Disclosed is a single unit oral dosage form having, in combination, inositol and an extended release clonidine or extended release guanfacine. In one aspect, a method for treating ADHD and/or associated symptoms thereof includes administering to an ADHD patient the single unit oral dosage form. In another aspect, a method for treating ADHD and/or associated symptoms thereof includes administering to an ADHD patient inositol in combination with extended release clonidine or extended release guanfacine, whether administered separately or as a single dosage form.