The analgesic and antiinflammatory activity and pharmacologic properties of bromfenac.

Bromfenac sodium (2-amino-3-(4-bromobenzoyl)benzeneacetic acid sodium salt sesquihydrate, AHR-10282B) is a potent long-acting, peripheral, analgesic compound possessing antiinflammatory, antipyretic, and prostaglandin synthetase-inhibiting properties. In the acetylcholine abdominal constriction assay in mice, bromfenac (bromfenac sodium) by the oral route at pretreatment times of 10, 20 and 300 min was respectively 3.7, 6.5 and 2.9 times more potent than zomepirac and 3.4, 6.6., and 44.2 times more potent than suprofen. In dogs bromfenac when given orally was 5.8 times more potent than zomepirac in blocking the nociceptive response to bradykinin. Naloxone did not alter the analgesic properties of bromfenac in mice; and after repeated administration, tolerance to analgesia did not develop. Bromfenac, given orally, was more potent than indometacin in suppressing acute (7.5-20 times) and chronic (3.8 times) inflammation. The gastric and intestinal toxicity potencies of bromfenac, given orally, were comparable with and 1.8 times more potent than indometacin, respectively. Bromfenac was 6.1 to 32.8 times more potent than indometacin in inhibiting the formation of prostaglandin E2 and F2 alpha from microsomes of bovine seminal vesicles, rabbit uteri, and rabbit renal medullae; but it did not block the direct action of prostaglandin E1 (abdominal constriction) and prostaglandin F2 alpha (contraction of the uterus). Bromfenac produced no unwanted central nervous system, cardiovascular, or autonomic effects.