Willow (Salix alba)

Willow (Salix alba) is a tall tree or dwarf shrub of the willow family (Salicaceae). Although it mostly sheds its leaves in winter, it is rarely an evergreen woody plant. It has been known in Anatolia since ancient times and is widely used in traditional medicine. Salicin, extracted from willow bark, is the active ingredient in the drug known as "aspirin".

Willow is rich in phenolic compounds such as flavonoids, tannins and salicylates. Pharmacological studies usually associated with salicylates apply to willow, supporting most herbal uses.

Several studies have shown that willow has anti-inflammatory, antirheumatic, antipyretic, analgesic, antiseptic and astringent properties due to the constituents it contains. Traditionally it has been used for inflammation and pain, influenza, respiratory catarrh, gouty arthritis and muscular and rheumatic conditions, particularly rheumatoid arthritis and conditions characterised by inflammatory changes. The German Commission E has approved internal use for diseases accompanied by fever, rheumatic disorders and headache.

Willow bark extract (equivalent to 240 mg salicin/day) was compared with placebo in a two-week, randomised, double-blind trial involving 78 patients with osteoarthritis. Significant differences in pain scores were observed in the treated group compared with the placebo group. The pharmacological effects of salicylates in humans are well documented and also apply to willow. Salicin is a precursor which is metabolised in the gastrointestinal tract to saligenin and, after absorption, to salicylic acid.