A total of seven RCTs were included in this review (n=421), with sample sizes ranging from 30 to 102. Five were placebo controlled RCTs and two trials were comparisons with alternative active interventions. The methodological quality was variable but three trials scored the maximum possible on the Jadad scale.
Boswellia extracts showed some positive results in the treatment of asthma (1 trial versus placebo, n=80), Crohn's disease (1 trial versus mesalazine, n=102), knee osteoarthritis (2 trials versus placebo and 1 trial versus valdecoxib, n=96) and collagenous colitis (1 trial versus placebo, n=31).
One study reported no significant difference between Boswellia and placebo in patients with rheumatoid arthritis (n=37).
Adverse effects were minor and judged as not causally related to the treatment.