GENERIC NAME: PHENYTOIN SODIUM CAPSULES - ORAL (fen-eh-TOE-in, FEN-eh-toyn)
BRAND NAME(S): Dilantin
Medication Uses | Other Uses | How To Use | Side Effects | Precautions | Drug Interactions | Overdose | Notes | Missed Dose | Storage | Medical Alert
USES: Phenytoin is used to prevent and control seizures (also called an anticonvulsant or antiepileptic drug). It works by reducing the spread of seizure activity in the brain.
OTHER USES: This drug may also be used to treat certain types of irregular heartbeats and painful nerve conditions (e.g., trigeminal neuralgia).
HOW TO USE: Take this medication by mouth usually 2 or 3 times a day, or as directed by your doctor. This product is not recommended for use once a day. You may take it with food if stomach upset occurs. Take this medication with a full glass (8 oz or 240 ml) of water unless your doctor directs you otherwise. Do not lie down for at least 30 minutes after taking this drug. Swallow the capsules whole. Do not use the capsules if discolored. Use this medication regularly in order to get the most benefit from it. It is important to take all doses on time to keep the amount of medicine in your body at a constant level. Remember to use it at the same times each day. Dosage is based on your medical condition and response to therapy. Antacids or nutritional tube-feeding (enteral) products which contain calcium may decrease the absorption of phenytoin. If you are using any such products, separate taking them from phenytoin by at least 2 hours. Do not stop taking this medication without consulting your doctor. Seizures may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased.
SIDE EFFECTS: Headache, nausea, vomiting, constipation, dizziness, drowsiness, trouble sleeping, or nervousness may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly. Phenytoin may cause swelling and bleeding of the gums. Massage your gums and brush and floss your teeth regularly to minimize this problem. See your dentist regularly. Tell your doctor immediately if any of these unlikely but serious side effects occur: unusual eye movements, loss of coordination, slurred speech, confusion, muscle twitching, double or blurred vision, tingling of the hands/feet, facial changes (e.g., swollen lips, butterfly-shaped rash around the nose/cheeks), excessive hair growth, increased thirst or urination, unusual tiredness, bone or joint pain, easily broken bones, painful erections. Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: uncontrolled muscle movements, swollen glands (lymph nodes), stomach/abdominal pain, persistent nausea/vomiting, yellowing eyes or skin, dark urine, easy bruising/bleeding, signs of infection (e.g., persistent sore throat or fever). A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, high fever, itching, swelling, severe dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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