SEX-DIFFERENCES IN PHARMACOKINETICS OF ORAL PROPRANOLOL IN HEALTHY CHINESE VOLUNTEERS

AIM: To determine if the gender-based dimorphism of the distribution a nd metabolism of oral propranolol (Pro) exists in the healthy Chinese volunteers. METHODS: Twelve subjects (6 M and 6 F) were given an 80 mg single oral dose of Pro. Plasma Pro levels were determined by HPLC wi th fluorescence detector and the pharmacokinetic parameters were calcu lated by using the MCPKP program. RESULTS: AUC and C-max in females we re about 74 % and 99 % higher than those in males (P <0.05), whereas o ral clearance and apparent distribution volume were 109 % and 120 % lo wer in females than in males (P <0.05), respectively. The T 1/2 tended to be longer in females (P >0.05). No differences in any other kineti c parameters were found between the sexes. CONCLUSION: The higher oral bioavailability (AUC and C-max) of Pro in Chinese women is in part ca used by their lower oral clearance and volume of distribution.