Amir Raz, a professor of clinical neuroscience in the psychiatry department at McGill, is one of a handful of researchers raising concerns over the continued use of antidepressants in children and teens. "The human brain is developing exponentially when we are very young," he says. "And exposure to antidepressants may affect or influence the wiring of the brain, especially when it comes to certain elements that have to do with stress, emotion and the regulation of these."