Authors' objectives:

This study aims to assess the available evidence on the efficacy/effectiveness and safety of COX-2 inhibitors for the treatment of dysmenorrhea.

Authors' recommendations: Information was obtained from four randomized controlled trials, all of which were funded by pharmaceutical companies. The study population were mainly caucasian represented by women with a mean age range of 27 to 30 years with PD over three consecutive cycles. In one RCT, women received the same drug during three menstrual cycles while in the other trials each woman experienced each drug therapy once in a random sequence during one menstrual cycle. Women were allowed to take rescue medication for pain in all studies. The end points measured varied across studies, one study measured outcomes up to 24 hours after the drug was administrated and two studies measured outcomes only to 16 hours and 12 hours, respectively. COX-2 inhibitors administered were meloxican 7.5 mg and 15 mg (one RCT), etoricoxib 120 mg (one RCT), and lumiracoxib 400 mg (two RCTs) administrated in a single oral dose, or once daily as needed. Comparators were naproxen sodium, mefenamic acid, and placebo. None of the COX-2 selective inhibitors included in the RCTs have market approval from Health Canada. Meloxicam is approved but licensure approval is for other indications. The efficacy/effectiveness of COX-2 inhibitors was similar with the efficacy of non-selective NSAIDs, for the treatment of pelvic pain in women who suffer from primary dysmenorrhea (PD). The results indicated that lumiracoxib 400 mg administered once daily was not SS different compared with naproxen 500 mg twice daily. Also, etoricoxib 120 mg administered in a single dose was not statistically significant different compared with single dose of naproxen sodium 550 mg.30 Meloxicam doses of both 7.5 mg and 15 mg once daily showed the same efficacy/effectiveness when compared to mefenamic acid 500 mg three times a day. The authors reported a good tolerability of COX-2 selective inhibitors with few, but not serious AEs. However, the information provided was not detailed. The most frequent AEs noted were dyspepsia, diarrhea, gastritis, and vomiting in the RCT which compared mefenamic acid and meloxicam; and headache and nausea in the RCT that compared treatment with naproxen, placebo, and etoricoxib. The risk of developing gastrointestinal adverse effects (GI AEs) in the population of women with PD is expected to be lower due to the age of the women and the intermittent use of these drugs, over short periods of time. A systematic review published by the Cochrane collaboration group amended in 2003 concluded that non-selective NSAIDs were effective for treating dysmenorrhea. However, there was insufficient evidence to determine which standard NSAID was the most effective and which one had the best safety profile. The research evidence presented here indicates that COX-2 selective inhibitors are more effective than placebo for the treatment of primary dysmenorrhea and COX-2 selective inhibitors are as effective as non-selective NSAIDs. COX-2 selective inhibitors are currently under close scrutiny as rofecoxib (Vioxx (R)) and valdecoxib (Bextra (R)) were recently withdrawn from the market place due to the significant risk of cardiovascular events and life threatening skin reactions.

Authors' methods: Overview

Project Status: Completed

Year Published: 2005

URL for published report: https://www.ihe.ca/advanced-search?type=1020

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Canada

Organisation Name: Institute of Health Economics

Contact Address: 1200, 10405 Jasper Avenue, Edmonton, Alberta, Canada, T5J 3N4. Tel: +1 780 448 4881; Fax: +1 780 448 0018;

Contact Name: djuzwishin@ihe.ca

Contact Email: djuzwishin@ihe.ca

Copyright: <p>Alberta Heritage Foundation for Medical Research (AHFMR)</p>