ANTICONVULSANTS, HYDANTOIN

Brand & Generic Names

Dilantin	Diphenylhydantoin
Dilantin-30	ETHOTOIN
Dilantin-125	MEPHENYTOIN
Dilantin Infatabs	Mesantoin
Dilantin Kapseals	Peganone
Dilantin-30-Pediatric	Phenytex
Diphenylan	PHENYTOIN

Basic Information

• Habit forming? No
• Prescription needed? Yes
• Available as generic? Yes
• Drug class: Anticonvulsant (hydantoin)

Uses

• Prevents some forms of epileptic seizures.
• Stabilizes irregular heartbeat.

Dosage & Usage Information

How to take:
Tablet--Swallow with liquid.
Chewable tablets--Chew well before swallowing.
Suspension--Shake well before taking with liquid.

When to take:
At the same time each day.

If you forget a dose:
If drug taken 1 time per day--Take as soon as you remember up to 12 hours late. If more than 12 hours, wait for next scheduled dose (don't double this dose).
If taken several times per day--Take as soon as possible, then return to regular schedule.

What drug does:
Promotes sodium loss from nerve fibers. This lessens excitability and inhibits spread of nerve impulses.

Time lapse before drug works:
7 to 10 days continual use.

Don't take with:
Any other medicine without consulting your doctor or pharmacist.

Overdose

SYMPTOMS:
Jerky eye movements; stagger; slurred speech; imbalance; drowsiness; blood pressure drop; slow, shallow breathing; coma.

WHAT TO DO:

• Dial 911 (emergency) or 0 (operator) for an ambulance or medical help. Then give first aid immediately.
• See EMERGENCY information.

Possible Adverse Reactions or Side Effects

Life-threatening:

Severe allergic Seek emergency help. reaction (rash, fever, swollen glands, kidney failure).

Common:

Mild dizziness, drowsi- ness; nausea; vomiting; constipation; bleeding, swollen or tender gums.

Infrequent:

• Hallucinations, confusion, slurred speech, stagger, rash, change in vision, agitation.
• Headache, diarrhea, muscle twitching.
• Increased body and facial hair, breast swelling, insomnia.

Rare:

Sore throat, fever, unusual bleeding or bruising, abdominal pain, jaundice.

Warnings & Precautions

Don't take if:
You are allergic to any hydantoin anticonvulsant.

Before you start, consult your doctor:

• If you have impaired liver function or disease.
• If you will have surgery within 2 months, including dental surgery, requiring dental or spinal anesthesia.
• If you have diabetes.
• If you have a blood disorder.

Over age 60:
Adverse reactions and side effects may be more frequent and severe than in younger persons.

Pregnancy:
Studies inconclusive about harm to unborn child. Decide with your doctor if drug benefits justify risk to unborn child.

Breast-feeding:
Drug passes into milk. Avoid drug or discontinue nursing until you finish medicine. Consult doctor for advice on maintaining milk supply.

Infants & children:
Use only under medical supervision.

Prolonged use:

• Weakened bones.
• Lymph gland enlargement.
• Possible liver damage.
• Numbness and tingling of hands and feet.
• Continual back-and-forth eye movements.
• Talk to your doctor about the need for follow-up medical examinations or laboratory studies to check complete blood counts (white blood cell count, platelet count, red blood cell count, hemoglobin, hematocrit), liver function, EEG*.

Skin & sunlight:
May cause rash or intensify sunburn in areas exposed to sun or sunlamp.

Driving, piloting or hazardous work:
Don't drive or pilot aircraft until you learn how medicine affects you. Don't work around dangerous machinery. Don't climb ladders or work in high places. Danger increases if you drink alcohol or take medicine affecting alertness and reflexes.

Discontinuing:
Don't discontinue without consulting doctor. Dose may require gradual reduction if you have taken drug for a long time. Doses of other drugs may also require adjustment.

Others:
May cause learning disability.

