Desipramine is a tricyclic antidepressant (TCA). It inhibits the reuptake of norepinephrine and to a minor extent serotonin. It is used to treat depression, but not considered a first line treatment since the introduction of SSRI antidepressants. Desipramine is an active metabolite of imipramine. desipramine has found use in treating neuropathic pain. The mechanism of action seems to involve the activation, through norepinephrine reuptake inhibition, of descending pathways in the spinal cord that block pain signals from ascending to the brain. Desipramine is one of the most potent and selective medications in this respect. It may also be used to treat symptoms of Attention Deficit Hyperactivity Disorder, as the underproduction of norepinephrine has been increasingly linked to symptoms associated with Attention Deficit Disorder. It may also be used to treat symptoms of cocaine withdrawal.