Abstract
The relative potencies of phenothiazine derivatives to suppress the avoidance responses in the rats which were conditioned in a high degree were determined as follows: promazine 1, chlorpoomazine 0.8, acetylpromazine 1.3, trimeprazine 0.7, levomepromazine 2.9, triflupromazine 3.2, prochlorperazine 3.7, perphenazine 21.4, thioproperazine 35.4, trifluoherazine 39.7 and trifluphenazine 43.8. The dimethylamino derivatives induced the rapid action and its duration was shorter except chlorpromazine and triflupromazine which had a longer lasting effect even with a rapid induction while the piperazine derivatives showed the slow induction and the effect lasted longer as a rule.
