Most antidepressants are believed to work by slowing the removal of certain chemicals from the brain. These chemicals are called neurotransmitters (such as serotonin and norepinephrine). Neurotransmitters are needed for normal brain function and are involved in the control of mood and in other responses and functions, such as eating, sleep, pain, and thinking.
Antidepressants help people with depression by making these natural chemicals more available to the brain. By restoring the brain's chemical balance, antidepressants help relieve the symptoms of depression.
Specifically, antidepressant drugs help reduce the extreme sadness, hopelessness, and lack of interest in life that are typical in people with depression. These drugs also may be used to treat other conditions, such as obsessive compulsive disorder, premenstrual syndrome, chronic pain, and eating disorders.
Typically, antidepressants are taken for 4 to 6 months. In some cases, however, patients and their doctors may decide that antidepressants are needed for a longer time.
