Epilepsy Ontario :: Medications

Phenytoin Sodium

Phenytoin is available in Canada by prescription only.

Known as	Dilantin�, Dilantin� Infatabs, Dilantin�-30 Pediatric, Dilantin�-125 Diphenylhydantoin Diphenylan
Uses	Phenytoin is used to control generalized tonic-clonic seizures, simple partial, and complex partial seizures, though occasional seizure activity may still occur. It is rarely used in children.
How to Use	The actual dosage will vary until the doctor stabilizes the blood levels needed for maximum therapeutic dosage. Phenytoin is taken by mouth or administered by injection in the hospital.
Side Effects	Common side effects of phenytoin may include slurred speech, dizziness, insomnia, coordination problems, constipation, nausea and vomiting. Use over a long period may also result in some connective tissue damage. Coarsening of facial features, overgrowth of the gums, and enlargement of the lips may occur.
Precautions	Seniors and those with impaired liver function should be under close medical supervision because the liver is to susceptible to phenytoin. People with diabetes should be cautious taking phenytoin because it may inhibit the release of insulin in the body. If a skin rash results when taking phenytoin, seek an alternate drug from your doctor immediately. Do not stop taking phenytoin abruptly. This can precipitate status epilepticus.
Interactions	The following may increase the level of phenytoin in the blood: alcohol (acute intake) amiodarone amphotericin B chloramphenicol chlordiazepoxide cimetidine (Tagamet�) diazepam diltiazem dicumarol disulfiram erythromycin estrogens ethosuximide fluconazole fluoxetine halothane isoniazid itraconazole ketoconazole methylphenidate miconazole nifedipine omeprazole phenothiazines phenylbutazone salicylates (ASA) succinimides sulfonamides ticlopidine tolbutamide topiramate trazodone � The following may decrease the level of phenytoin in the blood: antacids containing calcium antibacterial agents/fluoroquinolones (ciprofloxacin, rifampin) carbamazepine alcohol (chronic abuse) diazoxide folic acid resperpine sucralfate theophylline vigabatrin � The following may either increase or decrease the level of phenytoin in the blood: carbamazepine chlordiazepoxide diazepam phenobarbital sodium valproate valproic acid � Phenytoin may decrease the effects of: acetaminophen (Tylenol�) topiramate � Phenytoin may either increase or decrease the level of: carbamazepine phenobarbital sodium valproate valproic acid � Phenytoin may effect the blood level and/or alter the effects of: chlorpropamide digitoxin doxycycline estrogens glyburide methadone nicardipine nimodipine oral contraceptives pancuronium praziquantel quinidine rifampin tetracycline tolbutamide verapamil vecuronium � If you are using any over-the-counter medication, inform doctor or pharmacist: some medications may increase the phenytoin level in the blood; others may decrease it. � Mothers considering breast feeding should consult their physician: small amounts of phenytoin may be passed in human milk. � Tip – Do not consume too much alcohol as it upsets the blood serum levels of phenytoin.
Missed Dose	Take next dose as soon as you remember, then resume medication as usual. Do not double-up dosage to catch up on therapeutic effect.
Storage	Store at room temperature, between 15�C and 30�C, away from children, heat, light and moisture.
Forms	Capsules: adults - 300 to 400 mg daily; children - 4 to 8 mg/kg daily; (infants) 30 mg Tablets (flavoured, chewable); Liquid

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Disclaimer

The material offered at this site is to provide general information about epilepsy to the public. It is not intended to be taken as medical advice. Although all material presented at this site has been thoroughly researched and is believed to be correct, Epilepsy Ontario accepts no liability. Consult your physician and/or neurologist with any questions you have. People with epilepsy should never discontinue anti-epileptic medications or make changes in activities unless specifically advised to do so by an attending physician.