A recent study clinically and biologically analyzed 40 children with clinical symptoms of ADHD during a magnesium-vitamin B6 regimen (6 mg/kg/d Mg, 0.6 mg/kg/d vit-B6) for at least 8 weeks. Symptoms of ADHD (hyperactivity, aggressiveness, lack of attention at school) were scored; in parallel, intraerythrocyte Mg2+ was measured. Children from the ADHD group showed significantly lower intraerythrocyte Mg2+ values than control children. In almost all cases of ADHD, the Mg-B6 regimen for at least two months significantly modified the clinical symptoms of the condition: namely, hyperactivity and aggressiveness were reduced and school attention was improved. In parallel, the Mg-B6 regimen led to a significant increase in Erc-Mg values.