DILANTIN (Phenytoin)

What is this medication?

DILANTIN (Phenytoin)
Anticonvulsive Agent, Hydantoin

DILANTIN (Phenytoin) is officially indicated for focal seizures and status epilepticus.  It is also prescribed off label for prevention of other seizure types.

ALERT: WARNING
The rate of intravenous phenytoin administration should not exceed 50 mg/minute in adults and 1 to 3 mg/kg/minute (or 50 mg/minute, whichever is slower) in pediatric patients because of the risk of severe hypotension and cardiac arrhythmias. Careful cardiac monitoring is needed during and after administering intravenous phenytoin. Although the risk of cardiovascular toxicity increases with infusion rates above the recommended infusion rate, these events have also been reported at or below the recommended infusion rate. Reduction in rate of administration or discontinuation of dosing may be needed.

How does this medication work? 

DILANTIN (Phenytoin) stabilizes the neuronal cell membrane and decreases intracellular sodium ions in neurons in motor cortex during generation of nerve impulses.  It also prolongs the refractory period and suppresses ventricular pacemaker automaticity and shortens the cardiac action potential.

How should I take this medication? 

Oral: Take 100mg two to four times per day and adjust based on patient response and serum concentrations.  Sometimes larger loading dosages are used for faster effect.

How to Take: Follow instructions provided by physician/pharmacy label, swallow whole, take consistently at same times each day unless otherwise directed.

What should I watch for while using this medication? 

Before starting DILANTIN (Phenytoin), make sure your physician is aware of any allergies or medications you currently take, if you have any heart rhythm disorders, other cardiovascular disease, liver disease,  kidney disease, diabetes, hypoalbuminemia, hypothyroidism, porphyria, or are pregnant or breastfeeding.

Do not stop this medication quickly.  It should be withdrawn over 2-6 months or gradually transitioned to another antiepileptic agent to minimize potential of increased seizure frequency unless it must be withdrawn quickly due to safety reasons.  This medication has a narrow therapeutic index and many drug interactions so make sure to ask your physician or pharmacist before starting any natural supplements or new medications.  May cause sedation; be careful mixing with alcohol due to enhanced impairment.  Alcohol may also affect blood levels of phenytoin so it should be consumed minimally and carefully.  

What if I miss a dose?

If you miss a dose of medication, try to take it as soon as possible. However, if it is almost time for your next dose, take only that scheduled dose. Do not take double or extra doses.

How should I store this medication?

Keep out of the reach of children at all times. Store at room temperature, 59 to 86° F (15 to 30° C). Protect from light. Keep the container tightly closed. Properly dispose of any unused medication after the expiration date.

What are the possible side effects of using this medication?

Nausea, vomiting, rash, nystagmus, ataxia, slurred speech, dizziness, confusion, paresthesia, blurred vision, somnolence, constipation, headache, insomnia, altered taste, tremor, hyperglycemia.

Note this is not a complete list of side effects for DILANTIN (Phenytoin), only common ones.