If you do add a zinc supplement, Newmark suggests that children with ADHD take no more than 20 milligrams daily. Oner, Ozgur, et al.

How much zinc should an adult with ADHD take?

Moreover, 150 mg/day zinc supplementation for 12 weeks led to a significant reduction in symptoms of hyperactivity, impulsivity, and impaired socialization in patients with ADHD⁵³.

What kind of zinc should I take for ADHD?

A study of ADHD treatment with zinc sulfate as a supplement to methylphenidate showed beneficial effects of zinc supplementation in the treatment of children with ADHD. The dose of zinc sulfate used was 55 mg/day, which is equivalent to 15 mg zinc.