Antidepressants.

Antidepressants A growing amount of scientists support the view that people with depression have an imbalance of the brain's neurotransmitters, the chemicals that allow nerve cells in the brain to communicate with each other. They believe that an imbalance in serotonin, one of these neurotransmitters, may be an important factor in the development and severity of depression. Abnormal serotonin functioning is theorized to cause psychological disorders such as depression, anxiety, irritability, abnormal appetite, and sleep …

…effects include: heartburn, drowsiness and difficulty achieving an orgasm. There is much more research needed to answer how these anti-depressants effect the brain. It was only in the early 1990's when Prozac hit the pharmacies. It is hard to conduct a lifetime longitudinal study on a drug that's been around for only over a decade. And each time there is another medication introduced the clock rewinds to zero for that particular pill (Time Magazine Nov.2003).