Herbal medicine is the use of various parts of plants for medicinal purposes. All indigenous cultures in the world have used nature's substances (especially plants) to promote healing and alleviate pain. Herbal therapies are most commonly grounded in Western medicine approaches, Ayurvedic Medicine (the traditional medicine of India) and Traditional Chinese Medicine.
Research in herbal medicine is in a relatively early phase, and many studies have yielded only preliminary findings. Nevertheless, there is evidence that botanical medicines have established physiological effects or efficacy for clinical conditions, either alone or in combination with pharmaceuticals. Herbal approaches usually have been pursued because of the perception that many of these therapies are gentler and produce fewer side effects than pharmaceuticals. This perception must be tested in each case, however. It is important to remember that herbs contain active chemicals that may have side effects or interactions with foods and other drugs; some herbs are known to be unsafe in certain circumstances, such as pregnancy. The use of herbal therapies should be discussed with a health professional.
A number of herbal agents have established effects as pain relievers and anti-inflammatory drugs. Some are already integrated into conventional pain management programs.
Ginger extract may have a moderate positive effect
on osteoarthritis, with a good safety profile. Two studies have evaluated
a specific ginger extract (Eurovita Extract 33; EV ext-33) 170 mg three
times daily or 255 mg twice daily (510 mg total daily dose) for 3-6
weeks (Altman, 2001; Marcus 2001). Results indicate that ginger modestly
improved pain after standing or walking, and joint stiffness in some
patients. It does not seem to significantly improve overall functioning,
quality of life, or the level of use of analgesic medications. In another
study, no significant difference was observed between ginger, ibuprofen,
and placebo (Bliddal, 2000). In an overview of systematic reviews on
various herbal medicines for osteoarthritic and chronic low back pain,
the evidence of effectiveness was moderate for ginger (Chrubasik, 2007).
Willow bark includes flavonoids, tannins, and salicylates. It is the anti-inflammatory action of the salicylates (the active ingredient in aspirin is acetylsalicylic acid) that suggested willow bark's use for inflammatory pain. However, because of the time it takes to be metabolized and absorbed, willow bark has a slower onset and a longer duration than salicylate itself. There is some evidence that a willow bark extract providing 120-240 mg of the salicin constituent daily can reduce back pain in some patients (Chrubasik, 2000). The higher dose of salicin (240 mg---equivalent to only 50 mg of acetylsalicylic acid-aspirin) is more effective. A week or more is required to observe benefit. Willow bark extract also has a moderate pain relieving effect in osteoarthritis and appears to be well-tolerated (Schmid, 2001). The use of this herb should be avoided in people with aspirin hypersensitivity, asthma, active peptic ulcer disease, diabetes, gout, hemophilia, hypoprothrombinemia, and kidney or liver disease.
Capsaicin is the active ingredient in chili peppers. It has important effects on pain-sensitive nerves and has been used extensively by scientists studying pain pathways. There have been numerous studies of topically applied capsaicin, but there still is no definitive answer about its analgesic effects. Some studies suggest that it can be a useful agent for patients with various neuropathic pain syndromes, such as postherpetic neuralgia (shingles), postmastectomy pain and diabetic neuropathy; other studies suggest that it can be helpful in the treatment of joint pain caused by osteoarthritis (Fusco, 1997; Rains, 1995). There also is some evidence that it may be effective when used topically for fibromyalgia (McCarty, 1994).
Devil's Claw may be effective in osteoarthritis and chronic low back pain (Chrubasik, 1999, 2000). When taken in conjunction with a nonsteroidal anti-inflammatory drug for osteoarthritis, it may be able to reduce the dose required for benefit (Chantre, 2000). Although Devil's claw is generally well-tolerated, caution has been advised in patients with peptic ulcer disease, gallstones, diabetes and cardiovascular conditions such as hypertension. It is contraindicated in pregnancy.
Curcumin has been shown to have strong anti-inflammatory effects when tested in animals. Laboratory studies have shown that part of its mechanism of action is due to a natural COX-2 inhibiting effect. In one clinical study, curcumin was found to be as effective as cortisone for acute inflammation and half as effective for chronic inflammation (Mukhopadhyay, 1982). Studies have suggested benefit in osteoarthritis, rheumatoid arthritis, ulcerative colitis, and fibromyalgia (Ammon, 1993; Gupta, 1997; Sharma, 1989; Reddy, 1989). Curcumin has a good safety profile but is contraindicated in people with bile duct obstruction, gallstones, stomach ulcers or hyperacidity disorders.
Boswellia, one of many herbs used in Ayurvedic Medicine, comes from a tree found in India. The tree is a member of the frankincense family and contains a gummy resin that is purified into an herbal preparation. Laboratory studies have shown that boswellic acids inhibit inflammatory mediators, such as leukotrienes (Safayhi, 1992; Singh, 1986). They have an anti-inflammatory action similar to nonsteroidal anti-inflammatory drugs. One double-blind, placebo-controlled trial showed that boswellic acid-containing gum resin was effective in the treatment of bronchial asthma (Gupta, 1998). Data on its effectiveness for osteoarthritis and rheumatoid arthritis have been conflicting (Etzel, 1996; Sander, 1998). However, an oral combination product called Articulin-F(R) was shown to significantly improve symptoms of rheumatoid arthritis and osteoarthritis (Kulkarni 1992, 1991) and an extract of the gum resin provided symptomatic improvement in patients with ulcerative colitis (Gutpa, 1997).
Feverfew also inhibits the production of leukotrienes and the release of serotonin and histamine from platelets (Sumner, 1992). In a review of clinical studies on the use of feverfew for the treatment of migraine, four out of five studies suggested beneficial effects (Vogler, 1998). Taken as recommended, side effects, such as gastrointestinal upset and nervousness, are usually mild, and four to six weeks of use are required before benefits occur. The use of feverfew is strongly contraindicated during pregnancy, as it could cause uterine contractions or abortion (Farnsworth, 1975).
Some herbal therapies may have clinically important antidepressant or anti-anxiety effects.
St. John's wort has been studied in several controlled studies, and the results have been conflicting. Some studies suggest that it may be effective for mild to moderate depression (Whiskey, 2001; Kalb, 2001; Kim, 1999; Linde, 2000; Schrader, 2000; Brenner, 2000). It has relatively few side effects, but should be used cautiously by patients with Alzheimer's disease, bipolar disorder, major depression, or schizophrenia; these patients should be under the care of a mental health professional before starting treatment. It is also associated with some significant herb-drug interactions, which might lead to the reduced effectiveness of some medications, including chemotherapy and anti-HIV drugs.
Valerian is primarily used for insomnia but may also be effective in reducing anxiety. Clinical studies have suggested that it can be as effective as standard sleep medications and have very few side effects (Wheatley, 2001; Donath, 2000; Fugh-Berman, 1999). Significant improvement, however, can require two to four weeks of treatment.