Acetylsalicylic acid, aspirin, Assalix®, Assplant®, basket willow, bay willow, beta-salicin, black willow, brittle willow, cadmium, caffeic acid, crack willow, daphne willow, ecorce de saule (French), ferulic acid, flavonoids, fragilin, glycosides, isosalicin, isosalipurposide, knackweide, laurel willow, lorbeerweide, osier rouge, picein, populin, purple osier, purple osier willow, purple willow, purpurweide, reifweide, rheumakaps, Salicaceae (family), salice (Italian), salicin, salicis cortex, salicortin, salicoylsalicin, salicyl alcohol, salicylate, salicylic acid, salicyluric acid, salidroside, saligenin, salipurposide, Salix alba, Salix daphnoides, Salix fragilis L., Salix pentandra, Salix purpurea L., sauce (Spanish), syringin, tannins, tremulacin, triandrin, vanillin, violet willow, Weidenrinde (German), white willow, white willow bark, willow, willow tree, willowbark, willowprin.
Note: This review covers salicin-containing species of Salix, which includes Salix alba, Salix fragilis, Salix purpurea, and Salix pentandra.
In the United States, willow bark is used by herbalists as an antipyretic (fever reducer), a mild analgesic (pain reliever), and an anti-inflammatory. There is currently strong scientific evidence that willow bark is effective for osteoarthritis and lower back pain. Early study suggests that willow bark extracts may not be helpful for rheumatoid arthritis, but further study is warranted to confirm these recommendations. Taking willow bark may increase the risk of bleeding; however, this risk may be less than taking aspirin.
Several countries in Europe have approved willow bark for pain and inflammatory disorders. The German Commission E has approved willow bark for fever, rheumatic ailments, and headaches. The British Herbal Compendium indicates that willow bark can be used for rheumatic and arthritic conditions, and fever associated with cold and influenza. In France, willow bark has been approved as an analgesic to treat headache and toothache pain, as well as painful articular (joint) conditions, tendonitis, and sprains. The European Scientific Cooperative on Phytotherapy (ESCOP) has approved willow bark extract for the treatment of fever, pain, and mild rheumatic complaints.
Willow bark is a traditional analgesic (pain relieving) therapy for osteoarthritis. Several studied have confirmed this finding. Additional study comparing willow bark to conventional medicinal agents for safety and effectiveness is warranted.
Lower back pain:
White willow has been compared to placebo and to cyclooxygenase-2 inhibitors, and many of the studies found willow bark to be as effective or superior to other methods. Cost effectiveness studies have also been performed between white willow bark and conventional treatment, and found that willow bark was more cost effective. Additional study would help make a strong recommendation.
Willow bark has traditionally been used to treat an array of inflammatory conditions, including headache. One study investigated a salicin topical cream for the treatment and/or prevention of migraine and tension-type headache. Although early study is promising, additional study is needed to draw a firm recommendation.
There is good evidence that willow bark may be effective in treating chronic pain from osteoarthritis; however, willow bark extract did not show efficacy in treating rheumatoid arthritis. Additional study is needed to make a firm recommendation.