Drug Interaction Report

MONITOR: Large doses of pyridoxine (greater than 200 mg/day) may decrease the concentration of certain antiepileptic medications, including phenytoin and phenobarbital. The mechanism of this interaction is not known.

MANAGEMENT: If large doses of pyridoxine must be used concomitantly with these medications, close observation for evidence of altered anticonvulsant effect is recommended. Patients should be advised to notify their caregiver if they experience loss of seizure control.

GENERALLY AVOID: Concurrent acute use of barbiturates and ethanol may result in additive CNS effects, including impaired coordination, sedation, and death. Tolerance of these agents may occur with chronic use. The mechanism is related to inhibition of microsomal enzymes acutely and induction of hepatic microsomal enzymes chronically.

MANAGEMENT: The combination of ethanol and barbiturates should be avoided.