Proper Use

Drug information provided by: Micromedex

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.

This medicine may be used with other seizure medicines. Keep using all of your seizure medicines unless your doctor tells you to stop.

Do not change brands or dosage forms of phenytoin without first checking with your doctor. Different products may not work the same way. If you refill your medicine and it looks different, check with your pharmacist.

Swallow the tablet whole or chew it thoroughly before being swallowed together with a glass of water.

Measure the oral suspension with a marked measuring spoon, oral syringe, or medicine cup. Rinse the dosing spoon or cup with water after each use.

If you are receiving tube feeding preparations, it is best to take this medicine before or after a feeding.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For seizures:
    • For oral dosage form (extended-release capsules):
      • Adults—At first, 100 milligrams (mg) three times a day or 300 mg once a day. Your doctor may increase your dose as needed. For patients in the clinic or hospital (except with a history of liver or kidney disease), a loading dose of 1000 mg is divided into three doses (400 mg, 300 mg, 300 mg) and given every 2 hours. Then, normal maintenance dose may be started 24 hours after the loading dose.
      • Teenagers and children older than 6 years of age—300 mg per day. Your doctor may adjust your dose as needed.
      • Children 6 years of age and below—Dose is based on body weight and must be determined by your doctor. At first, 5 milligrams (mg) per kilogram (kg) of body weight given in two or three divided doses per day. The doctor may adjust the dose as needed.
    • For oral dosage form (suspension):
      • Adults—At first, 5 milliliters (mL) or one teaspoonful three times a day. Your doctor may adjust your dose as needed.
      • Teenagers and children older than 6 years of age—300 mg per day. Your doctor may adjust your dose as needed.
      • Children 6 years of age and below—Dose is based on age and body weight and must be determined by your doctor. At first, 5 milligrams (mg) per kilogram (kg) of body weight given in two or three divided doses per day. Your doctor may adjust your dose as needed.
    • For oral dosage form (tablets):
      • Adults—At first, 100 milligrams (mg) three times a day. Your doctor may adjust your dose as needed.
      • Teenagers and children older than 6 years of age—300 mg per day, given in two or three divided doses per day. Your doctor may adjust your dose as needed.
      • Children 6 years of age and below—Dose is based on age and body weight and must be determined by your doctor. At first, 5 milligrams (mg) per kilogram (kg) of body weight given in two or three divided doses per day. The doctor may adjust the dose as needed.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.