One hundred and sixty patients undergoing laparoscopic surgery were randomly assigned to one of four groups : ( 1 ) group P ( placebo-control ) : intravenous normal saline + bilateral non-acupuncture point injection of vitamin B1 ( n = 40 ) ; ( 2 ) group O ( ondansetron ) : intravenous ondansetron + bilateral ST36 sham injection ( n = 40 ) ; ( 3 ) group A ( acupuncture point injection ) : intravenous normal saline + bilateral acupuncture point injection at ST36 of vitamin B1 ( n = 40 ) ; ( 4 ) group C ( combination ) : intravenous ondansetron + bilateral acupuncture point injection at ST36 of vitamin B1 ( n = 40 ) .