This article reports that children with autism taking a low dose of vitamin B6 and magnesium had no major side effects of the treatment, but also did not have improved behavior.

Several researchers have shown that children with autism can benefit from taking high doses of vitamin B6, sometimes combined with magnesium. The authors of this article wanted to determine whether the same effect would occur with low doses of vitamin B6 and magnesium. Fifteen children with autism and five controls were compared over time in their behavioral responses to treatment with either vitamin B6 and magnesium, or placebo. Vitamin B6 was given at 200 mg/70 kg body weight per day (about 52 mg for a 40-pound child), and magnesium was given at 100 mg/70 kg body weight per day (about 26 mg for a 40-pound child). Both supplements were taken over a 10-week period, then either continued for another 10 weeks or replaced with placebo. No differences in behavior were found over the treatment periods or between children with autism and controls.