synthetic drug used in the treatment of depression and enuresis (bed-wetting). Introduced into medicine in the 1960s, imipramine was the first tricyclic antidepressant, a class named for its three-ring molecular structure. Imipramine inhibits reuptake of the neurotransmitters norepinephrine (epinephrine and norepinephrine) and serotonin in the brain. It is usually administered orally but may be given by intramuscular injection. The drug has a wide variety of side effects, which include dryness of the mouth, blurred vision, constipation, difficulty in passing urine, and cardiovascular abnormalities.