Phenytoin Injection

Generic name: Pronounced as (fen' i toyn)
Brand names
  • Dilantin®
Click on drug name to hear pronunciation

Medical Content Reviewed By HelloPharmacist Staff

Last Revised - 12/15/2019

You may experience serious or life-threatening low blood pressure or irregular heart rhythms while you are receiving phenytoin injection or afterwards. Tell your doctor if you have or have ever had irregular heart rhythms or heart block (condition in which electrical signals are not passed normally from the upper chambers of the heart to the lower chambers). Your doctor may not want you to receive phenytoin injection. Also, tell your doctor if you have or have ever had heart failure or low blood pressure. If you experience any of the following symptoms, tell your doctor immediately: dizziness, tiredness, irregular heartbeat, or chest pain.

You will receive each dose of phenytoin injection in a medical facility, and a doctor or nurse will monitor you carefully while you are receiving the medication and afterwards.

Phenytoin injection is used to treat primary generalized tonic-clonic seizures (formerly known as a grand mal seizure; seizure that involves the entire body) and to treat and prevent seizures that may begin during or after surgery to the brain or nervous system. Phenytoin injection may also be used to control certain types of seizures in people who cannot take oral phenytoin. Phenytoin is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in the brain.

Phenytoin injection comes as a solution (liquid) to be slowly injected intravenously (into a vein) by a doctor or nurse in a medical facility. It is usually injected once every 6 or 8 hours.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Phenytoin injection is also used to control irregular heartbeat. Talk to your doctor about the risks of using this medication for your condition.

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

Before receiving phenytoin injection,

  • tell your doctor and pharmacist if you are allergic to phenytoin, other hydantoin medications such as ethotoin (Peganone) or fosphenytoin (Cerebyx), any other medications, or any of the ingredients in phenytoin injection. Ask your pharmacist for a list of the ingredients.

  • tell your doctor if you are taking delavirdine (Rescriptor). Your doctor will probably not want you to receive phenytoin injection if you are taking this medication.

  • 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: albendazole (Albenza); amiodarone (Nexterone, Pacerone); anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven); antifungal medications such as fluconazole (Diflucan), ketoconazole (Nizoral), itraconazole (Onmel, Sporanox, Tolsura), miconazole (Oravig), posaconazole (Noxafil), and voriconazole (Vfend); certain antivirals such as efavirenz (Sustiva, in Atripla), indinavir (Crixivan), lopinavir (in Kaletra), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), and saquinavir (Invirase); bleomycin; capecitabine (Xeloda); carboplatin; chloramphenicol; chlordiazepoxide (Librium, in Librax); cholesterol medications such as atorvastatin (Lipitor, in Caduet), fluvastatin (Lescol), and simvastatin (Zocor, in Vytorin); cisplatin; clozapine (Fazaclo, Versacloz); cyclosporine (Gengraf, Neoral, Sandimmune); diazepam (Valium); diazoxide (Proglycem); digoxin (Lanoxin); disopyramide (Norpace); disulfiram (Antabuse); doxorubicin (Doxil); doxycycline (Acticlate, Doryx, Monodox, Oracea, Vibramycin); fluorouracil; fluoxetine (Prozac, Sarafem, in Symbyax, others); fluvoxamine (Luvox); folic acid; fosamprenavir (Lexiva); furosemide (Lasix); H2 antagonists such as cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid), and ranitidine (Zantac); hormonal contraceptives (birth control pills, patches, rings, or injections); hormone replacement therapy (HRT); irinotecan (Camptosar); isoniazid (Laniazid, in Rifamate, in Rifater); medications for mental illness and nausea; other medications for seizures such as carbamazepine (Carbatrol, Equetro, Tegretol, others), ethosuximide (Zarontin), felbamate (Felbatol), lamotrigine (Lamictal), methsuximide (Celontin), oxcarbazepine (Trilepta, Oxtellar XR), phenobarbital, topiramate (Topamax), and valproic acid (Depakene); methadone (Dolophine, Methadose); methotrexate (Otrexup, Rasuvo, Trexall, Xatmep); methylphenidate (Daytrana, Concerta, Metadate, Ritalin); mexiletine; nifedipine (Adalat, Procardia), nimodipine (Nymalize), nisoldipine (Sular); omeprazole (Prilosec); oral steroids such as dexamethasone, methylprednisolone (Medrol), prednisolone, and prednisone (Rayos); paclitaxel (Abraxane, Taxol); paroxetine (Paxil, Pexeva); praziquantel (Biltricide); quetiapine (Seroquel); quinidine (in Nuedexta); reserpine; rifampin (Rifadin, Rimactane, in Rifamate, in Rifater); salicylate pain relievers such as aspirin, choline magnesium trisalicylate, choline salicylate, diflunisal, magnesium salicylate (Doan's, others), and salsalate; sertraline (Zoloft); sulfa antibiotics; teniposide; theophylline (Elixophyllin, Theo-24, Theochron); ticlopidine; tolbutamide; trazodone; verapamil (Calan, Verelan, in Tarka); vigabatrin (Sabril); and vitamin D. Your doctor may need to change the doses of your medications or monitor you more carefully for side effects.

  • tell your doctor what herbal products you are taking, especially St. John's wort.

  • tell your doctor if you have ever developed a liver problem while taking phenytoin. Your doctor will probably not want you to receive phenytoin injection.

  • tell your doctor if you drink or have ever drunk large amounts of alcohol. Tell your doctor if you have had laboratory testing that reported you have an inherited risk factor that makes it more likely that you could have an serious skin reaction to phenytoin. Also, tell your doctor if you have or have ever had diabetes, porphyria (condition in which certain natural substances build up in the body and may cause stomach pain, changes in thinking or behavior, or other symptoms), low levels of albumin in your blood, or kidney or liver disease.

  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. You should not become pregnant while you are receiving phenytoin. Talk to your doctor about effective birth control methods that you can use during your treatment. If you become pregnant while receiving phenytoin, call your doctor. Phenytoin may harm the fetus.

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

  • you should know that this medication may cause dizziness, drowsiness, and problems with coordination. Do not drive a car or operate machinery until you know how this medication affects you.

  • talk to your doctor about the safe use of alcohol while you are taking this medication.

  • talk to your doctor about the best way to care for your teeth, gums, and mouth during your treatment with phenytoin. It is very important that you care for your mouth properly to decrease the risk of gum damage caused by phenytoin.

Phenytoin may cause an increase in your blood sugar. Talk to your doctor about the symptoms of high blood sugar and what to do if you experience these symptoms.

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

    • difficulty falling asleep or staying asleep

    • uncontrollable eye movements

    • abnormal body movements

    • loss of coordination

    • confusion

    • slurred speech

    • headache

    • changes in your sense of taste

    • constipation

    • unwanted hair growth

    • coarsening of facial features

    • enlargement of lips

    • overgrowth of gums

    • pain or curving of the penis

  • Some side effects can be serious. If you experience any of the following symptoms or those listed in the SPECIAL PRECAUTIONS section, call your doctor immediately:

    • swelling, discoloration, or pain at the injection site

    • rash

    • hives

    • itching

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

    • difficulty breathing or swallowing

    • hoarseness

    • swollen glands

    • nausea

    • vomiting

    • yellowing of the skin or eyes

    • pain in upper right part of the stomach

    • excessive tiredness

    • unusual bruising or bleeding

    • small red or purple spots on skin

    • loss of appetite

    • flu-like symptoms

    • fever, sore throat, rash, mouth ulcers, or easy bruising, or facial swelling

  • Phenytoin injection may cause other side effects. Call your doctor if you have 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).

  • Taking phenytoin may increase the risk that you will develop problems with your lymph nodes including Hodgkin's disease (cancer that begins in the lymph system). Talk to your doctor about the risks of using this medication to treat your condition.

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 the following:

  • uncontrollable eye movements

  • loss of coordination

  • slow or slurred speech

  • fatigue

  • blurred vision

  • uncontrollable shaking of a part of the body

  • nausea

  • vomiting

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your response to phenytoin injection.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving phenytoin injection.

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.

