Idarubicin can be decreased when combined with Dextromethorphan.
Clarithromycin	Clarithromycin The metabolism of Dextromethorphan can be decreased when combined with Clarithromycin.
Etodolac	Etodolac The metabolism of Etodolac can be decreased when combined with Dextromethorphan.
Felodipine	Felodipine The metabolism of Felodipine can be decreased when combined with Dextromethorphan.
Nabumetone	Nabumetone The metabolism of Dextromethorphan can be decreased when combined with Nabumetone.
Simvastatin	Simvastatin The metabolism of Simvastatin can be decreased when combined with Dextromethorphan.
Teniposide Injection	Teniposide Injection The metabolism of Dextromethorphan can be decreased when combined with Teniposide.
Itraconazole	Itraconazole The metabolism of Dextromethorphan can be decreased when combined with Itraconazole.
Atovaquone	Atovaquone The metabolism of Dextromethorphan can be decreased when combined with Atovaquone.
Sotalol	Sotalol The metabolism of Sotalol can be decreased when combined with Dextromethorphan.
Zolpidem	Zolpidem Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Zolpidem.
Doxazosin	Doxazosin The metabolism of Doxazosin can be decreased when combined with Dextromethorphan.
Omeprazole	Omeprazole The metabolism of Dextromethorphan can be decreased when combined with Omeprazole.
Cisapride	Cisapride The metabolism of Cisapride can be decreased when combined with Dextromethorphan.
Gabapentin	Gabapentin The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Gabapentin.
Fluvastatin	Fluvastatin The metabolism of Fluvastatin can be decreased when combined with Dextromethorphan.
Venlafaxine	Venlafaxine The metabolism of Dextromethorphan can be decreased when combined with Venlafaxine.
Nizatidine	Nizatidine The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Nizatidine.
Fluvoxamine	Fluvoxamine The metabolism of Fluvoxamine can be decreased when combined with Dextromethorphan.
Nefazodone	Nefazodone The risk or severity of adverse effects can be increased when Nefazodone is combined with Dextromethorphan.
Lamotrigine	Lamotrigine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Lamotrigine.
Losartan	Losartan The metabolism of Losartan can be decreased when combined with Dextromethorphan.
Tramadol	Tramadol The risk or severity of serotonin syndrome can be increased when Tramadol is combined with Dextromethorphan.
Vinorelbine Injection	Vinorelbine Injection The metabolism of Dextromethorphan can be decreased when combined with Vinorelbine.
Lansoprazole	Lansoprazole The metabolism of Dextromethorphan can be decreased when combined with Lansoprazole.
Ifosfamide Injection	Ifosfamide Injection The metabolism of Ifosfamide can be decreased when combined with Dextromethorphan.
Nicardipine	Nicardipine The metabolism of Dextromethorphan can be decreased when combined with Nicardipine.
Bupropion	Bupropion The metabolism of Dextromethorphan can be decreased when combined with Bupropion.
Ticlopidine	Ticlopidine The metabolism of Dextromethorphan can be decreased when combined with Ticlopidine.
Saquinavir	Saquinavir The metabolism of Dextromethorphan can be decreased when combined with Saquinavir.
Nisoldipine	Nisoldipine The metabolism of Dextromethorphan can be decreased when combined with Nisoldipine.
Riluzole	Riluzole The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Riluzole.
Glimepiride	Glimepiride The metabolism of Dextromethorphan can be decreased when combined with Glimepiride.
Indinavir	Indinavir The metabolism of Dextromethorphan can be decreased when combined with Indinavir.
Ritonavir	Ritonavir The serum concentration of Dextromethorphan can be increased when it is combined with Ritonavir.
Docetaxel Injection	Docetaxel Injection The metabolism of Docetaxel can be decreased when combined with Dextromethorphan.
Clomipramine	Clomipramine The metabolism of Clomipramine can be decreased when combined with Dextromethorphan.