Possible Interaction with Other Drugs

GENERIC NAME	COMBINED EFFECT
-------------------------	-----------------------
Amiodarone	Increased anticonvulsant effect.
Antacids*	Decreased anticonvulsant effect.
Anticoagulants*	Increased effect of both drugs.
Antidepressants,	May need to adjust anticonvulsant dose.
Barbiturates*	Changed seizure pattern.
Calcium	Decreased effects of both drugs.
Carbamazepine	Possible increased anticonvulsant
	metabolism.
Carbonic anhydrase	Increased chance of bone disease.
Central nervous	Oversedation.
Chloramphenicol	Increased anticonvulsant effect.
Cimetidine	Increased anticonvulsant toxicity.
Contraceptives, oral*	Increased seizures.
Cortisone drugs*	Decreased cortisone effect.
Cyclosporine	May decrease cyclosporine effect.
Digitalis	Decreased digitalis effect.
Disopyramide	Decreased disopyramide effect.
Disulfiram	Increased anticonvulsant effect.
Estrogens*	Increased estrogen effect.
Felbamate	Increased side effects and adverse
	reactions.
Fluconazole	Increased anticonvulsant effect.
Furosemide	Decreased furosemide effect.
Gold compounds*	Increased anticonvulsant blood levels.
	Hydantoin dose may require adjustment.
Glutethimide	Decreased anticonvulsant effect.
Griseofulvin	Increased griseofulvin effect.
Hypoglycemics, oral*	Possible decreased hypoglycemic effect.
Hypoglycemics, other*	Possible decreased hypoglycemic effect.
Isoniazid	Increased anticonvulsant effect.
Itraconazole	Decreased itrconazole effect.
Leucovorin	May counteract the effect of phenytoin
	or any hydantoin anticonvulsant.
Loxapine	Decreased anticonvulsant effect of
	phenytoin or any hydantoin anti-
	convulsant.
MAO inhibitors*	Increased polythiazide effect.
Methadone	Decreased methadone effect.
Methotrexate	Increased methotrexate effect.
Methylphenidate	Increased anticonvulsant effect.
Molindone	Increased phenytoin effect.
Nicardipine	Increased anticonvulsant effect.
Nimodipine	Increased anticonvulsant effect.
Nitrates*	Excessive blood pressure drop.
Nizatidine	Increased effect and toxicity of
	phenytoin.
Omeprazole	Delayed excretion of phenytoin
	causing increased amount of phenytoin
	in blood.
Oxyphenbutazone	Increased anticonvulsant effect.
Para-aminosalycylic	Increased anticonvulsant effect.
Paroxetine	Decreased anticonvulsant effect.
Phenacemide	Increased risk of paranoid symptoms.
Phenothiazines*	Increased anticonvulsant effect.
Phenylbutazone	Increased anticonvulsant effect.
Potassium supplements*	Decreased potassium effect.
Probenecid	Decreased probenecid effect.
Propafenone	Increased effect of both drugs and
	increased risk of toxicity.
Propranolol	Increased propranolol effect.
Quinidine	Increased quinidine effect.
Rifampin	Decreased anticonvulsant effect.
Sedatives*	Increased sedative effect.
Sotalol	Decreased sotalol effect.
Sucralfate	Decreased anticonvulsant effect.
Sulfa drugs*	Increased anticonvulsant effect.
Theophylline	Reduced anticonvulsant effect.
Trimethoprim	Increased phenytoin effect.
Valproic acid	Breakthrough seizures.
Xanthines*	Decreased effects of both drugs.

Possible Interaction with Other Substances

INTERACTS WITH	COMBINED EFFECT
---------------	---------------
Alcohol:	Possible decreased anticonvulsant
	effect. Use with caution.
Beverages:	None expected.
Cocaine:	Possible seizures.
Foods:	None expected.
Marijuana:	Drowsiness, unsteadiness, decreased
	anticonvulsant effect.
Tobacco:	None expected.