Attention-deficit hyperactivity disorder (ADHD) as a pyridoxine-dependent condition: Urinary diagnostic biomarkers

Almost identical parameters of TRP degradation in untreated ADHD and epileptic patients allow to assume that inborn disorders of vitamin B6 metabolism are the common biochemical background of both diseases. The disturbed activity of PLP dependent enzymes apparently forms those profound disturbances of neurotransmitter systems, which are inherent in ADHD: low concentrations of monoamines and disordered amino acid metabolism. If vitamin B6 disorders are the core biochemical disturbances inherent in ADHD, then the long-term pyridoxine treatment is pathogenetically based replacement therapy of the disease. According to our data, multi-year pyridoxine treatment normalizes completely the pattern of ADHD behavior, without causing any serious side effects.