encyclopedia

Willow Bark

Scientific Names:
Salix alba L., S. purpurea L., S. daphnoides VILL., S. fragilis L. and other Salix species [Fam. Salicaceae]

Forms:
Bark and bark extract of willow tree species; willow bark tea.

Traditional Usage:
– Bone and Joint Pain
– Colds
– Fevers
– Flu
– Food Poisoning
– Gout
– Headache
– Osteoarthritis
– Pain
– Rheumatism
– Sprains
– Tendinitis
– Toothache Pain

Overview:
White willow, Salix alba L. [Fam. Salicaceae], also known as European willow, is a tree recognized for its medicinal bark containing natural ‘aspirin’ or salicin. The bark taken from the branches has pain-relieving (analgesic) and anti-inflammatory properties. A recent double-blind, randomized controlled trial with 78 patients over 2 weeks assessed the clinical efficacy of a standardized willow bark extract in the treatment of osteoarthritis (39 willow bark extract, 39 placebo) and concluded that willow bark extract had a good analgesic effect in osteoarthritis and appeared to be well tolerated. The dosage used was 240 mg salicin/day compared with placebo. After 2 weeks, the patients taking willow bark extract had a pain score that was reduced by 14% from the original level, compared with an increase of 2% in the placebo group. Patient diaries and overall assessments showed the significant superiority of the willow bark extract over placebo (patients’ assessment, p = 0.0002; investigators’ assessment, p = 0.0073). Willow bark was used in ancient Greek medicine and was first reported by Dioscorides in his De Materia Medica in the first century A.D. It was also used in Europe in the Middle Ages to reduce fevers and pain. Throughout Canada and the United States, First Nation’s people traditionally used willow barks of many different species extensively for relieving pain and reducing fever. The Cherokee use white willow bark tea to treat fever. The Blackfoot use pussy willow twigs (S. discolor) to treat pain and fever. The Iroquois use sandbar willow stems (S. interior) as a painkiller. Eskimos use tealeaf willow bark (S. planifolia) to treat pain. Other traditional uses of willow bark include for food poisoning, passive hemorrhages, chronic mucous discharges, diarrhea, worms and corns. Dr. James Duke also recommends it for heart disease, Alzheimer’s, backache, carpal tunnel syndrome, earache, and sciatica.

Active Ingredients:
White willow bark contains: Phenolic glycosides; salicin, picein and triandrin, with esters of salicylic acid and salicyl alcohol, acetylated salicin, salicortin and salireposide. Miscellaneous; tannins, catechin, p-coumaric acid and flavonoids. Note: White willow grows to a height of 30 to 80 feet, has large, spreading branches, and produces long flowers that appear from March to June. Other willow species used medicinally in the same way as Salix alba L. that have high salicin content include purple osier willow, S. purpurea L., common osier willow, S. daphnoides VILL. and crack willow, S. fragilis L.

Suggested Amount:
The daily dosage of willow bark corresponds to from 60 to 250 milligrams of the active ingredient, salicin. Tea: Place 2 to 3 grams (about 11/4 to 2 teaspoonfuls) of cut or powdered white willow bark in cold water, bring to a boil, steep for 5 minutes, then strain. Drink three to five times per day. The German Commission E recommends using the bark of 2-3 year old branches.

Drug Interactions:
Drug interactions similar to those seen with aspirin and other salicylates may arise. However, studies conducted thus far do not indicate this potential toxicity for willow bark.

Contraindications:
Aspirin is contraindicated in young children suffering from flu for fear that it may cause Reyes syndrome, and some herbalists also recommend against using willow bark in young children for the same reason. However, the salicylates in willow metabolize differently than aspirin (acetylsalicylic acid).

Side Effects:
Aspirin causes an increased risk of stomach ulcers and other stomach problems, however, studies conducted thus far on willow bark do not indicate this potential toxicity.

References:

Blumenthal M, Goldberg A, Brinckmann J 2000. Herbal Medicine: Expanded Commission E Monographs. Copyright American Botanical Council. Publ. by Integrative Medicine Communications, 1029 Chestnut Street, Newton, MA 02464. Pp. 408-412.

Duke, J. 1997: The Green Pharmacy, The Ultimate Compendium of Natural Remedies from the World’s Foremost Authority on Healing and Herbs. pp. 18; 36; 299; 499-500; 511; 50; 57; 73-74; 91-92; 126; 132; 152; 170-171; 178; 217; 240-242; 275; 281-2; 286; 422-3; 466; 132; 518; 549. Rodale Press.

Schmid B, Ludtke R, Selbmann HK, Kotter I, Tschirdewahn B, Schaffner W, Heide L. 2001. Efficacy and tolerability of a standardized willow bark extract in patients with osteoarthritis: randomized placebo-controlled, double blind clinical trial. Phytother Res. 2001 Jun; 15(4): 344-50.

Wichtl M (ed). 1994. Salicis cortex – Willow bark. In Herbal Drugs and Phyto-pharmaceuticals. (English translation by Norman Grainger Bisset). CRC Press, Stuttgart, pp. 437-439.