“In mice, 200 mg per kilogram of nicotinamide increased the half-life of primidone by 47.6%, and the conversion to phenobarbital and phenylethylmalonamide was decreased by 32.4% and 14.5%, respectively.”
“ Nicotinamide also decreased the conversion of primidone to phenobarbital in patients.”
“The data demonstrate that nicotinamide inhibits metabolism of primidone in mice and metabolism of primidone and carbamazepine in humans.”