Hi, Focalin is composed of Dexmethylphenidate , which is a mild stimulant to the central nervous system. It affects chemicals in the brain that contribute to hyperactivity and impulse control. Hence, it is used to treat attention deficit hyperactivity disorder (ADHD). More common side effects which are encountered include acidity in stomach, belching, heartburn, indigestion, loss of appetite, nausea, stomach discomfort, throat pain and weight loss. It is not dangerous to take the medication, but it would be better to do it under medical supervision. Other co-morbid conditions like cancer, high blood pressure, diabetes and heart problems does not seem to be related directly to the intake of this medication. Dexmethylphenidate may be habit-forming, and this medicine is a drug of abuse. However, it can cause stroke, heart attack, and sudden death in people with high blood pressure, heart disease, or a heart defect. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Ashakiran S, General & Family Physician