Vigabatrin Primidone

Anticonvulsants (barbiturates, including phenobar-bital and primidone carbamazepine felbamate phenytoin topiramate vigabatrin)... 

VIGABATRIN 1. BARBITURATES-phenobarbital, primidone 2. PHENYTOIN i levels of these antiepileptics Possibly induction of metabolism Watch for poor response to these antiepileptics... 

Clinically important, potentially hazardous interactions with carbamazepine, lamotrigine, phenobarbital, primidone, topiramate, valproic acid, vigabatrin... 

Vigabatrin causes a trivial decrease in phenobarbital and primidone levels. There is some evidence that phenobarbital may reduce the efficacy of vigabatrin in infantile spasms. 

In an early clinical study, vigabatrin 2 to 3 g daily did not change the serum levels of phenobarbital in 26 patients. Similarly, another study found that phenobarbital levels were not significantly altered by vigabatrin. Another study found that vigabatrin caused serum level reductions of 7% with phenobarbital and 11% with primidone. Alterations of this size would not be expected to be clinically significant. 

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