The Median Effective Dose (ED50) of Paracetamol and Morphine : A Study of Interaction Study

Postoperative Pain Clinical Trial

Official title: The Median Effective Dose (ED50) of Paracetamol and Morphine for Postoperative Patients: A Study of Interaction.

Status Completed

Clinical Trial Summary

The aim of our study is to define the median effective analgesic doses (ED50) of paracetamol, morphine, and their combination and determination the nature of their interaction administered IV for postoperative pain after moderate painful surgery using up-and-down and isobolographic methods.

Clinical Trial Description

Ninety patients scheduled to undergo moderately painful surgery were included in one of three groups. Determination of median effective (ED50) doses was performed by the Dixon and Mood up-and-down method. Initial doses were 1.5g and 5mg, with dose adjustment intervals of 0.5g and 1 mg, in the paracetamol and morphine groups, respectively. The initial doses of paracetamol and morphine were 1.5g and 3mg, respectively in the paracetamol-morphine combination group with dose adjustment intervals of 0.25g for paracetamol and 0.5mg for morphine. Analgesic efficacy was defined as a decrease to less than 3 on a 0-10 numeric pain scale, 45 min after the beginning of drug administration. Isobolographic analysis was used to define the nature of their interaction. ;

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Pain, Postoperative
• Postoperative Pain

• NCT number: NCT01366313
• Study type: Interventional
• Source: Procare Riaya Hospital
• Status: Completed
• Phase: N/A
• Start date: September 2007
• Completion date: March 2011