AbstractThe pain-relieving efficacy of naproxen and acetylsalicylic acid (ASA) in tonsillectomized patients was compared in a double blind parallel clinical trial comprising 83 patients, among whom 42 were treated with naproxen and 41 with ASA. The patients were treated post-operatively for two days with either naproxen suppositories 500 mg. twice, or ASA effervescent tablets 1000 mg. three times, daily.The therapeutic gain was evaluated by recording the intensity of pain, reduced ability to open the mouth (trismus), consumption of supplementary analgesic (parcetamol), and pain-related sleep disturbances.The statistical analysis of the results revealed no differences in pain intensity, consumption of additional analgesics or pain-related sleep disturbances in the two treatment groups. A considerable degree of trismus was demonstrated in most of the tonsillectomized patients. This reduced ability to open the mouth was gradually overcome in the naproxen group while it remained unchanged in the ASA group, however, no statistical significant difference could be demonstrated. Additionally, no significant positive correlation between pain intensity and trismus was proven. The pain-relieving effect, however, was unsatisfactory in both the naproxen and the ASA group, and clinical controlled trial studies of alternative analgetics in tonsillectomized patients are still to be encouraged.