A few studies have investigated the effectiveness of vitamin B6 specifically for carpal tunnel syndrome. Most were poorly designed and involved few people. The two (albeit small) randomized, double-blind, placebo-controlled studies that do exist found no evidence that vitamin B 6 effectively treats carpal tunnel.
The first study, which enrolled only 15 people, found no significant difference after 10 weeks among those taking vitamin B6, placebo, or nothing at all.4
The second, involving 32 people, did find some benefits, but these were fairly minor.5 There was no improvement in nighttime pain, numbness, or tingling, nor in objective measurements of median nerve function. Some benefit, however, was seen in the relatively less important symptoms of finger swelling and discomfort after repetitive motion.
Again, the thought that vitamin B6 might be helpful to take for carpal tunnel syndrome is based on the fact that some people with with this health challenge were found to be deficient in the vitamin. However, this does not mean that supplementing the vitamin will actually help treat the condition.
More than 25 years ago, researchers noted that people with carpal tunnel syndrome seemed to be deficient in vitamin B6.2 This led to widespread use of B6 as a treatment for carpal tunnel. However, a recent study found no association between CTS and B6 -deficiency.3 In any case, even if B6 -deficiency were common in CTS, that by itself wouldn't prove that taking B6 supplements can reduce carpal tunnel syndrome symptoms.
Since vitamin B6 has not been proven effective and may be harmful in high doses, it should be taken with caution for carpal tunnel syndrome.
