Amitriptyline is included in a group of medications classified as tricyclic antidepressants. Amitriptyline is one of the first successful medications in this class to be developed. It was discovered in the late 1930s before scientists had today’s understanding of the chemistry of the brain. This drug was developed as a way to reduce anxiety. Frequently, people with depression are often very anxious. When amitriptyline was given to patients with anxiety, it also improved the depression. This result prompted further research and the development of newer agents to treat depression. As scientific understanding of the brain progressed, scientists discovered that amitriptyline and related compounds worked on a series of chemicals called neurotransmitters. The antidepressants influenced the production and efficiency of these neurotransmitters.
Subsequent work revealed that one of the neurotransmitters, serotonin, is involved in mood and emotion, pain regulation, and the regulation of the blood vessels in migraine. Another neurotransmitter, norepinephrine, is also involved in pain processing in the brain.
Amitriptyline influences the body's use of serotonin and norephinephrine thus leading to improvement in depression and several types of chronic pain. It is used to treat chronic tension-type headache as well as migraine headache. Its effectiveness in treating any of these conditions, especially headache, is not related to whether or not the individual has depression.
Although side effects, such as dry mouth, increased appetite and constipation may occur, consultation with the physician may help minimize the likelihood and severity of these effects. It can cause sedation and can be taken at night to help sleep.