Carpal Tunnel Syndrome

Opening Up to Relief

They were awkward, all right. But Richard Comstock wasn't about to part with his doctor-prescribed wrist splints, weapons in the fight against his painful, hand-numbing case of carpal tunnel syndrome (CTS).

He wasn't about to abandon hope for a vitamin cure, either. So when the Scotia, New York, resident read that vitamin B₆ might be the light at the end of his CTS pain, he combined treatments.

That was more than a decade ago. He's still taking his trusty vitamin B₆, but Comstock's severe carpal tunnel pain is long gone. And so are the wrist splints. "Every once in a while, I'll have a little problem, but it doesn't keep me awake at night like it used to," says the retired utility supervisor.

Comstock may have been way ahead of his time. Even though over 100,000 carpal tunnel surgeries are performed each year, doctors who prefer a less drastic solution are slowly beginning to add vitamin B₆ to their treatment regimens. "For those people who don't seem to have serious problems, I normally recommend they wear splints at night, take an anti-inflammatory and use B₆ for at least two weeks," says Gary Tunell, M.D., chief of neurology at Baylor University Medical Center in Dallas. Dr. Tunell estimates that 40 to 50 percent of people with CTS could experience some improvement using this therapy.

Some doctors are even more enthusiastic about the use of vitamin B₆ for CTS. "Somewhere around 90 percent of carpal tunnel cases can be cured by B₆," says John Marion Ellis, M.D., a retired Mount Pleasant, Texas, family practitioner who has conducted studies and written papers about B₆ and who has been researching the link between B₆ deficiency and CTS for more than 30 years.

Touring the Tunnel

Just inside your wrist is a narrow, bony passage called the carpal tunnel. Anything but empty, this tunnel contains nine tendons as well as a nerve called the median nerve, all of which are encased, sausage-like, in a slippery sheath called the synovium. When the synovium and tendons become inflamed and swollen, they squeeze the median nerve, which runs to the fingers.

Ever watch a live electrical wire rub metal? The pinched median nerve can send angry sparks of pain, numbness and tingling from your fingertips to your shoulder. More often the pain is in the thumb and the index and middle fingers. Sometimes the ring finger is also involved. Many people who suffer from CTS say it feels like their hands have fallen asleep; others complain of weak grips and stiff fingers.

Women seem to suffer from CTS more often than men. Changes in female hormones caused by pregnancy, taking birth control pills and menopause somehow make the synovium swell. And because women generally have small wrists, just a little swelling is enough to cause carpal tunnel pain, experts say.

Surgeons agree that CTS should not be treated with surgery during pregnancy. Studies by Dr. Ellis found that vitamin B₆ helped relieve CTS in 11 percent of the pregnant women with severe CTS signs and symptoms during their pregnancies. These women were treated with 50 to 300 milligrams of B₆ daily for at least 60 to 90 days before giving birth. And there was no harm to either the mother or the child. If you'd like to try this therapy, you should discuss it with your doctor.

Obesity creates a similar situation. "There is about a fivefold increase in CTS in people who are obese and couch potatoes. So we encourage them to be in better shape and lose weight," says Morton Kasdan, M.D., clinical professor of plastic surgery at the University of Louisville in Kentucky and clinical professor of preventive medicine and environmental health at the University of Kentucky in Lexington.

CTS has also become the unofficial health complaint of the modern age, the result of an increase in cases among people in manufacturing jobs.

Officials at the U.S. Bureau of Labor Statistics don't keep records of the number of CTS cases reported each year. Between 1986 and 1992, cases of "repetitive trauma disorders" (a category that includes CTS and similar conditions) zoomed from 50,000 to 282,000.

Another common culprit is working on a computer, which doesn't require you to take frequent breaks, as changing paper in a typewriter would. "The repetitive activity produces inflammation, and this leads to swelling," explains Dr. Tunell. "That's a major contributor for the patients I see."

The Benefits of B₆

Doctors are divided on why vitamin B₆ seems to provide relief from CTS.

The author of five published studies that demonstrate the benefits of vitamin B₆ for CTS, Dr. Ellis contends that synovium swelling and inelasticity are caused by a B₆ deficiency.

