The use of willow bark dates back to the time of Hippocrates (400 BC) when
patients were advised to chew on the bark to reduce fever and inflammation.
Willow bark has been used throughout the centuries in China and Europe, and
continues to be used by herbalists today for the treatment of fever, pain
(particularly low back pain), headache, and inflammatory conditions such as
arthritis. Although the bark of the white willow is most commonly used
medicinally, the bark of related species, such as black willow, have been shown
to have the same beneficial effects.
The willow family includes a number of different species of deciduous trees
and shrubs native to Europe, Asia, and some parts of North America. Some of the
more commonly known are white willow/European willow (Salix alba), black
willow/pussy willow (
Salix nigra), crack willow (Salix fragilis), purple willow
(Salix purpurea), and weeping willow (Salix babylonica). The
willow bark sold in Europe and the United States usually includes a combination
of the bark from white, purple, and crack willows.
Medicinal Uses and Indications
Willow bark's most important medicinal qualities are its ability to ease pain
and reduce inflammation. In fact, it was from salicylic acid, one of the
ingredients in willow bark, that aspirin was originally synthesized. Studies
have identified several other components of willow bark which have antioxidant,
fever-reducing, antiseptic, and immune-boosting effects.
Studies suggest that willow bark may be useful for the following
Headache Willow bark has been shown to relieve headaches and
some experts suggest that it may be preferable to certain conventional therapies
such as ibuprofen and other non-steroidal anti-inflammatories, which have been
linked to serious gastrointestinal side effects. Large-scale studies are
necessary to fully determine the safety and effectiveness of willow bark for
chronic or recurrent headaches, however.
Low Back Pain In a study of nearly 200 people with low back
pain, participants who received willow bark experienced a significant
improvement in pain compared to those who received placebo. Moreover,
participants who received higher doses of willow bark (240 mg salicin) had more
significant pain relief than those who received low doses (120 mg salicin).
Osteoarthritis In a small study of people with osteoarthritis
of the neck or lower back, those who received willow bark experienced
significant improvement in symptoms compared to those who received placebo. A
similar study of 78 patients hospitalized with osteoarthritis of the knee or hip
joint found that patients who received willow bark experienced significant pain
relief compared to those who received placebo.
Other Conditions Some professional herbalists may recommend
willow bark for the following conditions, although at present, no scientific
studies have been conducted to support these uses:
Mild diarrhea with cramps
Ankylosing spondylitis (a form of rheumatoid arthritis affecting the
Dosage and Administration
The use of willow bark in children has not been evaluated in well-designed
scientific studies. Some researchers speculate that the salicin in willow may
increase the risk for Reye's syndrome (a serious condition that affects the
liver and sometimes the brain and which is marked by recurrent vomiting).
Although there is no documented evidence that the herb can cause such a serious
condition, it is recommended that willow bark not be used by children with
flu-like symptoms, chickenpox, fever, or dehydration until conclusive evidence
shows that there is no risk.
General dosing guidelines for willow bark are as follows:
Dried herb (used to make tea): boil 1 to 2 tsp of dried bark in 8 oz
of water and simmer for 10 to 15 minutes; let steep for ½ hour; drink 3 to 4
Powdered herb (available in capsules): 1 to 3 g daily
Tincture (1:5, 30% alcohol): 4 to 6 mL three times per day
Standardized extract: tablets or liquid containing 60 to 240 mg of
salicin once a day
Because willow bark contains salicin, people who are allergic or sensitive to
salicylates (such as aspirin) should not use willow bark. Although the
scientific evidence is inconclusive, some researchers suggest that people with
asthma, diabetes, gout, gastritis, hemophilia, and stomach ulcers should also
avoid willow bark. If you have any of these conditions, be sure to consult your
healthcare provider before taking willow bark.
There is no evidence of adverse effects associated with willow bark. However,
side effects such as gastrointestinal irritation and ulcers are potentially
associated with all compounds containing salicylates. Overdoses of willow bark
may cause skin rash, stomach inflammation/irritation, nausea, vomiting, kidney
inflammation, and tinnitus (ringing in the ears).
Pregnancy and Breastfeeding
Salicyclates are not recommended during pregnancy, so it may be wise for
pregnant and breastfeeding women to avoid willow
Interactions and Depletions
Because willow bark contains salicylates, it has the potential to interact
with blood-thinning medications, such as aspirin and warfarin. People who are
taking anticoagulant or antiplatelet medications should avoid the use of willow
bark althogether, except under strict medical supervision.
Reviewed By: Participants in the review process include: Jacqueline A. Hart, MD,
Department of Internal Medicine, Newton-Wellesley Hospital, Harvard University
and Senior Medical Editor Integrative Medicine, Boston, MA; David Winston,
Herbalist, Herbalist and Alchemist, Inc., Washington, NJ; Tom Wolfe, P.AHG,
Smile Herb Shop, College Park, MD.
The publisher does not accept any responsibility for the accuracy of
the information or the consequences arising from the application, use, or misuse
of any of the information contained herein, including any injury and/or damage
to any person or property as a matter of product liability, negligence, or
otherwise. No warranty, expressed or implied, is made in regard to the contents
of this material. No claims or endorsements are made for any drugs or compounds
currently marketed or in investigative use. This material is not intended as a
guide to self-medication. The reader is advised to discuss the information
provided here with a doctor, pharmacist, nurse, or other authorized healthcare
practitioner and to check product information (including package inserts)
regarding dosage, precautions, warnings, interactions, and contraindications
before administering any drug, herb, or supplement discussed