Diflunisal has an analgesic effect similar to other NSAIDs in single dose, but benefits from providing significant analgesia for about twelve hours. This property may be useful when regular dosing is needed, or when taking several doses of a shorter acting analgesic is impractical.
A 12-hour evaluation of the analgesic efficacy of diflunisal, zomepirac sodium, aspirin, and placebo in postoperative oral surgery pain.
One hundred ninety-nine outpatients with pain following oral surgery were randomly assigned, on a double-blind basis, a single oral dose of diflunisal (500 or 1,000 mg), zomepirac sodium 100 mg, aspirin 650 mg, or placebo. Using a self-rating record, subjects rated their pain and its relief hourly for 12 hours after medication. Measures of total and peak analgesia were derived from these patients' subjective reports. Diflunisal (500 and 1,000 mg) and zomepirac were significantly superior to aspirin and placebo for every measure of total and peak analgesia. Based upon the first 4 hours of observation, aspirin was superior to placebo for every measure of analgesia. Diflunisal 500 and 1,000 mg were comparable to zomepirac in peak analgesia and significantly superior to zomepirac for all measures of total analgesia. The onset of analgesia was comparable for 1,000 mg diflunisal, zomepirac, and aspirin, but more rapid for these treatments than for 500 mg diflunisal. The duration of analgesia was 12 hours for diflunisal, 9 hours for zomepirac, and 3 hours for aspirin.