Abstract
Promazine hydrochloride (Sparine) and chlorpromazine hydrochloride (Thorazine) were incorporated in 20% egg yolk extenders of the CU-16 type at levels as high as 2,000 [mu]g/ml extender. None of the levels of promazine tested improved sperm survival, and the highest levels of both drugs were spermicidal (P 0.05). While all 3 extenders gave highly acceptable fertility, there appears to be no advantage in replacing sulfanilamide with chlorpromazine in the extenders used in these experiments.