Background: Although some patients can tolerate colonoscopy procedure using fentanyl/ midazolam without any sedation and analgesic requirements but some patients may require additional sedation with benzodiazepines. We performed the present study to compare the effect of paracetamol/midazolam with fentanyl/ midazolam.

 Methods: In a clinical trial, 96 patients aged 18 to 75 years old, who were candidate for elective colonoscopy assigned consecutively into two groups as paracetamol/midazolam and fentanyl/midazolam. The first group received 1 gr paracetamol 45 minutes before colonoscopy and 0.5 mg/kg midazolam 5 minutes before colonoscopy whereas the second group received 04- 0.5-1 mcg/kg fentanyl 3 minutes before colonoscopy and similar dose of midazolam. The two groups were compared in regard to patient intensity, discomfort, a colonoscopist and, patient satisfaction and rescue dose of propofol during colonoscopy and vital signs.

 Results: There was no significant difference between the two groups for patient pain score, colonoscopist satisfaction, patient satisfaction and rescue dose of propofol (P=0.817, 0.978, 0.460, and 0.104, respectively). The incidence of apnea was greater in fentanyl group (P=0.045). After adjusting for age and education, there was also no significant difference between the two groups.

 Conclusion: This study indicates that paracetamol can be considered as an alternative drug regimen in preparation of colonoscopy.