While both B. sacra and B. serrata have been used medicinally, B. serrata is the species currently most used in herbal medicine and upon which all the modern clinical research has been done. Its main known pharmacologically-active constituents include α and β boswellic acid and other pentacyclic triterpenic acids shown in laboratory studies to inhibit inflammatory processes.19 Boswellic acids in proprietary formulations (e.g., 5-Loxin®) have demonstrated a high safety profile.20
A 2010 randomized, double-blind, split-face, comparative study was done to assess the efficacy, tolerability, and safety of a base cream containing 0.5% boswellic acids (BAs) (manufacturer unspecified) and the same cream without the BAs with regard to its use in treating photoaging of facial skin.21 Fifteen female volunteers applied the creams once daily for 30 days. The treatment was well tolerated and significant improvement occurred in tactile roughness and fine lines in the side of the face treated with the cream with BAs.
In 2008, a double-blind, randomized, placebo-controlled study examined 5-Loxin (30% 3-O-acetyl-11-keto-beta-boswellic acid [AKBA], P.L. Thomas and Co., Morristown, NJ) for treatment of osteoarthritis (OA) of the knee.22 For 90 days, 75 patients received either 100 mg or 25 mg daily of 5-Loxin or placebo. Each patient was evaluated at baseline and at days 7, 30, 60, and 90. At the end of the study, both doses of 5-Loxin showed clinically and statistically significant improvements in pain and physical function scores.