Depression may affect up to 5% of the general population each year. This program takes a systemic look at this common illness. Neurotransmitters and receptors in the brain are examined, including theories related to how medication provides relief from depression. The three broad categories of antidepressant agents are examined: tricylic agents, selective serotonin reuptake inhibitors, and monoamine oxidase inhibitors. Specific agents within each group are discussed with a focus on drug interactions and precautions, and potential side effects. This video is one of a four-part series.