Drug Interaction
Repaglinide Repaglinide The metabolism of Repaglinide can be decreased when combined with Phenytoin.
Montelukast Montelukast The metabolism of Phenytoin can be decreased when combined with Montelukast.
Leflunomide Leflunomide The metabolism of Phenytoin can be decreased when combined with Leflunomide.
Delavirdine Delavirdine The serum concentration of Delavirdine can be decreased when it is combined with Phenytoin.
Nevirapine Nevirapine The metabolism of Nevirapine can be decreased when combined with Phenytoin.
Atorvastatin Atorvastatin The serum concentration of Atorvastatin can be decreased when it is combined with Phenytoin.
Dolasetron Dolasetron The risk or severity of adverse effects can be increased when Phenytoin is combined with Dolasetron.
Alendronate Alendronate The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Alendronic acid.
Aminophylline Aminophylline The metabolism of Aminophylline can be increased when combined with Phenytoin.
Candesartan Candesartan The metabolism of Phenytoin can be decreased when combined with Candesartan.
Cilostazol Cilostazol The metabolism of Cilostazol can be increased when combined with Phenytoin.
Clopidogrel Clopidogrel The metabolism of Clopidogrel can be decreased when combined with Phenytoin.
Diphenoxylate Diphenoxylate The risk or severity of adverse effects can be increased when Phenytoin is combined with Diphenoxylate.
Erythromycin and Sulfisoxazole Erythromycin and Sulfisoxazole The metabolism of Phenytoin can be decreased when combined with Erythromycin.
Estrogen and Progestin (Oral Contraceptives) Estrogen and Progestin (Oral Contraceptives) The therapeutic efficacy of Phenytoin can be decreased when used in combination with Conjugated estrogens.
Fenofibrate Fenofibrate The metabolism of Fenofibrate can be increased when combined with Phenytoin.
Guanfacine Guanfacine The metabolism of Guanfacine can be increased when combined with Phenytoin.
Magnesium Gluconate Magnesium Gluconate Magnesium gluconate can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium Hydroxide Magnesium Hydroxide Magnesium hydroxide can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium Oxide Magnesium Oxide Magnesium oxide can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Mycophenolate Mycophenolate The metabolism of Mycophenolic acid can be increased when combined with Phenytoin.
Nafarelin Nafarelin The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Nafarelin.
Naratriptan Naratriptan The risk or severity of adverse effects can be increased when Phenytoin is combined with Naratriptan.
Olsalazine Olsalazine The serum concentration of Phenytoin can be increased when it is combined with Olsalazine.
Paregoric Paregoric The metabolism of Phenytoin can be decreased when combined with Morphine.
Penbutolol Penbutolol The metabolism of Phenytoin can be decreased when combined with Acebutolol.
Pentazocine Pentazocine The risk or severity of adverse effects can be increased when Phenytoin is combined with Pentazocine.
Prednisone Prednisone The serum concentration of Phenytoin can be decreased when it is combined with Prednisone.
Ranitidine Ranitidine The metabolism of Phenytoin can be decreased when combined with Ranitidine.
Reserpine Reserpine The serum concentration of Phenytoin can be decreased when it is combined with Reserpine.
Rizatriptan Rizatriptan The risk or severity of adverse effects can be increased when Phenytoin is combined with Rizatriptan.
Sumatriptan Sumatriptan The risk or severity of adverse effects can be increased when Phenytoin is combined with Sumatriptan.
Tacrolimus Tacrolimus The serum concentration of Tacrolimus can be decreased when it is combined with Phenytoin.
Tizanidine Tizanidine The risk or severity of adverse effects can be increased when Phenytoin is combined with Tizanidine.
Triamcinolone Triamcinolone The serum concentration of Triamcinolone can be decreased when it is combined with Phenytoin.
Zolmitriptan Zolmitriptan The risk or severity of adverse effects can be increased when Phenytoin is combined with Zolmitriptan.
Doxycycline Injection Doxycycline Injection The serum concentration of Doxycycline can be decreased when it is combined with Phenytoin.
Fluconazole Injection Fluconazole Injection The serum concentration of Phenytoin can be increased when it is combined with Fluconazole.
Hydromorphone Injection Hydromorphone Injection The metabolism of Hydromorphone can be decreased when combined with Phenytoin.
Meperidine Injection Meperidine Injection The serum concentration of Meperidine can be decreased when it is combined with Phenytoin.
Methylprednisolone Injection Methylprednisolone Injection The serum concentration of Phenytoin can be decreased when it is combined with Methylprednisolone.
Metoclopramide Injection Metoclopramide Injection The risk or severity of sedation can be increased when Phenytoin is combined with Metoclopramide.
Metronidazole Injection Metronidazole Injection The serum concentration of Metronidazole can be decreased when it is combined with Phenytoin.
Morphine Injection Morphine Injection The metabolism of Phenytoin can be decreased when combined with Morphine.
Pamidronate Injection Pamidronate Injection The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Pamidronic acid.
Zidovudine Injection Zidovudine Injection The metabolism of Zidovudine can be decreased when combined with Phenytoin.
Altretamine Altretamine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Amphetamine.
Cyclosporine Cyclosporine The serum concentration of Cyclosporine can be decreased when it is combined with Phenytoin.
Ondansetron Ondansetron The metabolism of Ondansetron can be decreased when combined with Phenytoin.
Granisetron Granisetron The risk or severity of adverse effects can be increased when Phenytoin is combined with Granisetron.
Torsemide Torsemide The metabolism of Phenytoin can be decreased when combined with Torasemide.
Olanzapine Olanzapine The metabolism of Phenytoin can be decreased when combined with Olanzapine.
Alosetron Alosetron The metabolism of Alosetron can be decreased when combined with Phenytoin.
Dofetilide Dofetilide The metabolism of Dofetilide can be increased when combined with Phenytoin.
Entacapone Entacapone The metabolism of Entacapone can be decreased when combined with Phenytoin.
Eprosartan Eprosartan The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Eprosartan.
Hydroxychloroquine Hydroxychloroquine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Hydroxychloroquine.
Meloxicam Meloxicam The serum concentration of Meloxicam can be increased when it is combined with Phenytoin.
Orlistat Orlistat Orlistat can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Oxcarbazepine Oxcarbazepine The serum concentration of Phenytoin can be increased when it is combined with Oxcarbazepine.
Pantoprazole Pantoprazole The metabolism of Phenytoin can be decreased when combined with Pantoprazole.
Risedronate Risedronate The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Risedronic acid.
Sevelamer Sevelamer Sevelamer can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Telmisartan Telmisartan The metabolism of Phenytoin can be decreased when combined with Telmisartan.
Zaleplon Zaleplon The metabolism of Zaleplon can be increased when combined with Phenytoin.
Anakinra Anakinra The metabolism of Phenytoin can be increased when combined with Anakinra.
Desloratadine Desloratadine The risk or severity of adverse effects can be increased when Phenytoin is combined with Desloratadine.
Linezolid Linezolid The risk or severity of adverse effects can be increased when Phenytoin is combined with Linezolid.
Trimipramine Trimipramine The metabolism of Phenytoin can be decreased when combined with Trimipramine.
Etanercept Injection Etanercept Injection The metabolism of Phenytoin can be increased when combined with Etanercept.
Glycopyrrolate Glycopyrrolate Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Glycopyrronium.
Modafinil Modafinil The metabolism of Phenytoin can be decreased when combined with Modafinil.
Tenofovir Tenofovir The metabolism of Tenofovir can be increased when combined with Phenytoin.
Choline Magnesium Trisalicylate Choline Magnesium Trisalicylate The serum concentration of Phenytoin can be increased when it is combined with Choline magnesium trisalicylate.
Sirolimus Sirolimus The metabolism of Sirolimus can be increased when combined with Phenytoin.
Dutasteride Dutasteride The metabolism of Dutasteride can be increased when combined with Phenytoin.
Epinephrine Injection Epinephrine Injection The metabolism of Phenytoin can be decreased when combined with Epinephrine.
Eplerenone Eplerenone The metabolism of Eplerenone can be increased when combined with Phenytoin.
Escitalopram Escitalopram The serum concentration of Escitalopram can be increased when it is combined with Phenytoin.
Zonisamide Zonisamide Phenytoin may increase the excretion rate of Zonisamide which could result in a lower serum level and potentially a reduction in efficacy.
Adalimumab Injection Adalimumab Injection The metabolism of Phenytoin can be increased when combined with Adalimumab.
Aripiprazole Aripiprazole The metabolism of Aripiprazole can be increased when combined with Phenytoin.
Atomoxetine Atomoxetine The risk or severity of adverse effects can be increased when Phenytoin is combined with Atomoxetine.
Dexmethylphenidate Dexmethylphenidate The serum concentration of Phenytoin can be increased when it is combined with Dexmethylphenidate.
Ezetimibe Ezetimibe The metabolism of Ezetimibe can be increased when combined with Phenytoin.
Atazanavir Atazanavir The metabolism of Atazanavir can be increased when combined with Phenytoin.
Almotriptan Almotriptan The metabolism of Almotriptan can be decreased when combined with Phenytoin.
Eletriptan Eletriptan The metabolism of Eletriptan can be decreased when combined with Phenytoin.
Mefloquine Mefloquine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Mefloquine.
Rosuvastatin Rosuvastatin The metabolism of Rosuvastatin can be increased when combined with Phenytoin.
Vardenafil Vardenafil The metabolism of Vardenafil can be increased when combined with Phenytoin.
Aprepitant Aprepitant The metabolism of Aprepitant can be decreased when combined with Phenytoin.
Memantine Memantine The metabolism of Phenytoin can be decreased when combined with Memantine.
Tegaserod Tegaserod The metabolism of Phenytoin can be decreased when combined with Tegaserod.
Tadalafil Tadalafil The metabolism of Tadalafil can be increased when combined with Phenytoin.
Fosamprenavir Fosamprenavir The serum concentration of Phenytoin can be decreased when it is combined with Fosamprenavir.
Frovatriptan Frovatriptan The risk or severity of adverse effects can be increased when Phenytoin is combined with Frovatriptan.
Progesterone Progesterone The metabolism of Phenytoin can be increased when combined with Progesterone.
Apomorphine Injection Apomorphine Injection The metabolism of Apomorphine can be decreased when combined with Phenytoin.
