Why is this medication prescribed? Amitriptyline is used to treat symptoms of depression. Amitriptyline is in a class of medications called tricyclic antidepressants. It works by increasing the amounts of certain natural substances in the brain that are needed to maintain mental balance. Amitriptyline is a tricyclic antidepressant used to treat depression and used off-label for insomnia, migraine prevention, ADHD, eating disorders, bipolar disorder, anxiety, psychotic disorders, and nerve pain. Amitriptyline reference guide for safe and effective use from the American Society of Health-System Pharmacists (AHFS DI). What is this medication? AMITRIPTYLINE (a mee TRIP ti leen) treats depression. It increases the amount of serotonin and norepinephrine in the brain, substances that help regulate mood. It belongs to a group of medications called tricyclic antidepressants (TCAs). Find patient medical information for Amitriptyline (Amitid, Elavil, Endep) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Amitriptyline may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you or your caregiver notice any of these adverse effects, tell your doctor right away. Amitriptyline is indicated for the treatment of major depressive disorder, neuropathic pain, and for the prevention of migraine and chronic tension headache. It can be used for the treatment of nocturnal enuresis in children older than 6 after other treatments have failed. [11].