A method of treating neurotransmitter dysfunction in a patient. The method includes the step of administering an amino acid precursor of a catecholamine in a balanced and effective therapeutic range. The catecholamine precursor is preferably L-dopa, but may alternatively be tyrosine, D,L-Phenylalanine or an active isomer thereof, and N-acetyl-L-tyrosine or other amino acid precursor of L-dopa. An amino acid precursor of serotonin in an effective therapeutic range, is also administered. The serotonin precursor is preferably 5-HTP, but may alternatively be tryptophan. At least one cofactor is also preferably administered. Cofactor options include Vitamin B6, Vitamin C, Calcium, Folate, and Cysteine. A method of periodic administration and patient checking is also disclosed.