Symptom → Plant Sources
Willow Bark (Salix alba) as a tool for helping with Pain (general)
Analgesic and anti-inflammatory for low back pain (moderate evidence; dose-dependent, around 240 mg salicin/day) - in an RCT, 240 mg salicin/day left 39% pain-free vs 6% on placebo within 4 weeks; Relief of joint pain, osteoarthritis and rheumatic complaints
Since ancient times preparations from Salix species have been used to alleviate pain. The aim of this study was to update the evidence of the effectiveness of willow bark products in the treatment of musculoskeletal pain. OVID(MEDLINE), PUBMED, Silverplatter, and CENTRAL and manual searches were used to identify clinical trials investigating Salix preparations. Authors SC and JEV extracted the data independently and discussed disagreements. Seven manuscripts were identified, reporting four trials with confirmatory and four with exploratory study designs. Three manuscripts presented the same trial data: repetitious reports were excluded. One confirmatory and two exploratory studies indicate a dose-dependent analgesic effect not inferior to rofecoxib in patients with low back pain. In one exploratory and one confirmatory study conflicting results were achieved in participants with osteoarthritis. No significant effect was seen in a confirmatory study in patients with rheumatoid arthritis, but this study was grossly underpowered. All studies investigated ethanolic extracts with daily doses up to 240 mg salicin over periods of up to six weeks. Minor adverse events occurred during treatment. The review provides moderate evidence of effectiveness for the use of ethanolic willow bark extract in low back pain. Further studies are required to find out if treatment of osteoarthritis and rheumatoid arthritis requires extract with higher doses than 240 mg salicin per day.
This Cochrane review found moderate evidence that Salix alba (white willow bark), standardized to 120 mg or 240 mg salicin daily, was better than placebo for short-term improvements in low-back pain and reduced rescue medication, with one trial showing equivalence to rofecoxib.
Purpose Herbal medicines are widely used for the treatment of pain, although there is not much information on their effectiveness. This study was designed to evaluate the effectiveness of willow (Salix) bark extract, which is widely used in Europe, for the treatment of low back pain. Subjects and methods We enrolled 210 patients with an exacerbation of chronic low back pain who reported current pain of 5 or more (out of 10) on a visual analog scale. They were randomly assigned to receive an oral willow bark extract with either 120 mg (low dose) or 240 mg (high dose) of salicin, or placebo, with tramadol as the sole rescue medication, in a 4-week blinded trial. The principal outcome measure was the proportion of patients who were pain-free without tramadol for at least 5 days during the final week of the study. Results The treatment and placebo groups were similar at baseline in 114 of 120 clinical features. A total of 191 patients completed the study. The numbers of pain-free patients in the last week of treatment were 27 (39%) of 65 in the group receiving high-dose extract, 15 (21%) of 67 in the group receiving low-dose extract, and 4 (6%) of 59 in the placebo group (P Conclusion Willow bark extract may be a useful and safe treatment for low back pain.
4 sources supporting Willow Bark for Pain (general). Includes scientific publications, books, monographs and traditional-use references.
Mechanistic basis
This use is associated with the plant's analgesic (pain relief) action. Further evidence for that pharmacology:
This review of white willow bark (Salix alba) extracts summarises the evidence for its anti-inflammatory, antipyretic and analgesic activities (in chronic low-back and joint pain and osteoarthritis), its salicin and polyphenol constituents, and its favourable safety profile versus NSAIDs.
This updated Cochrane review concluded that daily doses of Salix alba (white willow bark) standardized to 120 mg or 240 mg salicin are probably better than placebo for short-term improvements in low-back pain and rescue medication (moderate-quality evidence).