One hundred-three patients with painful episodes of osteoarthritis of the knee were randomly assigned to receive, in double-blind fashion, an oral enzyme-flavonoid preparation (Phlogenzym; Mucos Pharma, Geretsried, Germany) or diclofenac sodium (50 mg twice a day) for 6 weeks. Each enteric-coated tablet of Phlogenzym contained 90 mg of bromelain, 48 mg of trypsin, and 100 mg of rutosid (a flavonoid similar to rutin); the dose was 1 tablet 3 times a day. The primary outcome variables were Lequesne's Algofunctional Index (LFI) and a "complaint index", including pain at rest, pain on motion and restricted function. Both treatments resulted in clear improvements. The mean value of the LFI decreased (improved) from 13.0 to 9.4 in the Phlogenzym group and from 12.5 to 9.4 in the diclofenac group. Significant improvements were also seen in the complaint index, with a slight tendency towards superiority of Phlogenzym. According to the physician's global judgment of efficacy, the results were rated as good or better for 51.4% of the Phlogenzym patients, and for 37.2% of the diclofenac patients. Most patients in each group rated tolerability very good or good.

Comment: The results of this study indicate that an oral enzyme-flavonoid combination was at least as effective as a standard non-steroidal anti-inflammatory drug (NSAID) in the treatment of osteoarthritis of the knee. While this product probably does not influence the progression of the disease (like glucosamine sulfate and chondroitin sulfate do), it appears to be useful for symptom relief. Given the currently available choices of rotting your heart with COX-2 inhibitors, rotting your intestines or kidneys with other NSAIDS, or rotting your liver with acetaminophen, it is encouraging to have a simple alternative that does not seem to rot anything.

Akhtar NM, et al. Oral enzyme combination versus diclofenac in the treatment of osteoarthritis of the knee - a double-blind prospective randomized study. Clin Rheumatol 2004;23:410-415.