Interaksi Fosfenitoin dan Tiagabin

Use of tiagabine HCl without enzyme-inducing antiepileptic drugs results in blood levels about twice those attained in the studies on which current dosing recommendations are based (see DOSAGE AND ADMINISTRATION ).

Tiagabine HCl is considered to be a non-enzyme inducing AED (see PRECAUTIONS, General, Use in Non-Induced Patients ).

…tiagabine HCl dosing recommendations in current labeling for treatment of epilepsy were based on use in patients with partial seizures 12 years of age and older, most of whom were taking enzyme-inducing antiepileptic drugs (AEDs; e.g., carbamazepine, phenytoin, primidone and phenobarbital) which lower plasma levels of tiagabine HCl by inducing its metabolism.

Carbamazepine, phenytoin, primidone, and phenobarbital are generally classified as enzyme inducers; valproate and gabapentin are not.

Effects of other Antiepilepsy Drugs (AEDs) on Tiagabine HCl: Carbamazepine : Population pharmacokinetic analyses indicate that tiagabine clearance is 60% greater in patients taking carbamazepine with or without other enzyme-inducing AEDs.

Limited evidence suggests that HLA-B*1502 may be a risk factor for the development of SJS/TEN in patients of Asian ancestry taking other antiepileptic drugs associated with SJS/TEN, including phenytoin.

…defects), and abnormalities characteristic of fetal hydantoin syndrome, including dysmorphic skull and facial features, nail and digit hypoplasia, growth abnormalities (including microcephaly), and cognitive deficits, have been reported among children born to epileptic women who took phenytoin alone or in combination with other antiepileptic drugs during pregnancy.