Brief communication: effect of pharmacologic doses of vitamin B6 on carpal tunnel syndrome, electroencephalographic results, and pain.

The role of vitamin B6 as a therapeutic agent in the treatment of carpal tunnel syndrome was examined by monitoring both the standard clinical and electrophysiological parameters for entrapment neuropathy at the wrist. Electroencephalogram (EEG) studies were done in an attempt to identify patients most likely to benefit from B6 treatment. EEGs did not prove useful as predictors of clinical response to vitamin B6. Our patients, however, did not show any abnormalities prior to treatment, and no changes occurred during the treatment period. Motor latency, while the most common screening test for carpal tunnel syndrome, was not significantly changed during the course of treatment. It did not prove to be a useful test for monitoring clinical effectiveness of the treatment. Parameters showing the greatest changes were pain scores and sensory latency, which most closely paralleled clinical assessments. Pain scores, more than any other parameters, were improved in these patients following vitamin B6 treatment. Vitamin B6 has been shown to change pain thresholds in clinical and laboratory studies. This may be the basis of the significant improvement in pain scores when electrophysiologic data showed only mild improvement. This study suggests that vitamin B6 deficiency may not be a cause of carpal tunnel syndrome in spite of the observed therapeutic effect, without toxicity, of vitamin B6 treatment.