There is also interest in bromelain for the treatment of osteoarthritis. The proposed mechanism of action is similar to that of other nonsteroidal anti-inflammatory drugs. Taken orally, bromelain acts to block prostaglandin synthesis, thereby reducing the nociceptive perception of pain.3 Another immune-modulatory effect of bromelain is its ability to alter the cellular adhesion of lymphocytes.4,5 In a double-blind randomized study, 103 participants with confirmed osteoarthritis of the knee were treated for 6 weeks with either oral diclofenac or a combination containing bromelain.3 Patient performance was graded by the Lequesne Algofunctional Index and by subjective complaint index.3,6 At the end of the trial, researchers found that the enzymatic compound was as effective as standard diclofenac. 

Bromelain is also considered for its possible antitumoral effects, which are thought to be related to the same pathways as its anti-inflammatory and immune-modulating effects. In vitro studies of bromelain’s action on cultures of cancerous human cell lines have been conducted.7

Safety, interactions

There have been no phase 2 clinical trials in the United States of bromelain, but adverse events reported in human trials to date were usually mild and were resolved by lowering the dose or discontinuing treatment.8

Anyone allergic to pineapple should not receive bromelain therapy. Because of its anti-inflammatory action, bromelain can interact with blood clotting by interfering with the action of fibrin.8

How supplied, dose, cost 

Human clinical trials to ascertain the optimal dose of bromelain, especially in inflammatory arthritis, have shown efficacy beginning at as little as 160 mg/day.9 Although higher doses are used frequently, the incidence of side effects appears to be dose-dependent, with more frequent reports of adverse effects at higher dose ranges. 

Bromelain is available in tablets or capsules, and the cost is as little as $5 per month for the low- to mid-dose ranges.

This article originally appeared on Clinical Advisor