Clinical effects of Zingiber cassumunar (Plai): A systematic review.

Zingiber cassumunar Roxb. known locally as "Plai" in Thai, has been used for treating bruise, sprain and musculoskeletal pain. Several pre-clinical studies demonstrated the anti-inflammatory effect of Plai. However, current evidence of clinical effects of Plai is still unclear. This study aimed to determine the clinical efficacy and safety of Plai among all identified indications. Of the 808 articles identified by a systematic review, six studies were included. Four studies were randomized controlled trials, while two studies were quasi-experimental studies involving 178 patients in intervention group and 177 patients in control group. Duration of treatment ranged from 7days to 2 months. Our findings showed that 14% Plai cream had a strong trend of benefits in pain reduction for muscle pain and ankle sprain. However, evidence supporting the effects of Plai on acne vulgaris treatment and anti-histamine effect are still unclear.