Prolonged treatment with carbamazepine increases the stimulatory effects of ethanol in mice.

Carbamazepine (CBZ) has been used in the treatment of alcohol withdrawal (AW). However, cases of induction of euphoric feelings when mixed with alcohol have been reported. We verified whether CBZ could potentiate ethanol stimulatory effects in animals. Two groups of mice were injected with saline (group I) or 2 g/kg ethanol (group II) IP, for 20 days. On the next day, each group was divided into two subgroups that received either a single dose of CBZ (10 mg/kg) or vehicle IP, followed, 30 min later, by saline or ethanol injection. Locomotor activity was measured. Acute CBZ did not change locomotor activity of ethanol-treated mice. Treatment with CBZ or vehicle continued for 6 days. Finally, on the 28th day, 30 min after the last CBZ or vehicle injection, an ethanol challenge was given to group II and a saline injection to group I. The results showed a significant potentiation of ethanol stimulatory effects by chronic CBZ treatment. Data indicated that CBZ should be cautiously administered to alcohol-dependent patients.