Indication:
Phenytoin is used to control generalized tonic clonic (grand mal) and complex
partial (temporal lobe) seizures and for the prevention and treatment of seizures
occurring during or following neurosurgery.
Possible side effects: Imbalance, slurred speech, decreased
coordination, mental confusion, dizziness, and nervousness can occur and are
usually dose related. Other problems reported include skin rash, gum problems,
and excessive hair growth.
You need to be aware that with any changes in your anticonvulsant therapy, there
may be an increase in seizure frequency. Keep in mind that side effects vary
among individuals. If you have any problem with medication, you should let your
doctor know, whether or not it is problem listed above.
Dosage: Dilantin is supplied in 100mg (orange band) and 30mg
(pink band) capsules. Phenytek is supplied as 300mg capsules. For pediatric
patients, Dilantin is also available in 50mg infatabs and oral suspension. The
usual adult dosage is 100mg three or four times daily. However, a higher dose
may be given if necessary. If seizure control is well established, phenytoin
may be taken once a day.
Drug Interactions: Phenytoin binds with plasma protein and can be displaced by other drugs that bind in the same way. This might result in the elevation of the unbound phenytoin level. The following are highly bound drugs: thyroid hormones, tricyclic antidepressants, oral hypoglycemic agents, sulfonamides, salicylates, diazoxide, clofibrate, phenylbutazone, bishydroxycoumarin, and valproic acid.
Also, at high doses, antacids containing calcium, magnesium or aluminum may
reduce the absorption of phenytoin.
Oral contraception: The efficacy of some birth control pills
can be affected by phenytoin. In these cases, phenytoin can lower the estrogen
levels of the birth control pills. This can be remedied by taking a birth control
pill with a higher level of estrogen. Check with your doctor.
Blood levels: The usual blood levels for phenytoin range between 10 and 25 ug/ml. However, some people do well with lower levels. In others good seizure control without side effects is achieved with levels of 30ug/ml or more. If you are not having side effects and are still having seizures your doctor may consider doses which result in higher blood levels.