The interaction effect of perioperative cotreatment with dextromethorphan and intravenous lidocaine on pain relief and recovery of bowel function after laparoscopic cholecystectomy.

Both dextromethorphan (DM) and IV lidocaine improve postoperative pain relief. In the present study, we evaluated the interaction of DM and IV lidocaine on pain management after laparoscopic cholecystectomy (LC). One-hundred ASA physical status I or II patients scheduled for LC were randomized into four equal groups to receive either: (a) chlorpheniramine maleate (CPM) intramuscular injection (IM) 20 mg and IV normal saline (N/S) (group C); (b) DM 40 mg IM and IV N/S (group DM); (c) CPM 20 mg IM and IV lidocaine 3 mg .