Willow bark comes from the willow tree family, which comprises several deciduous tree species and shrubs native to Europe, Asia and parts of North America. The bark (particularly white willow) gets used often in medicine and is sold in the U.S. and Europe in combination with purple and crack willow, which are more potent than the white version.
The willow bark herb's use for treatment goes far back into the history of China and Europe. By chewing on the bark, people could treat symptoms of pain and fever. The Greek physician Hippocrates, advised the use of the bark as a remedy to treat childbirth pain in the fifth century B.C. The company behind Bayer even developed aspirin in the 1890s using an active ingredient in willow bark called salicin.
Since willow bark acts very similarly to aspirin, people use it for pain (especially lower back pain), headaches and osteoarthritis and numerous scientific studies have confirmed the herb's ability to relieve those conditions. Research has also studied the effects of willow bark treatment on other conditions such as menstrual cramps, cold and flu, gout, inflammatory conditions (like tendinitis), rheumatoid arthritis and weight loss (when combined with other herbs), but those studies have provided insufficient evidence that the herb is significantly effective. Still, natural remedy seekers have been known to use willow bark in the attempt to treat those ailments, as well.
Form and Dosage
Only those over the age of 16 should take the willow bark herb. It comes in several forms: as a dried herb (used for making tea), in a liquid or powder form (in a capsule) or as a tincture.
You can prepare the dried herb a couple of ways. First, boil one to two teaspoons in cup of water, let simmer for up to 15 minutes, steep for half an hour, and drink a cupful three to four times a day. Or brew the herb in cold water for eight hours and strain away most of the salicin in the bark to provide the equivalent of a low dose of aspirin, 60 to 150 mg. Either way, the tea has a bitter taste to it, so you may want to add a sweetener.
Back pain sufferers prefer to take the capsule form, which provides 60 to 240mg of salicin a day. As for the tincture, you should take four to six mL three times a day.
Side Effects & Warnings
Only use willow bark short-term; otherwise, it can cause stomach irritation or inflammation, vomiting and nausea, itching, skin rash and tinnitus. It can lead to kidney failure by reducing blood flow to the kidneys. It also has chemicals that can have harmful effects on nursing infants through breast milk.
Don't take the herb two weeks before a surgery, as it may cause extra bleeding during and after the procedure. It may also cause slow blood clotting, so anyone taking blood-thinners should avoid it. People allergic to aspirin should avoid it as well. Children taking willow bark, especially those infected with viral conditions such as the cold or flu, increase the risk of developing Reye's syndrome, a rare disease that affects the brain and liver and can lead death.
Willow bark goes by several other common names. Weeping willow, basket willow, violet willow, white willow, organic willow, laurel willow and black willow are just some. You may also come across the names knackweide, lorbeerweide, osier rouge, purpurweide, reifweide, purple osier, weidenrinde and silberweide.