Infliximab Injection Infliximab Injection The metabolism of Phenytoin can be increased when combined with Infliximab.
Oxandrolone Oxandrolone The metabolism of Phenytoin can be decreased when combined with Oxandrolone.
Protriptyline Protriptyline The risk or severity of adverse effects can be increased when Phenytoin is combined with Protriptyline.
Rifaximin Rifaximin The metabolism of Phenytoin can be increased when combined with Rifaximin.
Duloxetine Duloxetine The metabolism of Duloxetine can be increased when combined with Phenytoin.
Norethindrone Norethindrone The metabolism of Norethisterone can be increased when combined with Phenytoin.
Trospium Trospium Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Trospium.
Bosentan Bosentan The metabolism of Bosentan can be decreased when combined with Phenytoin.
Cinacalcet Cinacalcet The metabolism of Phenytoin can be decreased when combined with Cinacalcet.
Erlotinib Erlotinib The metabolism of Erlotinib can be increased when combined with Phenytoin.
Eszopiclone Eszopiclone The risk or severity of CNS depression can be increased when Phenytoin is combined with Eszopiclone.
Ganciclovir Ganciclovir The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Ganciclovir.
Solifenacin Solifenacin Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Solifenacin.
Valganciclovir Valganciclovir The therapeutic efficacy of Phenytoin can be decreased when used in combination with Valganciclovir.
Voriconazole Voriconazole The serum concentration of Phenytoin can be decreased when it is combined with Voriconazole.
Dextroamphetamine Dextroamphetamine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Amphetamine.
Peginterferon Alfa-2b (PEG-Intron) Peginterferon Alfa-2b (PEG-Intron) The metabolism of Phenytoin 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 Phenytoin.
Ibandronate Ibandronate The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Ibandronate.
Isocarboxazid Isocarboxazid The risk or severity of adverse effects can be increased when Phenytoin is combined with Isocarboxazid.
Ramelteon Ramelteon The metabolism of Ramelteon can be decreased when combined with Phenytoin.
Darifenacin Darifenacin The metabolism of Darifenacin can be decreased when combined with Phenytoin.
Fentanyl Fentanyl The risk or severity of adverse effects can be increased when Phenytoin is combined with Fentanyl.
Deferasirox Deferasirox The serum concentration of Deferasirox can be decreased when it is combined with Phenytoin.
Tipranavir Tipranavir The serum concentration of Tipranavir can be decreased when it is combined with Phenytoin.
Felbamate Felbamate The serum concentration of Phenytoin can be increased when it is combined with Felbamate.
Ranolazine Ranolazine The metabolism of Phenytoin can be increased when combined with Ranolazine.
Abatacept Injection Abatacept Injection The metabolism of Phenytoin can be increased when combined with Abatacept.
Rasagiline Rasagiline The risk or severity of adverse effects can be increased when Phenytoin is combined with Rasagiline.
Imatinib Imatinib The metabolism of Imatinib can be increased when combined with Phenytoin.
Sitagliptin Sitagliptin The metabolism of Phenytoin can be decreased when combined with Sitagliptin.
Gefitinib Gefitinib The metabolism of Gefitinib can be increased when combined with Phenytoin.
Paliperidone Paliperidone The risk or severity of adverse effects can be increased when Phenytoin is combined with Paliperidone.
Exemestane Exemestane The metabolism of Exemestane can be increased when combined with Phenytoin.
Bortezomib Bortezomib The metabolism of Bortezomib can be increased when combined with Phenytoin.
Fulvestrant Injection Fulvestrant Injection The metabolism of Fulvestrant can be increased when combined with Phenytoin.
Oxaliplatin Injection Oxaliplatin Injection Oxaliplatin can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Posaconazole Posaconazole The serum concentration of Phenytoin can be decreased when it is combined with Posaconazole.
Primaquine Primaquine The metabolism of Phenytoin can be decreased when combined with Primaquine.
Bismuth Subsalicylate Bismuth Subsalicylate The protein binding of Phenytoin can be decreased when combined with Bismuth subsalicylate.
Darunavir Darunavir The serum concentration of Phenytoin can be decreased when it is combined with Darunavir.
Dimenhydrinate Dimenhydrinate The risk or severity of adverse effects can be increased when Phenytoin is combined with Dimenhydrinate.
Lisdexamfetamine Lisdexamfetamine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Lisdexamfetamine.
Nabilone Nabilone Nabilone may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.
Retapamulin Retapamulin The metabolism of Retapamulin can be increased when combined with Phenytoin.
Sorafenib Sorafenib The metabolism of Phenytoin can be decreased when combined with Sorafenib.
Sunitinib Sunitinib The metabolism of Sunitinib can be increased when combined with Phenytoin.
Dronabinol Dronabinol Dronabinol may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.
Lapatinib Lapatinib The metabolism of Lapatinib can be increased when combined with Phenytoin.
Levocetirizine Levocetirizine The risk or severity of adverse effects can be increased when Phenytoin is combined with Levocetirizine.
Dasatinib Dasatinib The metabolism of Dasatinib can be increased when combined with Phenytoin.
Mexiletine Mexiletine The serum concentration of Mexiletine can be decreased when it is combined with Phenytoin.
Armodafinil Armodafinil The metabolism of Phenytoin can be decreased when combined with Armodafinil.
Ivermectin Ivermectin The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Ivermectin.
Temsirolimus Temsirolimus The metabolism of Temsirolimus can be increased when combined with Phenytoin.
Antipyrine-Benzocaine Otic Antipyrine-Benzocaine Otic The risk or severity of methemoglobinemia can be increased when Phenytoin is combined with Benzocaine.
Maraviroc Maraviroc The metabolism of Maraviroc can be increased when combined with Phenytoin.
Nilotinib Nilotinib The metabolism of Phenytoin can be decreased when combined with Nilotinib.
Raltegravir Raltegravir The metabolism of Raltegravir can be increased when combined with Phenytoin.
Bexarotene Bexarotene The metabolism of Bexarotene can be decreased when combined with Phenytoin.
Budesonide Budesonide The serum concentration of Phenytoin can be decreased when it is combined with Budesonide.
Chloramphenicol Injection Chloramphenicol Injection The serum concentration of Phenytoin can be increased when it is combined with Chloramphenicol.
OnabotulinumtoxinA Injection OnabotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Botulinum toxin type A is combined with Phenytoin.
RimabotulinumtoxinB Injection RimabotulinumtoxinB Injection The risk or severity of adverse effects can be increased when Botulinum Toxin Type B is combined with Phenytoin.
Etravirine Etravirine The serum concentration of Etravirine can be decreased when it is combined with Phenytoin.
Mitoxantrone Injection Mitoxantrone Injection The metabolism of Phenytoin can be increased when combined with Mitoxantrone.
Desvenlafaxine Desvenlafaxine The risk or severity of adverse effects can be increased when Phenytoin is combined with Desvenlafaxine.
Cevimeline Cevimeline The metabolism of Phenytoin can be decreased when combined with Cevimeline.
Nebivolol Nebivolol The metabolism of Nebivolol can be decreased when combined with Phenytoin.
Tretinoin Tretinoin The metabolism of Tretinoin can be decreased when combined with Phenytoin.
Leucovorin Injection Leucovorin Injection The serum concentration of Phenytoin can be decreased when it is combined with Leucovorin.
Pilocarpine Pilocarpine The metabolism of Phenytoin can be decreased when combined with Pilocarpine.
Flecainide Flecainide The metabolism of Phenytoin can be decreased when combined with Flecainide.
Certolizumab Injection Certolizumab Injection The metabolism of Phenytoin can be increased when combined with Certolizumab pegol.
Ixabepilone Injection Ixabepilone Injection The metabolism of Ixabepilone can be increased when combined with Phenytoin.
Irinotecan Injection Irinotecan Injection The metabolism of Irinotecan can be increased when combined with Phenytoin.
Levoleucovorin Injection Levoleucovorin Injection The serum concentration of Phenytoin can be decreased when it is combined with Levoleucovorin.
Daptomycin Injection Daptomycin Injection The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Daptomycin is combined with Phenytoin.
Praziquantel Praziquantel The metabolism of Praziquantel can be increased when combined with Phenytoin.
Mitotane Mitotane The therapeutic efficacy of Phenytoin can be decreased when used in combination with Mitotane.
Rufinamide Rufinamide The serum concentration of Phenytoin can be increased when it is combined with Rufinamide.
Midazolam Midazolam The risk or severity of adverse effects can be increased when Phenytoin is combined with Midazolam.
Naltrexone Injection Naltrexone Injection The metabolism of Naltrexone can be increased when combined with Phenytoin.
Eltrombopag Eltrombopag The metabolism of Phenytoin can be decreased when combined with Eltrombopag.
Milnacipran Milnacipran The metabolism of Milnacipran can be increased when combined with Phenytoin.
Dexlansoprazole Dexlansoprazole The metabolism of Phenytoin can be decreased when combined with Dexlansoprazole.
Sodium Phosphate Sodium Phosphate The therapeutic efficacy of Phenytoin can be decreased when used in combination with Sodium phosphate, monobasic.
Fesoterodine Fesoterodine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Fesoterodine.
Betaxolol Betaxolol The metabolism of Phenytoin can be decreased when combined with Betaxolol.
Iloperidone Iloperidone The metabolism of Iloperidone can be increased when combined with Phenytoin.
Prasugrel Prasugrel The metabolism of Prasugrel can be decreased when combined with Phenytoin.
Lacosamide Lacosamide The serum concentration of Lacosamide can be decreased when it is combined with Phenytoin.
Everolimus Everolimus The metabolism of Everolimus can be increased when combined with Phenytoin.
Tolvaptan (low blood sodium) Tolvaptan (low blood sodium) The metabolism of Tolvaptan can be increased when combined with Phenytoin.
Dronedarone Dronedarone The metabolism of Dronedarone can be increased when combined with Phenytoin.
AbobotulinumtoxinA Injection AbobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Botulinum toxin type A is combined with Phenytoin.
Palonosetron Injection Palonosetron Injection The risk or severity of adverse effects can be increased when Phenytoin is combined with Palonosetron.
Saxagliptin Saxagliptin The metabolism of Saxagliptin can be increased when combined with Phenytoin.
Romidepsin Injection Romidepsin Injection The metabolism of Romidepsin can be increased when combined with Phenytoin.
Tapentadol Tapentadol Tapentadol may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.
