Anthony Kroll was 17 years old. Too young to have been a Cerebral patient, according to company policy. Too young to get mental-health treatment without his parents’ consent in his home state of Missouri. So how did a minor end up getting a prescription for an antidepressant that required an explicit warning for young adults? What was Cerebral treating him for? And why weren’t Anthony’s parents informed? In Part 3 of Uncontrolled Substances, WSJ reporter Khadeeja Safdar investigates what happened to Anthony Kroll.