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Phenytoin injection

What is this medicine?

PHENYTOIN (FEN i toyn) is used to control seizures in certain types of epilepsy. It is also used to prevent seizures during or after surgery.

How should I use this medicine?

This medicine is for injection into a vein. It is given by a health care professional in a hospital or clinic setting.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for selected conditions, precautions do apply.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

  • breathing problems

  • changes in vision

  • chest pain or tightness

  • confusion

  • dark yellow or brown urine

  • fast or irregular heartbeat

  • fever, sore throat

  • headache

  • loss of seizure control

  • poor control of body movements or difficulty walking

  • redness, blistering, peeling or loosening of the skin, including inside the mouth

  • unusual bleeding or bruising, pinpoint red spots on skin

  • vomiting

  • worsening of mood, thoughts or actions of suicide or dying

  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • constipation

  • difficulty sleeping

  • excessive hair growth on the face or body

  • nausea

What may interact with this medicine?

Do not take this medicine with any of the following medications:

  • certain medicines used to treat HIV infection or AIDS that are given in combination with cobicistat

  • delavirdine

  • ibrutinib

  • ranolazine

This medicine may also interact with the following medications:

  • albendazole

  • alcohol

  • - aspirin and aspirin-like medicines

  • certain medicines for blood pressure like nifedipine, nimodipine, and verapamil

  • certain medicines for cancer

  • certain medicines for cholesterol like atorvastatin, simvastatin, and fluvastatin

  • certain medicines for depression, anxiety, or psychotic disturbances

  • certain medicines for fungal infections like ketoconazole and itraconazole

  • certain medicines for irregular heart beat like amiodarone and quinidine

  • certain medicines for seizures like carbamazepine, phenobarbital, and topiramate

  • certain medicines for stomach problems like cimetidine and omeprazole

  • chloramphenicol

  • cyclosporine

  • diazoxide

  • digoxin

  • disulfiram

  • doxycycline

  • female hormones, like estrogens and birth control pills

  • furosemide

  • halothane

  • isoniazid

  • medicines that relax muscles for surgery

  • medicines used to treat HIV infection or AIDS

  • methylphenidate

  • narcotic medicines for pain

  • phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine

  • praziquantel

  • reserpine

  • rifampin

  • St. John's Wort

  • steroid medicines like prednisone or cortisone

  • sulfonamides like sulfamethoxazole or sulfasalazine

  • supplements like folic acid or vitamin D

  • theophylline

  • ticlopidine

  • tolbutamide

  • warfarin

What if I miss a dose?

This does not apply.

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • an alcohol abuse problem

  • Asian ancestry

  • diabetes

  • heart problems

  • liver disease

  • low blood pressure

  • suicidal thoughts, plans, or attempt; a previous suicide attempt by you or a family member

  • an unusual or allergic reaction to phenytoin, hydantoin or other medicines, foods, dyes, or preservatives

  • pregnant or trying to get pregnant

  • breast-feeding

What should I watch for while using this medicine?

Your condition will be monitored carefully while you are receiving this medicine.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

The use of this medicine may increase the chance of suicidal thoughts or actions. Pay special attention to how you are responding while on this medicine. Any worsening of mood, or thoughts of suicide or dying should be reported to your health care professional right away.

NOTE:This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider. Copyright© 2021 Elsevier