Carbamazepine attenuates cocaine-induced increases in dopamine in the nucleus accumbens: an in vivo dialysis study.

Carbamazepine's effects on cocaine-induced increases in dopamine overflow in the nucleus accumbens were studied using in vivo microdialysis in anesthetized rats. Rats were chronically treated with a diet containing carbamazepine or no drug for one week prior to microdialysis procedures. The basal levels of dopamine in the nucleus accumbens did not differ between groups; however, the increases in dopamine following cocaine administration (4 mg/kg i.v.) were significantly reduced by carbamazepine. In addition, basal levels of dihydroxyphenyl acetic acid (DOPAC) were significantly diminished in the carbamazepine group and a trend in the same direction was observed for homovanilic acid (HVA). These results are consistent with reports that carbamazepine might decrease dopamine synthesis. Further studies are required to determine the mechanism of carbamazepine's inhibition of cocaine-induced dopamine overflow and its potential clinical implications.