Dr. Ellis and Karl Folkers, D.Sc., Ph.D., professor and director of the Institute for Biomedical Research at the University of Texas at Austin, once healed 22 of 23 people with CTS just by giving them 50 to 300 milligrams of vitamin B₆ daily for at least 12 weeks. And a number of them had already undergone surgery without experiencing relief. "Vitamin B₆ is as important to your body as oxygen and water, only it takes a little longer to show the benefits," says Dr. Ellis.

The average diet, Dr. Ellis says, provides only about 1.4 milligrams of vitamin B₆ a day, in part because the nutrient is lost in processing, so many people are just not getting enough. "Raw foods are the best sources, because heat destroys it," he says. Foods containing B₆ include potatoes, bananas, chicken breast, top round of beef, fish, brown rice and avocados.

Other doctors believe vitamin B₆ acts as a diuretic, helping the body to eliminate excess fluid. "During pregnancy, your feet swell, your hands swell, rings don't fit anymore. You're retaining fluid, especially in the wrists," says Dr. Tunell. For some women, the problem worsens when they lie down, as fluid that makes the ankles swell during the day is redistributed throughout the body, including to the wrists, he says. "B₆ helps you get rid of the extra water gain that's causing carpal tunnel," he says.

Another theory, backed up by two European studies, suggests that vitamin B₆ somehow short-circuits an angry nerve's ability to transmit pain signals. "We don't know the mechanism, but we do know B₆ reduces the amount of pain that animals feel, and that may be what's happening here," says Allan L. Bernstein, M.D., chief of neurology at Kaiser Permanente Medical Center in Hayward, California.

Medical experts do agree on one thing: No matter how vitamin B₆ gets the job done, you have to be careful not to take too much. In studies using laboratory animals, researchers found that excess B₆ can harm your central nervous system.

Researchers at the U.S. Department of Agriculture Western Human Nutrition Research Center in San Francisco fed 12 experimental animals 1, 10, 100, 200 or 300 times their requirement of vitamin B₆ for seven weeks. At the three highest levels of B₆ intake, the animals' reaction time to a loud noise was reduced. Signs of a B₆ overdose also include an oversensitivity to sunlight, which produces a skin rash and numbness.

"Vitamin B₆ toxicity symptoms are rarely seen in healthy individuals. Moderate supplementation of B₆ will not cause that kind of thing," says Robert A. Jacob, Ph.D., research chemist in micronutrients at the Western Human Nutrition Research Center. "You'd have to megadose on it. So I don't think that would happen if you take just a multivitamin/mineral supplement with B₆ or even a 50- or 100-milligram B₆ supplement. It appears only when you chronically take massive amounts."

Doctors recommend 50 to 200 milligrams of vitamin B₆ daily to treat carpal tunnel.

Some Recommend Riboflavin and Biotin

There's some evidence that vitamin B₆ won't work properly unless you're getting adequate amounts of riboflavin and biotin, other B vitamins. "Each one of these vitamins is synergistic; each works in concert with the other," says Flora Pettit, Ph.D., a research scientist at the Biochemical Institute at the University of Texas at Austin. Doctors suggest aiming for 300 micrograms of biotin and 25 milligrams of riboflavin daily.

By law, most cereals, flours and other grain products are fortified with riboflavin; milk, yogurt and cheeses are good sources, too. Biotin is found in brewer's yeast, soy flour, cereals, egg yolks, milk, nuts and vegetables.

Older adults, alcoholics and those with nutritionally poor diets are at particular risk for deficiencies in these vitamins, says Dr. Tunell. "Generally, the elderly have poor diets, and they have trouble absorbing B vitamins anyway," says Dr. Tunell. "So they couldn't go wrong with a B-complex supplement unless they have Parkinson's disease. In that case, vitamin B₆ may interfere with the absorption of their levodopa medication."

"My patients are getting between 50 and 100 milligrams of vitamin B₆ and riboflavin a day, using a B-complex supplement," says Dr. Kasdan. "And 60 percent of them have gotten better."

Most doctors agree that catching CTS early is a key to successful treatment. "If you have severe carpal tunnel, the vitamin B₆ isn't really going to reverse it," says Dr. Bernstein. "But if you catch it early, when you're just starting to have pain and tingling, and if there's no weakness and it bothers you at night but not during the day, you'll do extremely well."