Abstract
Abstract Administration of chlorpromazine at ( 50 mg / kg / day ) orally for a period of 21 days resulted in a significant increase in chick blood plasma and RBC acetyl cholinesterase activity by 48 % and 62% respectively , where as only a slight and non significant increase by 9% and 13% respectively was observed when diazepam was given at ( 30 mg / kg / day ) orally in comparison with control group .The result suggest that chronic treatment with chlorpromazine may stimulate blood acetyl cholinesterase activity in chicks .