title: Meperidine and topical lidocaine in pre-endoscopic medication.
mesh_terms: D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D004724:Endoscopy; D006801:Humans; D008012:Lidocaine; D008614:Meperidine; D011292:Premedication
chemical_list: D008012:Lidocaine; D008614:Meperidine