RT Journal Article SR Electronic T1 The IPSO study: ibuprofen, paracetamol study in osteoarthritis. A randomised comparative clinical study comparing the efficacy and safety of ibuprofen and paracetamol analgesic treatment of osteoarthritis of the knee or hip JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 1028 OP 1034 DO 10.1136/ard.2003.011403 VO 63 IS 9 A1 F Boureau A1 H Schneid A1 N Zeghari A1 R Wall A1 P Bourgeois YR 2004 UL http://ard.bmj.com/content/63/9/1028.abstract AB Objective: To compare the analgesic efficacy of single and multiple doses of ibuprofen with that of paracetamol in patients with knee or hip osteoarthritis (IPSO study).Method: 222 patients were randomised in a double blind, multicentre study—156 (70%) had a painful knee joint and 66 (30%) a painful hip joint. The main efficacy criterion was pain intensity assessment after a single dose (ibuprofen 400 mg, paracetamol 1000 mg). Functional disability assessment and patient global assessment were carried out over 14 days.Results: The sum of the pain intensity difference over 6 hours after the first administration was significantly higher (p = 0.046) in the ibuprofen group than in the paracetamol group. Over 14 days pain intensity decreased from the first day and was significantly lower in the ibuprofen group than in the paracetamol group (p<0.05). The functional disability of the patient was assessed using the WOMAC; the ibuprofen group improved significantly over 2 weeks compared with the paracetamol group for each of the subscales: stiffness (p<0.002), pain (p<0.001), physical function (p<0.002). The drugs were equally safe.Conclusion: The IPSO study shows that for the treatment of osteoarthritic pain, ibuprofen 400 mg at a single and multiple dose (1200 mg/day) for 14 days is more effective than paracetamol, either as a single dose of 1000 mg or a multiple dose (3000 mg/day). Because ibuprofen and paracetamol have similar tolerability, this study indicates that the efficacy/tolerability ratio of ibuprofen is better than that of paracetamol in this indication over 14 days.