Tricyclic antidepressants (TCAs) are a class of medications used in the management of mood disorders, primarily depression. These agents, named after their 3-ring chemical structure, act via reuptake inhibition of neurotransmitters (particularly norepinephrine and serotonin) in the brain. In effect, there is an increased concentration of neurotransmitters in the synapse. Histaminic, muscarinic, and adrenergic receptors are also blocked, leading to a wide array of side effects. For decades, TCAs have been utilized for depression and are considered alternative antidepressant options to selective serotonin reuptake inhibitors (SSRIs). Full effects take a latent period of around 2â€“3 weeks. Overdose can lead to cardiac toxicity, seizures, and coma. Other uses include treatment for anxiety disorders, chronic pain syndrome, and nocturnal enuresis.