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PHENYTOIN - a patient's guide


This medication is used to control seizures in epileptics. This article discusses the use and side effects of the drug.

Brand name:



Anti-Convulsant, antiarrhythmic.

Phenytoin is commonly used in the management of disorders which involve seizures, such as epilepsy. It may also be given to preventative seizures following head injury. Phenytoin is also occasionally used to treat heart arrhythmias.


  • Liver disease or impairment
  • Pregnancy and breast feeding
  • Elderly patients

Side effects:

  • Trouble sleeping
  • Headache
  • Dizziness and hand tremors
  • Stomach upset
  • Increased thirst and increased urine frequency
  • Skin rush
  • Enlargement of gums and thickening of facial hair
  • Involuntary movement of eye and impaired movement of the body
  • Confusion, unsteady movement and slurred speech


Phenytoin interacts with many common medications such as steroids, oral contraceptives, and some antibiotics. Always speak to your doctor or pharmacist before starting any new medication while taking phenytoin.

Patient information:

  • Follow instructions carefully on the label of the medication.
  • Take at the same time each day, take with food to reduce stomach irritation.
  • Do not stop taking this medication except on doctors advice.
  • Do not take antacids or calcium rich products at the same time as Phenytoin, allow a 1 to 2 hour space between them.
  • Special care should be taken with oral hygiene to prevent gum problems.
  • Do not take any new medicines without consulting your doctor or pharmacist first.
  • See your doctor if severe side effects occur, e.g. skin rash.

See also:

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