Actually every thing in the universe derives from chemical reactions. Indeed the human body functions by chemical reactions. Every thing we see, hear, touch, smell, feel, do are caused by chemical reactions. Alter this formula by any means, drugs, shock, trauma, blow to the head, what you intake, and strange things happen. So it's logical to counter any imbalance by more chemicals or in our case meds. Kind of begs the question then if every thing we see, hear, touch and feel is caused by mere chemical reactions. What is real?