Drug therapy is commonly used to control various comorbid health conditions in patients with DS, e.g., methylphenidate is commonly used in DS with attention deficit hyperactivity disorder (ADHD), Cerebrolysin® is used to improve cognitive development, and thyroid hormone and folic acid are used to improve psychomotor development [11], which leads to a high drug use rate in these patients. This evidence concerns the gene TG and attention deficit-hyperactivity disorder.