Diphenhydramine as an adjunct to sedation for colonoscopy: a double-blind randomized, placebo-controlled study.

BACKGROUND: Intravenous benzodiazepines in combination with opiates are used to achieve moderate sedation for colonoscopy. Although effective, these agents have potential adverse effects, such as respiratory depression and hypotension. Diphenhydramine hydrochloride possesses central nervous system depressant effects that theoretically could provide a synergistic effect for sedating patients. OBJECTIVE: The objective was to assess the efficacy of adding diphenhydramine hydrochloride as an adjunct to improve sedation and to reduce the amount of standard sedatives used during colonoscopy. DESIGN: We conducted a prospective, randomized, double-blind, placebo-controlled study. SETTING: The study was conducted in a university hospital with an active GI fellowship training program. PATIENTS: The study group comprised 270 patients undergoing screening/diagnostic/therapeutic colonoscopy were enrolled. INTERVENTIONS: Patients were randomized to receive either 50 mg of diphenhydramine or placebo, given intravenously 3 minutes before starting conscious sedation with intravenous midazolam and meperidine. MAIN OUTCOME MEASUREMENTS: The main outcome measure was anesthetic effect as assessed by the endoscopy team and by the patient; quantity of adjunctive sedatives to achieve adequate sedation. RESULTS: Of 270 patients, data were analyzed for 258 patients, with 130 patients in the diphenhydramine group and 128 patients in the placebo group. There was a 10.1% reduction in meperidine usage and 13.7% reduction in midazolam usage in favor of the diphenhydramine group. The mean evaluation scores as judged by the faculty, the fellows, and the nurses were statistically significant in favor of the diphenhydramine group. In addition, patient scores for overall sedation and pain level favored the group that received diphenhydramine. CONCLUSIONS: Intravenous diphenhydramine given before initiation of standard sedation offers a significant benefit to conscious sedation for patients undergoing colonoscopy.

Endoscopic evidence of mucosal injury in patients taking ticlopidine compared with patients taking aspirin/nonsteroidal antiinflammatory drugs and controls.

BACKGROUND: Ticlopidine is a novel antiplatelet agent used alone or in combination with aspirin and anticoagulants in the treatment and prevention of various vascular diseases. Gastrointestinal side effects, including bleeding, have been reported with use of ticlopidine in most of the vascular prevention trials. We studied the endoscopic evidence of mucosal damage in patients taking ticlopidine compared with patients taking aspirin/nonsteroidal antiinflammatory drugs (NSAIDs) and matched controls. STUDY: We performed a longitudinal review of gastrointestinal endoscopy, pharmacy databases, and medical records of patients referred to our service over a period of 6 months for endoscopic evaluation of upper gastrointestinal bleeding, unexplained anemia, or abdominal pain. Data were collected and analyzed for 55 patients taking ticlopidine, 77 age- and gender-matched patients taking aspirin or NSAIDs, and 560 age- and gender-matched control patients not taking any of these medications. RESULTS: The overall prevalence of ulcers was marginally higher in the aspirin/NSAID group than in the ticlopidine group (35% vs. 29%) and was significantly higher among patients taking aspirin, NSAIDs, or ticlopidine than among controls (15%). Gastritis was also noted more frequently in the aspirin/NSAID and ticlopidine groups than in the control group. Endoscopic evidence of esophagitis was significantly more frequent in the control group than in the aspirin/NSAID and ticlopidine groups. There was no significant difference across groups in the prevalence of ulcers, gastritis, or esophagitis. CONCLUSIONS: Patients taking ticlopidine are more likely to have endoscopic evidence of mucosal damage than matched control patients and are nearly as likely to have such damage as endoscopically evaluated patients taking aspirin or NSAIDs. However, these findings must be confirmed using prospective cohort data for patients in primary care settings, to avoid referral bias.