Topotecan Topotecan Phenytoin may increase the excretion rate of Topotecan which could result in a lower serum level and potentially a reduction in efficacy.
Golimumab Injection Golimumab Injection The metabolism of Phenytoin can be increased when combined with Golimumab.
Pazopanib Pazopanib The metabolism of Phenytoin can be decreased when combined with Pazopanib.
Asenapine Asenapine The risk or severity of adverse effects can be increased when Phenytoin is combined with Asenapine.
Vigabatrin Vigabatrin The serum concentration of Phenytoin can be decreased when it is combined with Vigabatrin.
Pitavastatin Pitavastatin The metabolism of Phenytoin can be decreased when combined with Pitavastatin.
Albendazole Albendazole The serum concentration of the active metabolites of Albendazole can be reduced when Albendazole is used in combination with Phenytoin resulting in a loss in efficacy.
Ulipristal Ulipristal The metabolism of Ulipristal can be increased when combined with Phenytoin.
Levonorgestrel Levonorgestrel The metabolism of Levonorgestrel can be increased when combined with Phenytoin.
Oxymorphone Oxymorphone The risk or severity of adverse effects can be increased when Phenytoin is combined with Oxymorphone.
Tocilizumab Injection Tocilizumab Injection The metabolism of Phenytoin can be increased when combined with Tocilizumab.
Fingolimod Fingolimod The metabolism of Fingolimod can be decreased when combined with Phenytoin.
IncobotulinumtoxinA Injection IncobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Botulinum toxin type A is combined with Phenytoin.
Cabazitaxel Injection Cabazitaxel Injection The metabolism of Cabazitaxel can be decreased when combined with Phenytoin.
Lurasidone Lurasidone The risk or severity of adverse effects can be increased when Phenytoin is combined with Lurasidone.
Acetaminophen Injection Acetaminophen Injection Acetaminophen may increase the hepatotoxic activities of Phenytoin.
Vilazodone Vilazodone The metabolism of Vilazodone can be increased when combined with Phenytoin.
Denileukin Diftitox Injection Denileukin Diftitox Injection The metabolism of Phenytoin can be decreased when combined with Aldesleukin.
Busulfan Injection Busulfan Injection The serum concentration of Busulfan can be decreased when it is combined with Phenytoin.
Roflumilast Roflumilast The metabolism of Roflumilast can be increased when combined with Phenytoin.
Linagliptin Linagliptin The metabolism of Linagliptin can be increased when combined with Phenytoin.
Rilpivirine Rilpivirine The serum concentration of Rilpivirine can be decreased when it is combined with Phenytoin.
Telaprevir Telaprevir The metabolism of Phenytoin can be decreased when combined with Glecaprevir.
Cyclophosphamide Injection Cyclophosphamide Injection The metabolism of Cyclophosphamide can be decreased when combined with Phenytoin.
Abiraterone Abiraterone The metabolism of Abiraterone can be increased when combined with Phenytoin.
Rivaroxaban Rivaroxaban The metabolism of Rivaroxaban can be increased when combined with Phenytoin.
Ticagrelor Ticagrelor The metabolism of Phenytoin can be decreased when combined with Ticagrelor.
Brentuximab Vedotin Injection Brentuximab Vedotin Injection The metabolism of Brentuximab vedotin can be increased when combined with Phenytoin.
Ruxolitinib Ruxolitinib The metabolism of Ruxolitinib can be increased when combined with Phenytoin.
Vandetanib Vandetanib The metabolism of Vandetanib can be increased when combined with Phenytoin.
Clobazam Clobazam The metabolism of Clobazam can be decreased when combined with Phenytoin.
Vemurafenib Vemurafenib The metabolism of Phenytoin can be decreased when combined with Vemurafenib.
Vismodegib Vismodegib The metabolism of Phenytoin can be decreased when combined with Vismodegib.
Ivacaftor Ivacaftor The serum concentration of Ivacaftor can be decreased when it is combined with Phenytoin.
Deferiprone Deferiprone The serum concentration of Deferiprone can be increased when it is combined with Phenytoin.
Axitinib Axitinib The metabolism of Axitinib can be increased when combined with Phenytoin.
Crizotinib Crizotinib The metabolism of Phenytoin can be increased when combined with Crizotinib.
Cabergoline Cabergoline The metabolism of Phenytoin can be increased when combined with Cabergoline.
Naloxone Injection Naloxone Injection The metabolism of Naloxone can be increased when combined with Phenytoin.
Ambrisentan Ambrisentan The metabolism of Ambrisentan can be increased when combined with Phenytoin.
Ezogabine Ezogabine The risk or severity of adverse effects can be increased when Phenytoin is combined with Tiagabine.
Iloprost Iloprost The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Iloprost.
Enzalutamide Enzalutamide The metabolism of Phenytoin can be decreased when combined with Enzalutamide.
Asparaginase Erwinia Chrysanthemi Injection Asparaginase Erwinia Chrysanthemi Injection The therapeutic efficacy of Phenytoin can be increased when used in combination with Asparaginase Erwinia chrysanthemi.
Mirabegron Mirabegron The metabolism of Phenytoin can be decreased when combined with Mirabegron.
Regorafenib Regorafenib The metabolism of Phenytoin can be decreased when combined with Regorafenib.
Bosutinib Bosutinib The metabolism of Phenytoin can be decreased when combined with Bosutinib.
Corticotropin, Repository Injection Corticotropin, Repository Injection The serum concentration of Corticotropin can be decreased when it is combined with Phenytoin.
Teriflunomide Teriflunomide The metabolism of Phenytoin can be decreased when combined with Teriflunomide.
Cabozantinib (thyroid cancer) Cabozantinib (thyroid cancer) The metabolism of Cabozantinib can be increased when combined with Phenytoin.
Alogliptin Alogliptin The metabolism of Alogliptin can be decreased when combined with Phenytoin.
Ponatinib Ponatinib The metabolism of Ponatinib can be decreased when combined with Phenytoin.
Pomalidomide Pomalidomide The metabolism of Pomalidomide can be increased when combined with Phenytoin.
Ado-trastuzumab Emtansine Injection Ado-trastuzumab Emtansine Injection The metabolism of Trastuzumab emtansine can be increased when combined with Phenytoin.
Apixaban Apixaban The metabolism of Apixaban can be decreased when combined with Phenytoin.
Canagliflozin Canagliflozin The serum concentration of Canagliflozin can be decreased when it is combined with Phenytoin.
Methazolamide Methazolamide The risk or severity of osteomalacia can be increased when Methazolamide is combined with Phenytoin.
Dabrafenib Dabrafenib The serum concentration of Phenytoin can be decreased when it is combined with Dabrafenib.
Ospemifene Ospemifene The metabolism of Ospemifene can be decreased when combined with Phenytoin.
Trametinib Trametinib The metabolism of Phenytoin can be decreased when combined with Trametinib.
Dolutegravir Dolutegravir The metabolism of Dolutegravir can be increased when combined with Phenytoin.
Levomilnacipran Levomilnacipran The metabolism of Phenytoin can be increased when combined with Levomilnacipran.
Vortioxetine Vortioxetine The metabolism of Vortioxetine can be increased when combined with Phenytoin.
Perampanel Perampanel The metabolism of Perampanel can be increased when combined with Phenytoin.
Ibrutinib Ibrutinib The metabolism of Ibrutinib can be increased when combined with Phenytoin.
Lomitapide Lomitapide The metabolism of Lomitapide can be increased when combined with Phenytoin.
Ketorolac Injection Ketorolac Injection The serum concentration of Phenytoin can be increased when it is combined with Ketorolac.
Dapagliflozin Dapagliflozin The metabolism of Dapagliflozin can be decreased when combined with Phenytoin.
Apremilast Apremilast The metabolism of Phenytoin can be increased when combined with Apremilast.
Ceritinib Ceritinib The metabolism of Ceritinib can be increased when combined with Phenytoin.
Siltuximab Injection Siltuximab Injection The metabolism of Phenytoin can be increased when combined with Siltuximab.
Eslicarbazepine Eslicarbazepine The serum concentration of Eslicarbazepine can be decreased when it is combined with Phenytoin.
Belinostat Injection Belinostat Injection The metabolism of Belinostat can be increased when combined with Phenytoin.
Idelalisib Idelalisib The metabolism of Idelalisib can be increased when combined with Phenytoin.
Testosterone Injection Testosterone Injection The metabolism of Phenytoin can be decreased when combined with Testosterone.
Oritavancin Injection Oritavancin Injection The metabolism of Phenytoin can be decreased when combined with Oritavancin.
Vorapaxar Vorapaxar The metabolism of Vorapaxar can be increased when combined with Phenytoin.
Hydrocodone Hydrocodone The metabolism of Hydrocodone can be increased when combined with Phenytoin.
Suvorexant Suvorexant Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Suvorexant.
Olaparib Olaparib The metabolism of Olaparib can be increased when combined with Phenytoin.
Methamphetamine Methamphetamine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Metamfetamine.
Tasimelteon Tasimelteon The metabolism of Tasimelteon can be increased when combined with Phenytoin.
Riociguat Riociguat The metabolism of Riociguat can be decreased when combined with Phenytoin.
Nintedanib Nintedanib The metabolism of Nintedanib can be increased when combined with Phenytoin.
Secukinumab Injection Secukinumab Injection The metabolism of Phenytoin can be increased when combined with Secukinumab.
Risperidone Injection Risperidone Injection The metabolism of Risperidone can be increased when combined with Phenytoin.
Palbociclib Palbociclib The metabolism of Palbociclib can be increased when combined with Phenytoin.
Lenvatinib Lenvatinib The metabolism of Phenytoin can be decreased when combined with Lenvatinib.
Naloxegol Naloxegol The metabolism of Phenytoin can be decreased when combined with Naloxegol.
Panobinostat Panobinostat The metabolism of Phenytoin can be decreased when combined with Panobinostat.
Haloperidol Injection Haloperidol Injection The risk or severity of CNS depression can be increased when Phenytoin is combined with Haloperidol.
Sonidegib Sonidegib The metabolism of Sonidegib can be increased when combined with Phenytoin.
Flibanserin Flibanserin The risk or severity of adverse effects can be increased when Phenytoin is combined with Flibanserin.
Rolapitant Rolapitant The metabolism of Phenytoin can be decreased when combined with Rolapitant.
Prednisolone Prednisolone The serum concentration of Phenytoin can be decreased when it is combined with Prednisolone.
Daclatasvir Daclatasvir The metabolism of Daclatasvir can be increased when combined with Phenytoin.
Brexpiprazole Brexpiprazole The metabolism of Brexpiprazole can be increased when combined with Phenytoin.
Ziprasidone Injection Ziprasidone Injection The risk or severity of adverse effects can be increased when Phenytoin is combined with Ziprasidone.
Cariprazine Cariprazine The risk or severity of adverse effects can be increased when Phenytoin is combined with Cariprazine.
