CIMETIDINE-INDUCED RISE IN PRAZIQUANTEL LEVELS IN A PATIENT WITH NEUROCYSTICERCOSIS BEING TREATED WITH ANTICONVULSANTS

A patient had neurocysticercosis complicated by a seizure disorder req uiring anticonvulsants; previous praziquantel therapy (50 mg/kg/day) h ad failed to eradicate the disease. In an attempt to inhibit cytochrom e P-450 metabolism of praziquantel, cimetidine (1600 mg/day) was coadm inistered. Before addition of cimetidine, the maximum concentration of praziquantel was 350 ng/mL; concurrent cimetidine administration incr eased the maximum concentration to 826 ng/mL. The elimination half-lif e increased from 1.7 h without cimetidine to 3.3 h with cimetidine and the area under the curve for the 12-h sampling period rose from 754 n g.h/mL to 3050 ng.h/mL. Coadministration of cimetidine raises serum pr aziquantel levels and may be helpful in patients treated concomitantly with praziquantel and anticonvulsants.