Carpal tunnel syndrome has become a prevalent malady in the workplace. Many doctors advise trying to relieve symptoms with non-surgical options before considering endoscopic or open release surgery, says the National Institutes of Health. One non-surgical option sought by many is vitamin therapy, especially using vitamin B-6. In spite of the many studies examining vitamin B-6 for carpal tunnel syndrome, and the large number of those using this therapy, the evidence for its effectiveness is lacking, according to the NIH.
Carpal Tunnel Syndrome
The Mayo Clinic says carpal tunnel syndrome is an entrapment neuropathy of the median nerve. The median nerve inside the wrist's carpal tunnel becomes compressed or squeezed. This squeezing occurs because the tendons adjacent to the nerve swell and apply pressure to the nerve. This results in neuropathy, which means there is a problem in the nerve's ability to send sensory and motor signals between the spinal cord and periphery. The result is pain, weakness, numbness and other symptoms characteristic of carpal tunnel syndrome. Many therapies focus on reducing the swelling in the tendons so that pressure on the median nerve can be relieved.
Functions of Vitamin B-6
This vitamin has many important roles throughout the body. It is a necessary element for making proteins and is required in over 100 enzymatic reactions for protein metabolism, says NIH. In the nervous system, vitamin B-6 is required to manufacture the neurotransmitters dopamine and serotonin. These chemicals are necessary for nerve cells to communicate. Vitamin B-6 also may have a role in the cause of chronic pain, Parkinson's disease, seizures and headaches, says NIH.
Risks
Taking excessive amounts of vitamin B-6 from supplements can have damaging effects. The primary damaging effect is on peripheral nerves, which can result in neuropathy. The NIH says that such neuropathy can be reversed if the excessive vitamin B-6 intake is discontinued. The NIH also suggests that the upper tolerable limit for vitamin B-6 in adults is 100 mg per day, although other sources suggest vitamin B-6 levels from supplements are safe if limited to 200 mg per day.
The Pros
The NIH says that recommendations for vitamin B-6 to treat the symptoms of carpal tunnel syndrome began about 30 years ago. Today, many popular books still suggest a dose of 100 mg to 200 mg per day of vitamin B-6 to remedy carpal tunnel syndrome. Vitamin B-6 supplements for treating a painful condition like carpal tunnel syndrome are indeed attractive since supplements are easy and inexpensive. However, their effectiveness is controversial. Despite this controversy many physicians still prescribe vitamin B-6 for carpal tunnel syndrome. There is little evidence for a direct role of vitamin B-6 in alleviating carpal tunnel syndrome. Yet vitamin B-6 may help in another way. It is possible that this vitamin can raise pain threshold levels that can make the discomfort of carpal tunnel syndrome less severe.
The Cons
NIH's conclusion is that despite the widespread use of vitamin B-6 as a treatment for carpal tunnel syndrome, the available scientific data do not support it as an effective remedy. The NIH also warns that anyone taking excessive doses of vitamin B-6 as a carpal tunnel remedy risks the harmful neurological effects of too much intake. The NIH asserts that there are documented cases of peripheral neuropathy caused by excessive vitamin B-6 intake for treating carpal tunnel syndrome.