Cobimetinib Cobimetinib The metabolism of Cobimetinib can be increased when combined with Phenytoin.
Trabectedin Injection Trabectedin Injection The metabolism of Trabectedin can be decreased when combined with Phenytoin.
Osimertinib Osimertinib The metabolism of Osimertinib can be increased when combined with Phenytoin.
Alectinib Alectinib The metabolism of Alectinib can be increased when combined with Phenytoin.
Ixazomib Ixazomib The metabolism of Ixazomib can be increased when combined with Phenytoin.
Rifapentine Rifapentine The metabolism of Phenytoin can be increased when combined with Rifapentine.
Lesinurad Lesinurad The metabolism of Phenytoin can be decreased when combined with Lesinurad.
Amphotericin B Liposomal Injection Amphotericin B Liposomal Injection The therapeutic efficacy of Phenytoin can be decreased when used in combination with Amphotericin B.
Dexamethasone Injection Dexamethasone Injection The serum concentration of Dexamethasone can be decreased when it is combined with Phenytoin.
Brivaracetam Injection Brivaracetam Injection The metabolism of Brivaracetam can be decreased when combined with Phenytoin.
Venetoclax Venetoclax The metabolism of Venetoclax can be increased when combined with Phenytoin.
Cobicistat Cobicistat The metabolism of Phenytoin can be decreased when combined with Cobicistat.
Selexipag Selexipag The metabolism of Phenytoin can be decreased when combined with Selexipag.
Pimavanserin Pimavanserin The risk or severity of adverse effects can be increased when Phenytoin is combined with Pimavanserin.
Diphenhydramine Injection Diphenhydramine Injection The metabolism of Phenytoin can be decreased when combined with Diphenhydramine.
Calcifediol Calcifediol The serum concentration of Calcifediol can be decreased when it is combined with Phenytoin.
Ergocalciferol Ergocalciferol The serum concentration of Ergocalciferol can be decreased when it is combined with Phenytoin.
Doxercalciferol Doxercalciferol The serum concentration of Doxercalciferol can be decreased when it is combined with Phenytoin.
Furosemide Injection Furosemide Injection Phenytoin may decrease the diuretic activities of Furosemide.
Rucaparib Rucaparib The metabolism of Phenytoin can be decreased when combined with Rucaparib.
Ribociclib Ribociclib The metabolism of Ribociclib can be increased when combined with Phenytoin.
Brigatinib Brigatinib The metabolism of Brigatinib can be decreased when combined with Phenytoin.
Doxepin (Insomnia) Doxepin (Insomnia) The metabolism of Doxepin can be decreased when combined with Phenytoin.
Deutetrabenazine Deutetrabenazine The metabolism of Deutetrabenazine can be increased when combined with Phenytoin.
Valbenazine Valbenazine The metabolism of Valbenazine can be increased when combined with Phenytoin.
Deflazacort Deflazacort The serum concentration of Deflazacort can be decreased when it is combined with Phenytoin.
Safinamide Safinamide The metabolism of Phenytoin can be decreased when combined with Safinamide.
Midostaurin Midostaurin The metabolism of Phenytoin can be decreased when combined with Midostaurin.
Neratinib Neratinib The metabolism of Neratinib can be increased when combined with Phenytoin.
Enasidenib Enasidenib The metabolism of Phenytoin can be decreased when combined with Enasidenib.
Aprepitant/Fosaprepitant Injection Aprepitant/Fosaprepitant Injection The metabolism of Fosaprepitant can be increased when combined with Phenytoin.
Copanlisib Injection Copanlisib Injection The metabolism of Copanlisib can be increased when combined with Phenytoin.
Delafloxacin Delafloxacin The metabolism of Phenytoin can be increased when combined with Delafloxacin.
Abemaciclib Abemaciclib The metabolism of Abemaciclib can be increased when combined with Phenytoin.
Acalabrutinib Acalabrutinib The metabolism of Phenytoin can be increased when combined with Acalabrutinib.
Letermovir Letermovir The metabolism of Phenytoin can be increased when combined with Letermovir.
Tetrabenazine Tetrabenazine The metabolism of Tetrabenazine can be decreased when combined with Phenytoin.
Ertugliflozin Ertugliflozin The metabolism of Ertugliflozin can be decreased when combined with Phenytoin.
Buprenorphine Injection Buprenorphine Injection Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Buprenorphine.
Apalutamide Apalutamide The serum concentration of Phenytoin can be increased when it is combined with Apalutamide.
Penicillamine Penicillamine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Penicillamine.
Fostamatinib Fostamatinib The metabolism of Fostamatinib can be decreased when combined with Phenytoin.
Avatrombopag Avatrombopag The metabolism of Phenytoin can be increased when combined with Avatrombopag.
Baricitinib Baricitinib The metabolism of Baricitinib can be increased when combined with Phenytoin.
Lofexidine Lofexidine The therapeutic efficacy of Phenytoin can be increased when used in combination with Lofexidine.
Eliglustat Eliglustat The metabolism of Phenytoin can be decreased when combined with Eliglustat.
Encorafenib Encorafenib The metabolism of Encorafenib can be decreased when combined with Phenytoin.
Binimetinib Binimetinib The metabolism of Binimetinib can be increased when combined with Phenytoin.
Ivosidenib Ivosidenib The metabolism of Phenytoin can be increased when combined with Ivosidenib.
Elagolix Elagolix The metabolism of Phenytoin can be decreased when combined with Elagolix.
Doravirine Doravirine The metabolism of Doravirine can be increased when combined with Phenytoin.
Tafenoquine Tafenoquine The metabolism of Tafenoquine can be decreased when combined with Phenytoin.
Cannabidiol Cannabidiol The risk or severity of adverse effects can be increased when Cannabidiol is combined with Phenytoin.
Dacomitinib Dacomitinib The metabolism of Dacomitinib can be increased when combined with Phenytoin.
Duvelisib Duvelisib The metabolism of Duvelisib can be increased when combined with Phenytoin.
Stiripentol Stiripentol The serum concentration of Phenytoin can be increased when it is combined with Stiripentol.
Gilteritinib Gilteritinib The metabolism of Gilteritinib can be increased when combined with Phenytoin.
Glasdegib Glasdegib The metabolism of Glasdegib can be decreased when combined with Phenytoin.
Lorlatinib Lorlatinib The metabolism of Phenytoin can be decreased when combined with Lorlatinib.
Paclitaxel (with albumin) Injection Paclitaxel (with albumin) Injection The serum concentration of Phenytoin can be decreased when it is combined with Paclitaxel.
Rifamycin Rifamycin The metabolism of Phenytoin can be decreased when combined with Rifamycin.
Prucalopride Prucalopride The metabolism of Prucalopride can be increased when combined with Phenytoin.
Magnesium Citrate Magnesium Citrate Magnesium citrate can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Emapalumab-lzsg Injection Emapalumab-lzsg Injection The metabolism of Phenytoin can be increased when combined with Emapalumab.
Siponimod Siponimod The therapeutic efficacy of Siponimod can be decreased when used in combination with Phenytoin.
Erdafitinib Erdafitinib The metabolism of Erdafitinib can be increased when combined with Phenytoin.
Esomeprazole Injection Esomeprazole Injection The serum concentration of Phenytoin can be increased when it is combined with Esomeprazole.
Alpelisib Alpelisib The serum concentration of Alpelisib can be decreased when it is combined with Phenytoin.
Brexanolone Injection Brexanolone Injection The risk or severity of adverse effects can be increased when Phenytoin is combined with Brexanolone.
Cladribine Cladribine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Cladribine is combined with Phenytoin.
Polatuzumab vedotin-piiq Injection Polatuzumab vedotin-piiq Injection The risk or severity of adverse effects can be decreased when Phenytoin is combined with Polatuzumab vedotin.
Solriamfetol Solriamfetol The risk or severity of adverse effects can be increased when Phenytoin is combined with Solriamfetol.
Darolutamide Darolutamide The serum concentration of Phenytoin can be decreased when it is combined with Darolutamide.
Triclabendazole Triclabendazole The metabolism of Phenytoin can be decreased when combined with Triclabendazole.
Entrectinib Entrectinib The metabolism of Entrectinib can be increased when combined with Phenytoin.
Pexidartinib Pexidartinib The metabolism of Pexidartinib can be increased when combined with Phenytoin.
Upadacitinib Upadacitinib The metabolism of Upadacitinib can be increased when combined with Phenytoin.
Istradefylline Istradefylline The metabolism of Phenytoin can be decreased when combined with Istradefylline.
Pitolisant Pitolisant The metabolism of Pitolisant can be increased when combined with Phenytoin.
Fedratinib Fedratinib The metabolism of Fedratinib can be increased when combined with Phenytoin.
Lefamulin Lefamulin The metabolism of Lefamulin can be increased when combined with Phenytoin.
Fosphenytoin Injection Fosphenytoin Injection The metabolism of Fosphenytoin can be increased when combined with Phenytoin.
Zanubrutinib Zanubrutinib The metabolism of Zanubrutinib can be increased when combined with Phenytoin.
Voxelotor Voxelotor The serum concentration of Voxelotor can be decreased when it is combined with Phenytoin.
Avapritinib Avapritinib The metabolism of Avapritinib can be decreased when combined with Phenytoin.
Lumateperone Lumateperone The serum concentration of Lumateperone can be decreased when it is combined with Phenytoin.
Lasmiditan Lasmiditan The risk or severity of adverse effects can be increased when Phenytoin is combined with Lasmiditan.
Ubrogepant Ubrogepant The serum concentration of Ubrogepant can be decreased when it is combined with Phenytoin.
Tazemetostat Tazemetostat The metabolism of Tazemetostat can be increased when combined with Phenytoin.
Cenobamate Cenobamate The serum concentration of Cenobamate can be increased when it is combined with Phenytoin.
Pemigatinib Pemigatinib The metabolism of Pemigatinib can be increased when combined with Phenytoin.
Ozanimod Ozanimod The metabolism of Ozanimod can be decreased when combined with Phenytoin.
Selumetinib Selumetinib The serum concentration of Selumetinib can be decreased when it is combined with Phenytoin.
Rimegepant Rimegepant The metabolism of Rimegepant can be increased when combined with Phenytoin.
Tucatinib Tucatinib The metabolism of Tucatinib can be increased when combined with Phenytoin.
Sacituzumab govitecan-hziy Injection Sacituzumab govitecan-hziy Injection The serum concentration of Sacituzumab govitecan can be decreased when it is combined with Phenytoin.
Ripretinib Ripretinib The serum concentration of Ripretinib can be decreased when it is combined with Phenytoin.
Selpercatinib Selpercatinib The serum concentration of Phenytoin can be decreased when it is combined with Selpercatinib.
Capmatinib Capmatinib The serum concentration of Capmatinib can be decreased when it is combined with Phenytoin.
Lemborexant Lemborexant The serum concentration of Lemborexant can be decreased when it is combined with Phenytoin.
