Interaction of mescaline with phenothiazines: effect on behavior, body temperature, and tissue levels of hallucinogen in mice.

Mescaline (25 mg/kg; 66 muc/kg) was injected (ip) in mice 45 min before chlorpromazine (CPZ, 2.5, 5, 15 mg/kg), thioridazine (10, 30, 45 mg/kg), or chlorpromazine-sulfoxide (CPZ-SO, 15 mg/kg). Excitement, agitation, slight increase in ventilation and occasional head-shaking were seen 30 min after mescaline and continued for 30-45 min thereafter; locomotor activity and the number of scratching events were significantly increased during this period. CPZ (2.5, 5, 15 mg/kg) and thioridazine (10, 30, 45 mg/kg) partially or completely blocked mescaline-induced gross behavior; CPZ-SO (15 mg/kg) was not effective. Increased scratching responses and locomotor activity induced by mescaline were antagonized by all doses of CPZ and thioridazine; at higher doses, both CPZ (7.5, 15 mg/kg) and thioridazine (45 mg/kg) induced cataleptic-like condition and marked hypothermia. Tissue levels of mescaline, examined 3 hr after its administration, were increased by all doses of CPZ and a higher dose of thioridazine (45 mg/kg); CPZ-SO and lower doses of thioridazine had no effect.