Long term effect of teflutixol on apomorphine-induced stereotypy and vomiting in dogs.

Dose--response relationships to apomorphine-induced vomiting and stereotyped running behaviour have been determined in dogs before, and up to 24 and 28 days respectively, after daily oral treatment with 2.5 mg/kg of teflutixol or 12 days. The ED50 values for apomorphine-induced vomiting after teflutixol were not different from those obtained before treatment. Stereotyped running behaviour of increasing intensity was seen 4--12 days after teflutixol treatment. The intensity then declined and returned to normal. The results suggest that the nigro-neostriatal dopamine system in dogs became hypersensitive after prolonged teflutixol treatment, while the dopamine receptors of the emetic chemotrigger zone did not.