Carpal tunnel syndrome, injury to the nerve that runs through the wrist, causes disabling pain and loss of strength in the fingers and hand. Conservative treatment of carpal tunnel syndrome consists of splinting and immobilizing the wrist, anti-inflammatory or steroid medications to reduce inflammation and swelling that compresses the nerve and massage or stretching exercises. If conservative measures fail, surgery provides relief in 95 percent of cases. Vitamin B therapy has shown no benefit in most clinical trials, but may benefit specific cases. Do not take vitamin B supplements without your physician’s approval.
The vitamin B-complex includes a number of vitamins, including B1, also known as thiamine; B2, known as riboflavin, B3, known as niacin; B5, known as pantothenic acid; B6, known as pyrodoxine; B7, known as biotin; B9, known as folate or folic acid and B12, known as cobalamin. B2, B12 and particularly B6 have been used to treat carpal tunnel syndrome.
The B-complex vitamins play a part in maintaining the nervous system, among other functions. Vitamin B deficiencies can cause numbness and tingling in the extremities and muscle cramping.
B6 has been prescribed as an adjunct to conservative treatment for carpal tunnel syndrome for 30 years, but studies have failed to show any benefit with doses of 100 to 200 mg daily, the National Institutes of Health reports. B6 does act as an analgesic by raising the pain threshold and may help relieve pain. People who develop carpal tunnel symptoms as a result of vitamin B6 deficiency may also benefit from B6 therapy, lead author and registered dietitian Milly Ryan-Harshman, PhD, reported in the July 2007 “Canadian Family Physician.”
A study reported in the April 2005 “Journal of the Neurological Sciences” by lead author Yoshihiro Sato, M.D. of Mitate Hospital in Japan found that mecobalamin, an analogue of vitamin B12, significantly improved abnormal nerve function in stroke patients who were overusing their undamaged hand. Riboflavin, B2, has traditionally been used as well to treat carpal tunnel syndrome, although there’s no definitive proof of its effectiveness, MayoClinic.com states. Always discuss vitamin B supplementation with your physician before starting therapy.
Taking more than 200 mg of B6 daily can cause nerve damage, or neuropathy to your arms and legs, which is reversible when you stop the supplement, according to the NIH. The Institute of Medicine has established the safe upper limit of vitamin B6 as 100 mg per day for adults based on this information. Do not take more than 100 mg of B6 without your doctor’s permission.
Because B2 or B6 deficiency may cause carpal tunnel symptoms in some cases, taking a daily B-complex vitamin supplement may benefit some people with symptoms.
- Linus Pauling Institute at Oregon State University: Vitamin B6
- National Institutes of Health: Vitamin B6
- Canadian Family Physician: Carpal Tunnel Syndrome and Vitamin B6
- MayoClinic.com: Carpal Tunnel Syndrome
- PubMed: Amelioration by Mecobalamin of Subclinical Carpal Tunnel Syndrome; Yoshihiro Sato, M.D.; April 2005
- University of Maryland Medical Center: Carpal Tunnel Syndrome