Analgesia for outpatient surgery: placebo versus naproxen sodium (a non-steroidal anti-inflammatory drug) given before or after surgery.

One hundred and eighty patients scheduled for day-care surgery were allocated randomly to one of three groups to receive naproxen sodium 1100 mg 1 h prior to surgery, naproxen sodium 1100 mg immediately after surgery, or placebo. The pre-surgery naproxen sodium group had significantly lower pain scores 1 h post-operatively and at discharge than the placebo group. At discharge both treatment groups were better than placebo. At 24 h post-operatively only the post-operative naproxen sodium group had lower pain scores. There was no difference in post-operative analgesic requirements until discharge between the groups, but at 24 h post-operatively the placebo group had required significantly more analgesics than the treatment groups. A questionnaire concerning general acceptability of anaesthesia/analgesia showed similar results. Our conclusion is that naproxen is better than placebo for treatment of post-operative pain. The time of administration pre- or post-operatively is important for the immediate post-operative pain, but we found no support for the existence of 'pre-emptive analgesia'.