Daratumumab and Hyaluronidase-fihj Injection Daratumumab and Hyaluronidase-fihj Injection The therapeutic efficacy of Phenytoin can be decreased when used in combination with Hyaluronidase.
Fenfluramine Fenfluramine The serum concentration of Fenfluramine can be decreased when it is combined with Phenytoin.
Fostemsavir Fostemsavir The serum concentration of Fostemsavir can be decreased when it is combined with Phenytoin.
Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf Injection Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf Injection The therapeutic efficacy of Phenytoin can be decreased when used in combination with Hyaluronidase.
Lurbinectedin Injection Lurbinectedin Injection The serum concentration of Lurbinectedin can be decreased when it is combined with Phenytoin.
Pralsetinib Pralsetinib The serum concentration of Phenytoin can be decreased when it is combined with Pralsetinib.
Opicapone Opicapone The metabolism of Phenytoin can be decreased when combined with Opicapone.
Satralizumab-mwge Injection Satralizumab-mwge Injection The serum concentration of Phenytoin can be decreased when it is combined with Satralizumab.
Relugolix Relugolix The serum concentration of Relugolix can be decreased when it is combined with Phenytoin.
Progestin-Only (drospirenone) Oral Contraceptives Progestin-Only (drospirenone) Oral Contraceptives The metabolism of Drospirenone can be increased when combined with Phenytoin.
Viloxazine Viloxazine The risk or severity of adverse effects can be increased when Phenytoin is combined with Viloxazine.
Theophylline Theophylline The serum concentration of Theophylline can be decreased when it is combined with Phenytoin.
Fenoprofen Fenoprofen The serum concentration of Phenytoin can be increased when it is combined with Fenoprofen.
Indomethacin Indomethacin The serum concentration of Phenytoin can be increased when it is combined with Indomethacin.
Mefenamic Acid Mefenamic Acid The serum concentration of Phenytoin can be increased when it is combined with Mefenamic acid.
Naproxen Naproxen The serum concentration of Phenytoin can be increased when it is combined with Naproxen.
Tolmetin Tolmetin The serum concentration of Phenytoin can be increased when it is combined with Tolmetin.
Sulindac Sulindac The serum concentration of Phenytoin can be increased when it is combined with Sulindac.
Trazodone Trazodone The serum concentration of Phenytoin can be increased when it is combined with Trazodone.
Isotretinoin Isotretinoin The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Isotretinoin.
Sucralfate Sucralfate Sucralfate can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Hydroxyurea Hydroxyurea The metabolism of Phenytoin can be decreased when combined with Hydroxyurea.
Floxuridine Floxuridine The serum concentration of Phenytoin can be increased when it is combined with Floxuridine.
Metaxalone Metaxalone The risk or severity of adverse effects can be increased when Phenytoin is combined with Metaxalone.
Methotrexate Injection Methotrexate Injection The serum concentration of Methotrexate can be decreased when it is combined with Phenytoin.
Levorphanol Levorphanol The risk or severity of adverse effects can be increased when Phenytoin is combined with Levorphanol.
Primidone Primidone The metabolism of Primidone can be increased when combined with Phenytoin.
Methsuximide Methsuximide The serum concentration of Phenytoin can be increased when it is combined with Methsuximide.
Diethylpropion Diethylpropion The therapeutic efficacy of Phenytoin can be decreased when used in combination with Diethylpropion.
Chlorpromazine Chlorpromazine The metabolism of Chlorpromazine can be increased when combined with Phenytoin.
Diazepam Diazepam The serum concentration of Diazepam can be decreased when it is combined with Phenytoin.
Oxazepam Oxazepam The metabolism of Oxazepam can be decreased when combined with Phenytoin.
Flurazepam Flurazepam The risk or severity of adverse effects can be increased when Phenytoin is combined with Flurazepam.
Clorazepate Clorazepate The risk or severity of adverse effects can be increased when Phenytoin is combined with Clorazepic acid.
Lorazepam Lorazepam The metabolism of Lorazepam can be increased when combined with Phenytoin.
Carmustine Carmustine The serum concentration of Phenytoin can be decreased when it is combined with Carmustine.
Codeine Codeine The risk or severity of adverse effects can be increased when Phenytoin is combined with Codeine.
Meprobamate Meprobamate The risk or severity of adverse effects can be increased when Phenytoin is combined with Meprobamate.
Chlordiazepoxide Chlordiazepoxide The serum concentration of Chlordiazepoxide can be increased when it is combined with Phenytoin.
Bromocriptine Bromocriptine The risk or severity of adverse effects can be increased when Phenytoin is combined with Bromocriptine.
Tranylcypromine Tranylcypromine The metabolism of Phenytoin can be decreased when combined with Tranylcypromine.
Phenelzine Phenelzine The metabolism of Phenytoin can be decreased when combined with Phenelzine.
Procarbazine Procarbazine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Procarbazine.
Ergoloid Mesylates Ergoloid Mesylates The risk or severity of adverse effects can be increased when Phenytoin is combined with Ergoloid mesylate.
Minocycline Minocycline Minocycline may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.
Prochlorperazine Prochlorperazine The metabolism of Prochlorperazine can be increased when combined with Phenytoin.
Thioridazine Thioridazine The serum concentration of Thioridazine can be increased when it is combined with Phenytoin.
Trifluoperazine Trifluoperazine The serum concentration of Phenytoin can be increased when it is combined with Trifluoperazine.
Bleomycin Bleomycin The serum concentration of Phenytoin can be decreased when it is combined with Bleomycin.
Dapsone Dapsone The risk or severity of methemoglobinemia can be increased when Dapsone is combined with Phenytoin.
Sulfadiazine Sulfadiazine The serum concentration of Phenytoin can be increased when it is combined with Sulfadiazine.
Oxycodone Oxycodone The metabolism of Oxycodone can be increased when combined with Phenytoin.
Methadone Methadone The risk or severity of adverse effects can be increased when Methadone is combined with Phenytoin.
Oxybutynin Oxybutynin The metabolism of Oxybutynin can be decreased when combined with Phenytoin.
Benztropine Benztropine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Benzatropine.
Colestipol Colestipol Colestipol can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Maprotiline Maprotiline Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Maprotiline.
Ibuprofen Ibuprofen The serum concentration of Phenytoin can be increased when it is combined with Ibuprofen.
Trihexyphenidyl Trihexyphenidyl Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Trihexyphenidyl.
Orphenadrine Orphenadrine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine.
Perphenazine Perphenazine The serum concentration of Perphenazine can be increased when it is combined with Phenytoin.
Fluphenazine Fluphenazine The serum concentration of Phenytoin can be increased when it is combined with Fluphenazine.
Phentermine Phentermine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Phentermine.
Methylphenidate Methylphenidate The serum concentration of Phenytoin can be increased when it is combined with Methylphenidate.
Amoxapine Amoxapine The metabolism of Amoxapine can be decreased when combined with Phenytoin.
Sulfasalazine Sulfasalazine The serum concentration of Phenytoin can be increased when it is combined with Sulfasalazine.
Hydrocortisone Hydrocortisone The serum concentration of Hydrocortisone can be decreased when it is combined with Phenytoin.
Doxorubicin Doxorubicin The metabolism of Phenytoin can be increased when combined with Doxorubicin.
Cytarabine Cytarabine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Cytarabine.
Phenazopyridine Phenazopyridine The risk or severity of methemoglobinemia can be increased when Phenytoin is combined with Phenazopyridine.
Carbamazepine Carbamazepine The serum concentration of Carbamazepine can be decreased when it is combined with Phenytoin.
Molindone Molindone The risk or severity of adverse effects can be increased when Phenytoin is combined with Molindone.
Methyldopa Methyldopa The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Methyldopa.
Clonidine Clonidine The risk or severity of sedation can be increased when Clonidine is combined with Phenytoin.
Cimetidine Cimetidine The serum concentration of Phenytoin can be increased when it is combined with Cimetidine.
Warfarin Warfarin The metabolism of Warfarin can be increased when combined with Phenytoin.
Clonazepam Clonazepam The metabolism of Clonazepam can be increased when combined with Phenytoin.
Loperamide Loperamide The metabolism of Loperamide can be decreased when combined with Phenytoin.
Promethazine Promethazine The serum concentration of Phenytoin can be increased when it is combined with Promethazine.
Meclofenamate Meclofenamate The serum concentration of Phenytoin can be increased when it is combined with Meclofenamic acid.
Daunorubicin Daunorubicin The metabolism of Phenytoin can be increased when combined with Daunorubicin.
Nitrofurantoin Nitrofurantoin The risk or severity of methemoglobinemia can be increased when Phenytoin is combined with Nitrofurantoin.
Griseofulvin Griseofulvin The metabolism of Phenytoin can be increased when combined with Griseofulvin.
Digoxin Digoxin The serum concentration of Digoxin can be decreased when it is combined with Phenytoin.
Loxapine Loxapine The risk or severity of adverse effects can be increased when Phenytoin is combined with Loxapine.
Mebendazole Mebendazole The serum concentration of Mebendazole can be decreased when it is combined with Phenytoin.
Chloroquine Chloroquine The metabolism of Phenytoin can be decreased when combined with Chloroquine.
Quinine Quinine The serum concentration of Quinine can be decreased when it is combined with Phenytoin.
Ethosuximide Ethosuximide The serum concentration of Ethosuximide can be increased when it is combined with Phenytoin.
Calcitriol Calcitriol The serum concentration of Calcitriol can be decreased when it is combined with Phenytoin.
Sulfinpyrazone Sulfinpyrazone The metabolism of Phenytoin can be decreased when combined with Sulfinpyrazone.
Isosorbide Isosorbide The metabolism of Isosorbide can be increased when combined with Phenytoin.
Clindamycin Injection Clindamycin Injection The metabolism of Clindamycin can be increased when combined with Phenytoin.
Secobarbital Secobarbital The metabolism of Phenytoin can be increased when combined with Secobarbital.
Desipramine Desipramine The metabolism of Desipramine can be decreased when combined with Phenytoin.
Amitriptyline Amitriptyline The metabolism of Amitriptyline can be decreased when combined with Phenytoin.
Imipramine Imipramine The metabolism of Phenytoin can be decreased when combined with Imipramine.
