Question

Drug card for

Hydantoins

phenytoin (Dilantin)

Answer 1

ANTIEPILEPTIC

CHEMICAL NAME =PHENYTOIN (CLASSIFICATION -HYDANTOIN)

BRAND NAME= DILANTIN

FORMS= capsule,tablet, suspension, injection

USES

Generalised tonic-clonic seizures, partial seizures

MECHANISM OF ACTION

• blocks sodium channel and prevents post-tetanic potentiation limits the development of seizure activity and reduces the spread of the seizure.
• inhibits calcium influx ,result in preventing neurotransmission at the level of synapse

HALF LIFE-

12-24 hours and progressively increases when plasma concentration rises.

ADVERSE EFFECTS

CNS effects, skin rash, teratogenic, Gingival hyperplasia, cardiovascular, endocrine effects, Vitamin D metabolism

CONTRAINDICATION

Sinus bradycardia, SA blocks,2 nd and 3 rd degree AV blocks

INTERACTIONS

• oral contraceptives, warfarin,glucocoticoids inhibits metabolism with phenytoin
• carbamazepine, phenobarbital, decrease phenytoin level
• diazepam, cimetidine, valproic acid increase phenytoin levels

EDUCATION

• use slow IV route for status epilepticus
• antidysrhythmics