Diflunisal in the management of sprains

Diflunisal: a review of its pharmacological properties and therapeutic use in pain and musculoskeletal strains and sprains and pain in osteoarthritis

Diflunisal is a salicylic acid derivative with analgesic and anti-inflammatory activity. It has been studied in osteoarthritis, pain resulting from musculoskeketal sprains and strains and from minor surgery and cancer. The duration of its analgesic effect is longer than that of aspirin and diflunisal is effective when given twice daily. Diflunisal is not metabolised to salicylic acid and has a lesser effect than aspirin on platelet function in vivo. In osteoarthritis, diflunisal appears comparable in efficacy to moderate doses of aspirin (2 to 3g daily), but is better tolerated. It has not been compared with the most active phenylalkanoic acid derivatives such as naproxen in adequate numbers of patients. Diflunisal is comparable with glafenine in pain and with propoxyphene/paracetamol combinations and oxyphenbutazone in pain and in musculoskeletal strains and sprains. As with other non-steroidal agents, gastrointestinal complaints are the most frequently reported side effects.

Single-blind study of diflunisal versus mefenamic acid in the treatment of pain after Colles' fracture

A single-blind study was carried out in 52 patients with severe pain after Colles' fracture to assess the analgesic efficacy and tolerability of 500 mg diflunisal twice daily compared with that of 500 mg mefenamic acid given 3-times daily over a period of 5 days. The results showed that both treatments were effective in relieving pain, night pain and limitation of movement by pain, and there was no significant difference between the response in the two groups. Both drugs were tolerated and only 3 patients (2 on diflunisal) reported mild drug-related side-effects.

Post-operative analgesia with diflunisal

An open study was carried out in 196 consecutive patients who had undergone orthopaedic (103) or gynaecological (93) surgical procedures to assess the effectiveness and tolerability of a single dose of 500 mg diflunisal in the relief of postoperative pain. Diflunisal was given when patients first complained of pain, and pain severity before and at intervals up to 6 hours after the dose was assessed using a 10-point analogue scale. The results showed that diflunisal was both prompt and prolonged in its effect. No pain was reported after 1 hour in 138 (71%) of the 196 patients, and after 6 hours only 13 (7%) still reported some pain. Diflunisal was equally as effective in the two groups. Side-effects were reported in 13 (7%) patients but these were ones commonly found in the post-operative situation.