Zafirlukast	Zafirlukast The metabolism of Dextromethorphan can be decreased when combined with Zafirlukast.
Mirtazapine	Mirtazapine Dextromethorphan may increase the serotonergic activities of Mirtazapine.
Topiramate	Topiramate The risk or severity of adverse effects can be increased when Topiramate is combined with Dextromethorphan.
Zileuton	Zileuton The metabolism of Zileuton can be decreased when combined with Dextromethorphan.
Valsartan	Valsartan The metabolism of Dextromethorphan can be decreased when combined with Valsartan.
Pramipexole	Pramipexole Dextromethorphan may increase the sedative activities of Pramipexole.
Donepezil	Donepezil The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Donepezil.
Nelfinavir	Nelfinavir The metabolism of Dextromethorphan can be decreased when combined with Nelfinavir.
Loratadine	Loratadine Dextromethorphan may increase the anticholinergic activities of Loratadine.
Carvedilol	Carvedilol The metabolism of Carvedilol can be decreased when combined with Dextromethorphan.
Nilutamide	Nilutamide The metabolism of Dextromethorphan can be decreased when combined with Nilutamide.
Flutamide	Flutamide The metabolism of Dextromethorphan can be decreased when combined with Flutamide.
Selegiline	Selegiline The risk or severity of serotonin syndrome can be increased when Selegiline is combined with Dextromethorphan.
Bicalutamide	Bicalutamide The metabolism of Dextromethorphan can be decreased when combined with Bicalutamide.
Sertraline	Sertraline The risk or severity of adverse effects can be increased when Sertraline is combined with Dextromethorphan.
Propafenone	Propafenone The metabolism of Dextromethorphan can be decreased when combined with Propafenone.
Irbesartan	Irbesartan The metabolism of Irbesartan can be decreased when combined with Dextromethorphan.
Tamsulosin	Tamsulosin The metabolism of Tamsulosin can be decreased when combined with Dextromethorphan.
Ropinirole	Ropinirole Dextromethorphan may increase the sedative activities of Ropinirole.
Finasteride	Finasteride The metabolism of Finasteride can be decreased when combined with Dextromethorphan.
Quetiapine	Quetiapine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Quetiapine.
Cetirizine	Cetirizine The risk or severity of adverse effects can be increased when Cetirizine is combined with Dextromethorphan.
Paroxetine	Paroxetine The metabolism of Dextromethorphan can be decreased when combined with Paroxetine.
Tolcapone	Tolcapone The metabolism of Dextromethorphan can be decreased when combined with Tolcapone.
Citalopram	Citalopram The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Citalopram.
Capecitabine	Capecitabine The metabolism of Dextromethorphan can be decreased when combined with Capecitabine.
Efavirenz	Efavirenz The metabolism of Dextromethorphan can be increased when combined with Efavirenz.
Sildenafil	Sildenafil The metabolism of Dextromethorphan can be decreased when combined with Sildenafil.
Celecoxib	Celecoxib The metabolism of Dextromethorphan can be decreased when combined with Celecoxib.
Rosiglitazone	Rosiglitazone The metabolism of Dextromethorphan can be decreased when combined with Rosiglitazone.
Tolterodine	Tolterodine Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Tolterodine.
Thalidomide	Thalidomide Dextromethorphan may increase the central nervous system depressant (CNS depressant) activities of Thalidomide.
Nateglinide	Nateglinide The metabolism of Nateglinide can be decreased when combined with Dextromethorphan.
Galantamine	Galantamine The therapeutic efficacy of Dextromethorphan can be decreased when used in combination with Galantamine.
Levetiracetam	Levetiracetam The risk or severity of adverse effects can be increased when Dextromethorphan is combined with Levetiracetam.
Rabeprazole	Rabeprazole The metabolism of Dextromethorphan can be decreased when combined with Rabeprazole.
Terbinafine	Terbinafine The metabolism of Dextromethorphan can be decreased when combined with Terbinafine.