Treatment of suspected symptomatic cholelithiasis with glycopyrrolate: A prospective, randomized clinical trial

Glycopyrrolate is advocated for the treatment of acute pain from suspected symptomatic cholelithiasis. However, there is no clinical evidence to substantiate its use. This study is designed to evaluate the efficacy of glycopyrrolate in relieving acute abdominal pain of suspected biliary tract origin. Between July 2002 and April 2003, a convenience sample of patients presenting to the emergency department with upper abdominal pain of suspected biliary tract origin was randomized to receive either intravenous glycopyrrolate or placebo (normal saline solution). Pain level was assessed at baseline using a visual analog scale, with a repeat assessment 20 minutes after intervention. Patients and clinicians were blinded to the study drug. Because of difficulty with patient enrollment, the trial was terminated before achievement of the initial goal of 54 patients. On analysis of the 38 patients completing the study protocol, glycopyrrolate and placebo groups had similar demographic and baseline characteristics. There was no significant difference in pain relief between patients receiving glycopyrrolate and those receiving placebo (median decrease in visual analog pain scale pain 3 mm [95% confidence interval −2 to 17 mm] versus 8 mm [95% confidence interval −2 to 20 mm], respectively). Although limited by small size and convenience sampling, these results fail to demonstrate any improvement in pain of suspected biliary tract origin with the administration of glycopyrrolate. Further study is needed to determine whether intravenous glycopyrrolate has any significant analgesic effect for patients with this condition.