Probenecid Probenecid The metabolism of Phenytoin can be decreased when combined with Probenecid.
Quinidine Quinidine The serum concentration of Quinidine can be decreased when it is combined with Phenytoin.
Procainamide Procainamide The metabolism of Procainamide can be decreased when combined with Phenytoin.
Isoniazid Isoniazid The serum concentration of Phenytoin can be increased when it is combined with Isoniazid.
Rifampin Rifampin The serum concentration of Phenytoin can be decreased when it is combined with Rifampicin.
Disopyramide Disopyramide The serum concentration of Disopyramide can be decreased when it is combined with Phenytoin.
Valproic Acid Valproic Acid The serum concentration of Phenytoin can be decreased when it is combined with Valproic acid.
Tamoxifen Tamoxifen The metabolism of Phenytoin can be decreased when combined with Tamoxifen.
Butabarbital Butabarbital The risk or severity of adverse effects can be increased when Butabarbital is combined with Phenytoin.
Levothyroxine Levothyroxine The metabolism of Levothyroxine can be decreased when combined with Phenytoin.
Liothyronine Liothyronine The metabolism of Liothyronine can be increased when combined with Phenytoin.
Methimazole Methimazole The metabolism of Phenytoin can be decreased when combined with Methimazole.
Propylthiouracil Propylthiouracil The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Propylthiouracil.
Chlorpropamide Chlorpropamide Chlorpropamide may decrease the hypoglycemic activities of Phenytoin.
Tolbutamide Tolbutamide The serum concentration of Phenytoin can be increased when it is combined with Tolbutamide.
Tolazamide Tolazamide The therapeutic efficacy of Phenytoin can be decreased when used in combination with Tolazamide.
Dextromethorphan Dextromethorphan The metabolism of Dextromethorphan can be decreased when combined with Phenytoin.
Cyclobenzaprine Cyclobenzaprine The risk or severity of CNS depression can be increased when Phenytoin is combined with Cyclobenzaprine.
Niacin Niacin The therapeutic efficacy of Phenytoin can be increased when used in combination with Niacin.
Baclofen Baclofen The risk or severity of adverse effects can be increased when Baclofen is combined with Phenytoin.
Doxylamine Doxylamine Doxylamine may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.
Cyproheptadine Cyproheptadine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Cyproheptadine.
Clemastine Clemastine The risk or severity of adverse effects can be increased when Phenytoin is combined with Clemastine.
Chlorpheniramine Chlorpheniramine The serum concentration of Chlorpheniramine can be increased when it is combined with Phenytoin.
Brompheniramine Brompheniramine The risk or severity of adverse effects can be increased when Phenytoin is combined with Dexbrompheniramine.
Meclizine Meclizine The risk or severity of adverse effects can be increased when Phenytoin is combined with Meclizine.
Dantrolene Dantrolene The risk or severity of adverse effects can be increased when Phenytoin is combined with Dantrolene.
Chlorzoxazone Chlorzoxazone The risk or severity of adverse effects can be increased when Phenytoin is combined with Chlorzoxazone.
Carisoprodol Carisoprodol The risk or severity of adverse effects can be increased when Carisoprodol is combined with Phenytoin.
Methocarbamol Methocarbamol The risk or severity of adverse effects can be increased when Phenytoin is combined with Methocarbamol.
Pyridoxine Pyridoxine The metabolism of Phenytoin can be increased when combined with Pyridoxine.
Folic Acid Folic Acid The serum concentration of Phenytoin can be decreased when it is combined with Folic acid.
Danazol Danazol The therapeutic efficacy of Phenytoin can be increased when used in combination with Danazol.
Disulfiram Disulfiram The serum concentration of Disulfiram can be increased when it is combined with Phenytoin.
Propranolol (Cardiovascular) Propranolol (Cardiovascular) The serum concentration of Propranolol can be decreased when it is combined with Phenytoin.
Minoxidil Minoxidil The metabolism of Minoxidil can be increased when combined with Phenytoin.
Pseudoephedrine Pseudoephedrine The therapeutic efficacy of Phenytoin can be decreased when used in combination with Pseudoephedrine.
Nortriptyline Nortriptyline The metabolism of Nortriptyline can be increased when combined with Phenytoin.
Spironolactone Spironolactone The metabolism of Phenytoin can be decreased when combined with Spironolactone.
Amphotericin B Injection Amphotericin B Injection The therapeutic efficacy of Phenytoin can be decreased when used in combination with Amphotericin B.
Mercaptopurine Mercaptopurine The serum concentration of Mercaptopurine can be decreased when it is combined with Phenytoin.
Nadolol Nadolol The metabolism of Nadolol can be decreased when combined with Phenytoin.
Butorphanol Injection Butorphanol Injection The risk or severity of adverse effects can be increased when Phenytoin is combined with Butorphanol.
Nalbuphine Injection Nalbuphine Injection The risk or severity of adverse effects can be increased when Phenytoin is combined with Nalbuphine.
Cholestyramine Resin Cholestyramine Resin Cholestyramine can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Allopurinol Allopurinol The metabolism of Phenytoin can be decreased when combined with Allopurinol.
Trimethobenzamide Trimethobenzamide The risk or severity of adverse effects can be increased when Phenytoin is combined with Trimethobenzamide.
Flavoxate Flavoxate Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Flavoxate.
Fluorouracil Injection Fluorouracil Injection The serum concentration of Phenytoin can be increased when it is combined with Fluorouracil.
Colchicine Colchicine The metabolism of Phenytoin can be decreased when combined with Colchicine.
Cefazolin Injection Cefazolin Injection The protein binding of Phenytoin can be decreased when combined with Cefazolin.
Cephalexin Cephalexin The metabolism of Cephalexin can be increased when combined with Phenytoin.
Acetazolamide Acetazolamide The risk or severity of osteomalacia can be increased when Acetazolamide is combined with Phenytoin.
Cefotaxime Injection Cefotaxime Injection The therapeutic efficacy of Phenytoin can be decreased when used in combination with Cefotaxime.
Ketoconazole Ketoconazole The serum concentration of Phenytoin can be increased when it is combined with Ketoconazole.
Pyrantel Pyrantel The therapeutic efficacy of Pyrantel can be decreased when used in combination with Phenytoin.
Thiotepa Injection Thiotepa Injection The metabolism of Phenytoin can be increased when combined with Thiotepa.
Vincristine Injection Vincristine Injection The serum concentration of Vincristine can be decreased when it is combined with Phenytoin.
Captopril Captopril The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Captopril.
Vinblastine Vinblastine The metabolism of Phenytoin can be increased when combined with Vinblastine.
Metoprolol Metoprolol The metabolism of Metoprolol can be increased when combined with Phenytoin.
Hydroxyzine Hydroxyzine Hydroxyzine may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.
Thiothixene Thiothixene The risk or severity of adverse effects can be increased when Phenytoin is combined with Thiothixene.
Aspirin Aspirin The serum concentration of Phenytoin can be increased when it is combined with Acetylsalicylic acid.
Salsalate Salsalate The serum concentration of Phenytoin can be increased when it is combined with Salsalate.
Chlorambucil Chlorambucil The therapeutic efficacy of Phenytoin can be decreased when used in combination with Chlorambucil.
Alprazolam Alprazolam The serum concentration of Phenytoin can be increased when it is combined with Alprazolam.
Temazepam Temazepam The risk or severity of adverse effects can be increased when Temazepam is combined with Phenytoin.
Triazolam Triazolam The risk or severity of adverse effects can be increased when Phenytoin is combined with Triazolam.
Dicyclomine Dicyclomine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Dicyclomine.
Hyoscyamine Hyoscyamine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Hyoscyamine.
Propantheline Propantheline Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Propantheline.
Trimethoprim Trimethoprim The serum concentration of Trimethoprim can be decreased when it is combined with Phenytoin.
Diltiazem Diltiazem The metabolism of Phenytoin can be decreased when combined with Diltiazem.
Nifedipine Nifedipine The serum concentration of Phenytoin can be increased when it is combined with Nifedipine.
Timolol Timolol The metabolism of Timolol can be increased when combined with Phenytoin.
Verapamil Verapamil The serum concentration of Verapamil can be decreased when it is combined with Phenytoin.
Atenolol Atenolol The metabolism of Atenolol can be decreased when combined with Phenytoin.
Pindolol Pindolol The risk or severity of adverse effects can be increased when Phenytoin is combined with Pindolol.
Cisplatin Injection Cisplatin Injection Cisplatin can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Diflunisal Diflunisal The serum concentration of Phenytoin can be increased when it is combined with Diflunisal.
Piroxicam Piroxicam The serum concentration of Phenytoin can be increased when it is combined with Piroxicam.
Bumetanide Bumetanide The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Bumetanide.
Streptozocin Streptozocin The metabolism of Phenytoin can be increased when combined with Streptozocin.
Etoposide Etoposide The metabolism of Etoposide can be increased when combined with Phenytoin.
Glyburide Glyburide The therapeutic efficacy of Glyburide can be decreased when used in combination with Phenytoin.
Glipizide Glipizide The therapeutic efficacy of Glipizide can be decreased when used in combination with Phenytoin.
Pentoxifylline Pentoxifylline The serum concentration of Pentoxifylline can be decreased when it is combined with Phenytoin.
Pentamidine Injection Pentamidine Injection The metabolism of Pentamidine can be increased when combined with Phenytoin.
Labetalol Labetalol The metabolism of Labetalol can be increased when combined with Phenytoin.
Leuprolide Injection Leuprolide Injection The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Leuprolide is combined with Phenytoin.
Gemfibrozil Gemfibrozil The metabolism of Phenytoin can be decreased when combined with Gemfibrozil.
Ketoprofen Ketoprofen The serum concentration of Phenytoin can be increased when it is combined with Ketoprofen.
Pimozide Pimozide The metabolism of Pimozide can be increased when combined with Phenytoin.
Enalapril Enalapril The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Enalapril.
Flurbiprofen Flurbiprofen The serum concentration of Phenytoin can be increased when it is combined with Flurbiprofen.
Amiodarone Amiodarone The serum concentration of Amiodarone can be decreased when it is combined with Phenytoin.
Buspirone Buspirone The metabolism of Buspirone can be increased when combined with Phenytoin.
