Efficacy and safety of topical Matricaria chamomilla L. (chamomile) oil for knee osteoarthritis: A randomized controlled clinical trial.

OBJECTIVE To assess the efficacy and safety of topical Matricaria chamomilla (Chamomile) oil in patients with knee osteoarthritis. METHOD Patients were randomized and treated with topical chamomile oil, diclofenac or placebo, 3 times/day for 3 weeks. They were allowed to use acetaminophen as analgesic. The patients were asked about their total acetaminophen use. Moreover, they were assessed in the terms of pain, physical function and stiffness by using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire at the enrolling and weekly. RESULTS Chamomile oil significantly reduced the patients' need for acetaminophen (P = 0.001) compared with diclofenac and placebo. However, there were no significant differences in WOMAC questionnaire domains. The patients did not report any adverse events by using chamomile oil. CONCLUSION Chamomile oil decreased the analgesic demand of patients with knee osteoarthritis. In addition, it may show some beneficial effects on physical function, and stiffness of the patients.