Chronic Pain

Vitamins That Relieve Pain

Vitamin B1 (thiamin) and benfotiamine. Some animal studies have shown a decrease in pain with a combination of vitamin B1, vitamin B6, and vitamin B12 (Franca DS et al 2001; Jurna I 1998; Wang ZB et al 2005). The fat-soluble form of vitamin B1, called benfotiamine, has been used effectively to treat alcoholic and diabetic neuropathies. The most marked pain relief from benfotiamine occurred in patients with diabetic neuropathy after only a 3-week trial period (Anisimova EI et al 2001; Haupt E et al 2005; Winkler G et al 1999).

Niacin. Niacin has been shown to increase joint mobility and decrease joint pain (Jonas WB et al 1996). Fifty years ago, researchers reported that high-dose niacinamide was beneficial in the treatment of osteoarthritis and rheumatoid arthritis (Kaufman W 1955). A more recent double-blind study confirms the efficacy of niacinamide in treating osteoarthritis (Jonas WB et al 1996).

Vitamin B6 (pyridoxine). Studies show that vitamin B6 is effective in treating pain associated with headache and carpal tunnel syndrome. A study comparing amitriptyline (a tricyclic antidepressant used to treat pain) and vitamin B6 in the treatment of headache demonstrated equal effectiveness, with fewer side effects in those using vitamin B6 (Bernstein AL 1990). It is likely that vitamin B6 works to reduce pain by raising serotonin levels (Bernstein AL 1990). People who have chronic pain or headaches may have a serotonin deficiency (Bernstein AL 1990).

Vitamin B6 has a well-established record in the management of certain chronic pain syndromes. It may offer an alternative to surgery for carpal tunnel syndrome, which may be caused in part by a vitamin B6 deficiency (Aufiero E et al 2004; Ellis J et al 1981). A combination of B vitamins has also been demonstrated to allow a shorter course of treatment for people who have painful degenerative spinal diseases (Vetter G et al 1988). The painful response to thermal injury was inhibited by the combination of niacin, B6, and B12 in laboratory rats (Wang ZB et al 2005).

Many older people may be deficient in vitamin B6 either because of low intake, a higher requirement, or health problems that alter vitamin B6 levels (Mahan LK et al 1996). People who have multiple health problems have a higher risk of vitamin B6 deficiency (Mahan LK et al 1996). Up to 20 percent of women who take birth control pills have a deficiency in vitamin B6 (Mahan LK et al 1996).

Studies examining toxicity in long-term use of vitamin B6 found that adults using 100 to 150 mg daily for 5 to 10 years had minimal or no toxicity (Bernstein AL 1990).

Vitamin B12. A link between vitamin B12 levels and pain has been noted (Bernard MA et al 1998). Older individuals who have vitamin B12 deficiency experience more pain than those who have normal vitamin B12 levels (Bernard MA et al 1998).

In a study examining vitamin B12 and pain, patients with lower back pain received injections of vitamin B12 or placebo into muscle tissue. Patients treated with vitamin B12 reported a significant decrease in pain and disability, and used less acetaminophen, compared to placebo-treated patients. These findings are particularly interesting because there were no signs of nutritional deficiency (Mauro GL et al 2000). Vitamin B12 has also been used successfully to treat the pain of degenerative neuropathy (Sun Y et al 2005).

Many animal studies have demonstrated the reduced pain that occurs in response to combining vitamin B12 or B complex with conventional pharmaceuticals used to treat neuropathic or inflammatory pain (Caram-Salas NL et al 2004; Granados-Soto V et al 2004; Medina-Santillan R et al 2004; Reyes-Garcia G et al 2004; Rocha-Gonzalez HI et al 2004).

Vegetarians who completely avoid animal foods may develop vitamin B12 deficiency, which is linked to neuropathy; older people are also at risk because absorption decreases with age (Mahan LK et al 1996). Poor vitamin B12 status may cause painful neuropathy. On the other hand, in one study, a strict vegan diet rich in lactobacilli produced significant reduction in pain and other symptoms of rheumatoid arthritis, despite lower vitamin B12 levels (Nenonen MT et al 1998).

Vitamin C. Vitamin C, a versatile antioxidant, is another natural shield against pain (McAlindon TE et al 1996). One study found that pain and cartilage loss associated with knee osteoarthritis was reduced in people who had a high vitamin C intake (McAlindon TE et al 1996). Another study looking at the effects of 1000 mg daily of calcium ascorbate (a buffered vitamin C) taken for 14 days by 133 patients who had osteoarthritis found significant decrease in pain on the visual analog scale, as well as improved function of the joints compared to the placebo group (Jensen NH 2003).

Vitamin E. Vitamin E (tocopherol) blocks pain, enhances natural endorphin activity, and acts as an antioxidant (Kryzhanovskii GN et al 1988; Machtey I et al 1978). A study of women who had painful menstruation found that vitamin E reduced discomfort and increased endorphin levels (Kryzhanovskii GN et al 1988).

Vitamin E was tested for effectiveness against pain in a double-blind study involving 50 people who had primary degenerative osteoarthritis. Participants were given either vitamin E or placebo. After 6 weeks, the vitamin E group reported less pain while moving or at rest and less pain when joints were subjected to pressure (Blankenhorn G 1986).