Lovastatin Lovastatin The metabolism of Phenytoin can be decreased when combined with Lovastatin.
Ciprofloxacin Ciprofloxacin The therapeutic efficacy of Phenytoin can be decreased when used in combination with Ciprofloxacin.
Mesalamine Mesalamine The serum concentration of Phenytoin can be increased when it is combined with Mesalazine.
Diclofenac Diclofenac The serum concentration of Diclofenac can be increased when it is combined with Phenytoin.
Fluoxetine Fluoxetine The risk or severity of Anticonvulsant Toxicity can be increased when Fluoxetine is combined with Phenytoin.
Nimodipine Nimodipine The serum concentration of Phenytoin can be decreased when it is combined with Nimodipine.
Clozapine Clozapine The serum concentration of Phenytoin can be decreased when it is combined with Clozapine.
Estazolam Estazolam The risk or severity of adverse effects can be increased when Phenytoin is combined with Estazolam.
Idarubicin Idarubicin The metabolism of Phenytoin can be decreased when combined with Idarubicin.
Ofloxacin Ofloxacin The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Ofloxacin.
Clarithromycin Clarithromycin The metabolism of Phenytoin can be decreased when combined with Clarithromycin.
Etodolac Etodolac The serum concentration of Phenytoin can be increased when it is combined with Etodolac.
Felodipine Felodipine The metabolism of Phenytoin can be decreased when combined with Felodipine.
Nabumetone Nabumetone The serum concentration of Phenytoin can be increased when it is combined with Nabumetone.
Pravastatin Pravastatin The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Pravastatin is combined with Phenytoin.
Simvastatin Simvastatin The serum concentration of Simvastatin can be decreased when it is combined with Phenytoin.
Amlodipine Amlodipine The serum concentration of Phenytoin can be increased when it is combined with Amlodipine.
Teniposide Injection Teniposide Injection The serum concentration of Teniposide can be decreased when it is combined with Phenytoin.
Itraconazole Itraconazole The serum concentration of Phenytoin can be decreased when it is combined with Itraconazole.
Oxaprozin Oxaprozin The serum concentration of Phenytoin can be increased when it is combined with Oxaprozin.
Atovaquone Atovaquone The metabolism of Phenytoin can be decreased when combined with Atovaquone.
Rifabutin Rifabutin The metabolism of Phenytoin can be increased when combined with Rifabutin.
Sotalol Sotalol The metabolism of Sotalol can be decreased when combined with Phenytoin.
Zolpidem Zolpidem Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Zolpidem.
Doxazosin Doxazosin The metabolism of Doxazosin can be increased when combined with Phenytoin.
Isradipine Isradipine The serum concentration of Phenytoin can be increased when it is combined with Isradipine.
Omeprazole Omeprazole The serum concentration of Phenytoin can be increased when it is combined with Omeprazole.
Cisapride Cisapride The metabolism of Cisapride can be increased when combined with Phenytoin.
Gabapentin Gabapentin The risk or severity of adverse effects can be increased when Phenytoin is combined with Gabapentin.
Fluvastatin Fluvastatin The serum concentration of Phenytoin can be increased when it is combined with Fluvastatin.
Venlafaxine Venlafaxine The metabolism of Phenytoin can be decreased when combined with Venlafaxine.
Nizatidine Nizatidine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Nizatidine.
Stavudine Stavudine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Stavudine.
Famciclovir Famciclovir The metabolism of Famciclovir can be increased when combined with Phenytoin.
Fluvoxamine Fluvoxamine The serum concentration of Fluvoxamine can be increased when it is combined with Phenytoin.
Nefazodone Nefazodone The risk or severity of adverse effects can be increased when Phenytoin is combined with Nefazodone.
Lamotrigine Lamotrigine The serum concentration of Lamotrigine can be decreased when it is combined with Phenytoin.
Losartan Losartan The metabolism of Phenytoin can be decreased when combined with Losartan.
Tramadol Tramadol The metabolism of Phenytoin can be increased when combined with Tramadol.
Vinorelbine Injection Vinorelbine Injection The metabolism of Phenytoin can be increased when combined with Vinorelbine.
Carboplatin Injection Carboplatin Injection Carboplatin can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Lansoprazole Lansoprazole The metabolism of Phenytoin can be decreased when combined with Lansoprazole.
Ifosfamide Injection Ifosfamide Injection The metabolism of Ifosfamide can be increased when combined with Phenytoin.
Pegaspargase Injection Pegaspargase Injection The therapeutic efficacy of Phenytoin can be increased when used in combination with Pegaspargase.
Nicardipine Nicardipine The metabolism of Phenytoin can be decreased when combined with Nicardipine.
Bupropion Bupropion The metabolism of Bupropion can be decreased when combined with Phenytoin.
Ticlopidine Ticlopidine The serum concentration of Ticlopidine can be decreased when it is combined with Phenytoin.
Saquinavir Saquinavir The serum concentration of Phenytoin can be decreased when it is combined with Saquinavir.
Nisoldipine Nisoldipine The serum concentration of Phenytoin can be decreased when it is combined with Nisoldipine.
Lamivudine Lamivudine The risk or severity of myopathy, rhabdomyolysis, and myoglobinuria can be increased when Phenytoin is combined with Lamivudine.
Riluzole Riluzole The risk or severity of adverse effects can be increased when Phenytoin is combined with Riluzole.
Glimepiride Glimepiride The therapeutic efficacy of Phenytoin can be decreased when used in combination with Glimepiride.
Anastrozole Anastrozole The metabolism of Phenytoin can be decreased when combined with Anastrozole.
Indinavir Indinavir The serum concentration of Phenytoin can be decreased when it is combined with Indinavir.
Ritonavir Ritonavir The serum concentration of Ritonavir can be decreased when it is combined with Phenytoin.
Docetaxel Injection Docetaxel Injection The metabolism of Docetaxel can be increased when combined with Phenytoin.
Clomipramine Clomipramine The metabolism of Clomipramine can be increased when combined with Phenytoin.
Zafirlukast Zafirlukast The metabolism of Phenytoin can be increased when combined with Zafirlukast.
Mirtazapine Mirtazapine Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Mirtazapine.
Topiramate Topiramate The serum concentration of the active metabolites of Phenytoin can be increased when Phenytoin is used in combination with Topiramate.
Zileuton Zileuton The metabolism of Zileuton can be decreased when combined with Phenytoin.
Valsartan Valsartan The metabolism of Phenytoin can be decreased when combined with Valsartan.
Pramipexole Pramipexole Phenytoin may increase the sedative activities of Pramipexole.
Donepezil Donepezil The metabolism of Donepezil can be decreased when combined with Phenytoin.
Nelfinavir Nelfinavir The serum concentration of Nelfinavir can be decreased when it is combined with Phenytoin.
Azithromycin Azithromycin The metabolism of Azithromycin can be increased when combined with Phenytoin.
Loratadine Loratadine The metabolism of Phenytoin can be decreased when combined with Loratadine.
Carvedilol Carvedilol The metabolism of Phenytoin can be decreased when combined with Carvedilol.
Nilutamide Nilutamide The metabolism of Phenytoin can be decreased when combined with Nilutamide.
Flutamide Flutamide The risk or severity of methemoglobinemia can be increased when Phenytoin is combined with Flutamide.
Selegiline Selegiline The metabolism of Selegiline can be decreased when combined with Phenytoin.
Bicalutamide Bicalutamide The metabolism of Phenytoin can be decreased when combined with Bicalutamide.
Sertraline Sertraline The serum concentration of Phenytoin can be increased when it is combined with Sertraline.
Propafenone Propafenone The metabolism of Phenytoin can be decreased when combined with Propafenone.
Letrozole Letrozole The metabolism of Letrozole can be decreased when combined with Phenytoin.
Raloxifene Raloxifene The metabolism of Phenytoin can be decreased when combined with Raloxifene.
Irbesartan Irbesartan The metabolism of Phenytoin can be decreased when combined with Irbesartan.
Tamsulosin Tamsulosin The metabolism of Tamsulosin can be decreased when combined with Phenytoin.
Ropinirole Ropinirole The metabolism of Ropinirole can be increased when combined with Phenytoin.
Finasteride Finasteride The metabolism of Finasteride can be increased when combined with Phenytoin.
Quetiapine Quetiapine The metabolism of Quetiapine can be increased when combined with Phenytoin.
Cetirizine Cetirizine The risk or severity of adverse effects can be increased when Phenytoin is combined with Cetirizine.
Paroxetine Paroxetine The serum concentration of Phenytoin can be decreased when it is combined with Paroxetine.
Tolcapone Tolcapone The metabolism of Phenytoin can be decreased when combined with Tolcapone.
Citalopram Citalopram The metabolism of Citalopram can be decreased when combined with Phenytoin.
Capecitabine Capecitabine The serum concentration of Phenytoin can be increased when it is combined with Capecitabine.
Efavirenz Efavirenz The serum concentration of Efavirenz can be decreased when it is combined with Phenytoin.
Abacavir Abacavir The metabolism of Abacavir can be increased when combined with Phenytoin.
Sildenafil Sildenafil The metabolism of Phenytoin can be decreased when combined with Sildenafil.
Pioglitazone Pioglitazone The metabolism of Pioglitazone can be increased when combined with Phenytoin.
Celecoxib Celecoxib The serum concentration of Celecoxib can be increased when it is combined with Phenytoin.
Rosiglitazone Rosiglitazone The metabolism of Rosiglitazone can be decreased when combined with Phenytoin.
Tolterodine Tolterodine The metabolism of Tolterodine can be decreased when combined with Phenytoin.
Thalidomide Thalidomide Phenytoin may increase the central nervous system depressant (CNS depressant) activities of Thalidomide.
Aluminum Hydroxide Aluminum Hydroxide Aluminum hydroxide can cause a decrease in the absorption of Phenytoin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Colesevelam Colesevelam The serum concentration of Phenytoin can be decreased when it is combined with Colesevelam.
Balsalazide Balsalazide The serum concentration of Phenytoin can be increased when it is combined with Balsalazide.
Nateglinide Nateglinide The metabolism of Nateglinide can be decreased when combined with Phenytoin.
Galantamine Galantamine The metabolism of Galantamine can be decreased when combined with Phenytoin.
Levetiracetam Levetiracetam The risk or severity of adverse effects can be increased when Phenytoin is combined with Levetiracetam.
Rabeprazole Rabeprazole The metabolism of Phenytoin can be decreased when combined with Rabeprazole.
Terbinafine Terbinafine The metabolism of Terbinafine can be decreased when combined with Phenytoin.

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