The efficacy of topical red clover oil on knee osteoarthritis: A pilot prospective randomized triple‐blind placebo‐controlled clinical trial

Abstract A triple‐blind placebo‐controlled clinical trial was performed to evaluate the efficacy of topical red clover oil (containing standardized red clover extract in olive oil) on knee osteoarthritis (OA). A total of 80 patients, 50–80 years old, with primary knee OA were randomly allocated to two groups. The study group used topical red clover oil and the control group used olive oil for 4 weeks (20 drops twice a day). Both groups adhered to nonpharmacological American College of Rheumatology recommendations and took meloxicam tablets during the study (0–8 weeks), and were followed up from Week 4 to 8. Efficacy measures were evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale and Visual Analogue Scale (VAS). At baseline, both groups were homogeneous regarding demographic characteristics. In addition, they were asked about the side effects during the intervention. The results showed that the WOMAC score and its subscales of pain and stiffness and function scores and VAS significantly increased over time in both groups ( p < .001). The study group showed a significant increase regarding pain ( p = .001), function ( p = .010), VAS ( p < .001), and the WOMAC total score ( p = .018). No serious drug side effects were observed. Red clover oil may have positive effects on symptoms of knee OA and can be considered as a complementary treatment.