Suspect ADHD in children, which department should I see? What tests should be done?

Patient's question:

Irritable, always biting his nails, often attacks others
Some doctors say he has malnutrition and calcium deficiency

Doctor's answer:

Hello; Based on your description, this condition of the baby cannot be ruled out as caused by ADHD, but it also cannot be ruled out as caused by hyperthyroidism.
It is recommended to have the baby checked by the neurology department of the hospital and undergo thyroid function tests to rule out hyperthyroidism. Also, pay attention to calcium supplementation. Welcome your consultation and wish the baby a speedy recovery.