In another test of vitamin E against osteoarthritis, 29 patients were given vitamin E for 10 days. The same 29 patients were then given only a placebo for the next 10 days (Machtey I et al 1978). When the patients were taking vitamin E, 52 percent reported relief from pain. Only 4 percent reported pain relief while taking the placebo (Machtey I et al 1978).

Herbs That May Relieve Pain

Capsaicin. Capsaicin, a chemical found in cayenne and other peppers, is a prime ingredient of over-the-counter and prescription analgesic ointments. Capsaicin works by stimulating the release of substance P from pain-receptor cells called C fibers. Prolonged exposure to capsaicin depletes the C fibers, making them incapable of transmitting painful stimuli. Capsaicin has been shown to reduce the pain of shingles, postherpetic neuralgia, osteoarthritis, and diabetic nerve pain (Deal CL et al 1991; Pfeifer MA et al 1993; Rains C et al 1995; Tandan R et al 1992). Rubbing capsaicin on the skin produces an immediate sensation of heat and a temporarily increased sensitivity to pain (hyperalgesia) as substance P is released (Ashkenazi A et al 2004). Thirty percent of patients discontinue using capsaicin because of these unpleasant, temporary side effects (Ashkenazi A et al 2004). These adverse effects typically disappear after the first week of treatment, so it is well worth sticking with the treatment to achieve the long-term pain relief that capsaicin can provide (Rains C et al 1995).

Curcumin. Curcumin is the active ingredient in turmeric root that adds color and flavor to curry and other foods. It has anti-inflammatory properties and has been used to combat the pain and swelling of arthritis (Lodha R et al 2000). Curcumin can inhibit the release of inflammatory mediators and inhibit the COX enzyme (Huang MT et al 1991; Joe B et al 1997). It may also work as an enkephalinase inhibitor (the enzyme that degrades natural endorphins), serving to increase levels of natural endorphins by slowing their destruction (Kita A et al 1997).

Devil's claw. Several pharmacologic studies using animal models of inflammation have found that devil's claw root produces powerful anti-inflammatory and analgesic effects (Blumenthal M 2000). In one study, 122 patients who had osteoarthritis of the knee and hip were treated with either devil's claw or the drug diacerhein for 4 months (Chantre P et al 2000). Both groups experienced similar pain relief, but the group taking devil's claw experienced significantly decreased side effects, particularly less gastrointestinal distress (Chantre P et al 2000). Other studies in Germany and France have found that the herb's ability to alleviate pain and inflammation compares favorably with that of cortisone and phenylbutazone (Blumenthal M 2000; Brady LR 1981). In another study, people who had lower back pain felt significant relief after taking 2400 mg of devil's claw daily for 4 weeks (Blumenthal M 2000).

Ginger root. Ginger root has exhibited anti-inflammatory and analgesic effects and has also been used to treat headache, nausea, and vomiting. One component in ginger, called (6)-shogaol, has a capsaicin-like chemical structure and works to deplete stores of substance P (Onogi T et al 1992). Similar to NSAIDs, components in ginger can inhibit the COX enzyme, which reduces inflammation (Kiuchi F et al 1992). Clinical trials show that ginger can reduce the pain associated with arthritis (Srivastava KC et al 1992).

Proanthocyanidins. Proanthocyanidins possess extraordinary antioxidant properties that may be of value in reducing pain (Li WG et al 2001). Proanthocyanidins have shown analgesic and anti-inflammatory activity in mice (Subarnas A et al 2000). A small study found that grape seed proanthocyanidin extract reduced the frequency and intensity of abdominal pain associated with chronic pancreatitis (Banerjee B et al 2001). For chronic pain, 100 mg of proanthocyanidins can be taken twice daily for 4 to 6 months; then the dosage can be reduced by half.

Fatty Acid Nutrition and Pain

Essential fatty acids have special value in fighting pain. Gamma-linolenic acid (GLA) is an omega-6 fatty acid derived from evening primrose, borage, and black currant oils (Leventhal LJ et al 1994). Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are omega-3 fatty acids that are derived from flax and perilla and are found in fish oils (Mahan LK et al 1996). These essential fatty acids are important in manufacturing prostaglandins E1 and E3, which help to reduce inflammation and pain, while reducing proinflammatory prostaglandin E2 (Mahan LK et al 1996). In fact, infusions of prostaglandin E1 are commonly used to treat intermittent claudication, a painful, chronic, vascular condition caused by poor blood flow.

The omega-3 fatty acids have been found not only to protect against heart disease but also to reduce the inflammation and pain of rheumatoid arthritis. Studies show that patients with rheumatoid arthritis experience a decrease in joint stiffness and tenderness after 3 months of treatment with omega-3 fatty acids (Fortin PR et al 1995; Kremer JM et al 1985). Other studies have found that patients who consume fish oil were able to significantly reduce their intake of NSAIDs, compared with subjects in a control group (Lau CS et al 1993; Skoldstam L et al 1992).

Part of the effectiveness of omega-3 fatty acids may come from their ability to inhibit proinflammatory cytokines (such as TNF-alpha and IL-6) (James MJ et al 1997). For more information on reducing inflammation, see the chapter Inflammation.