Will vitamin B6 supplements relieve my asthma?

Pyridoxal 5'-phosphate (PLP), the active form of vitamin B6 in the body, is involved in many biochemical processes, and has been found in lower concentrations in asthma patients. However, studies of the therapeutic efficacy of B6 supplementation have produced mixed results. One showed that treating asthmatic adults with pyridoxine (50 mg twice daily) reduced asthma exacerbation and wheezing episodes. A study of children showed that B6 supplementation (100 mg pyridoxine hydrochloride twice daily) resulted in fewer bronchoconstrictive attacks; less wheezing, coughing, and chest tightness; and lower usage of bronchodilators and steroid medications. However, a double-blind trial of B6 (300 mg per day pyridoxine hydrochloride) in steroid-dependent asthma patients showed no change in lung function.

Asthma patients treated with the bronchodilator theophylline have lower blood levels of PLP, though it is not used as often as it once was. Patients using this drug should be monitored for vitamin B6 levels and supplements should be given if warranted.