A double-blind placebo controlled trial of oral midazolam as premedication before flexible sigmoidoscopy

Am J Gastroenterol. 1999 Nov;94(11):3215-9. doi: 10.1111/j.1572-0241.1999.01521.x.


Objective: We aimed to determine the efficacy of oral midazolam as premedication to improve tolerance of flexible sigmoidoscopy.

Methods: Ninety-nine patients were randomized to receive 7.5 mg of oral midazolam solution mixed with apple juice or placebo (apple juice), 20 min before sigmoidoscopy. Patients' anxiety and pain experienced before sedation, before the procedure, and during the procedure were assessed using a 10-cm visual analog scale (VAS) by both patients and physicians (0 = no pain, anxiety, 10 = severe pain, anxiety). Extent of sedation, amnesia, overall tolerance, adequacy of sedation, and willingness to repeat the procedure were assessed, and changes in vital signs and oximetries were recorded.

Results: Fifty-one patients received midazolam and 48 patients received placebo. Patients reported less pain and anxiety (VAS 2.56, 1.64) compared with placebo (VAS 4.62, 4.16) during the procedure (p < 0.005, p < 0.0005). Physicians observed less pain and anxiety (VAS 2.19, 1.52) with midazolam than placebo (VAS 5.00, 3.97) during the procedure (p < 0.0001, p < 0.0001). A significantly greater number of patients judged tolerance of the procedure to be "excellent" using midazolam (p < 0.005) compared with placebo. A majority of patients in both groups was willing to repeat the procedure if recommended. Two patients in the midazolam group had transient asymptomatic hypotension during sigmoidoscopy, but no patients were observed to have desaturation by oximetry.

Conclusions: Oral midazolam significantly reduces anxiety and pain during flexible sigmoidoscopy as assessed by both patients and physicians. Oral midazolam is a safe and effective premedication before flexible sigmoidoscopy in patients who require or prefer sedation.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Anxiety / prevention & control
  • Blood Pressure / drug effects
  • Double-Blind Method
  • Female
  • Humans
  • Hypnotics and Sedatives / administration & dosage
  • Hypnotics and Sedatives / adverse effects
  • Hypnotics and Sedatives / therapeutic use*
  • Hypotension / chemically induced
  • Male
  • Memory / drug effects
  • Midazolam / administration & dosage
  • Midazolam / adverse effects
  • Midazolam / therapeutic use*
  • Middle Aged
  • Oxygen / blood
  • Pain / prevention & control
  • Pain Measurement
  • Patient Satisfaction
  • Placebos
  • Premedication*
  • Safety
  • Sigmoidoscopy*


  • Hypnotics and Sedatives
  • Placebos
  • Midazolam
  • Oxygen