Willow

Deciduous trees from the willow family (Salicaceae), of which there are around 450 species. Trees grow up to 30 m high. The leaves of willows are round or narrow to lanceolate. Tree willows rarely reach an age of > 80 years.

The best known are the silver willow and the lower, multi-branched willow (willow catkins), as well as the weeping willow.

The dried willow bark(Salicis cortex) of young twigs in their 2nd or 3rd year is used phytotherapeutically. The bark of the willow contains salicyl alcohol derivatives(salicylates), caffeic acid derivatives and flavonoids. Willow species whose bark contains at least 1.5 % salicin are authorized.

HMPC monograph: As a quantified herbal preparation in solid dosage form: Well-established use: Low back pain, dosage: see finished product instructions, 393 mg-786 mg twice/day, not suitable for children and adolescents under 18 years of age. Traditional use: mild joint pain. Fever in colds, headaches.
ESCOP monograph: mild back pain, mild rheumatic complaints; feverish colds, headaches.
Commission e-monograph: febrile illnesses, rheumatic complaints, headaches.

Contraindication: Hypersensitivity to the active substance, to salicylates or other NSAIDs (e.g. angioedema, bronchial spasm or chronic urticaria as a reaction to salicylates or other NSAIDs in the past). Asthma with sensitivity to salicylates. Active gastric ulcers.

Glucose-6-phosphate dehydrogenase deficiency, children and adolescents under 18 years of age(Reye's syndrome), severe liver or kidney dysfunction. Coagulation disorders.

Not recommended in the first two trimesters of pregnancy due to lack of data, contraindicated in the third trimester.

The bark of the willows can be dried and brewed as tea. The extracts are now known as "vegetable aspirin". They contain tanning agents, phenol glycosides, salicin and acylated salicin derivatives. Salicin in particular is metabolised in the body to salicylic acid. Salicylic acid has antipyretic, pain-relieving and anti-rheumatic effects (see intolerance reaction) and in appropriate concentrations, when applied locally in adapted bases, it has antiseptic and keratolytic effects (see various formulations under salicylic acid).

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