Known brand names include Elavil.
A tricyclic antidepressant taken by mouth as tablets to relieve symptoms of depression. It is sedating and has strong atropine-like effects such as dry mouth and constipation, and an overdose can cause deadly heart rhythm problems and seizures. Like other antidepressants, it carries a boxed warning about suicidal thoughts in children, teens, and young adults.
Exactly how amitriptyline works in people is not known. It blocks the pumps that nerve cells use to take back two chemical messengers, norepinephrine and serotonin, after releasing them. That leaves more of these messengers active between nerve cells for longer, which some experts believe is what relieves depression. It is not an MAO inhibitor and does not work mainly by stimulating the brain.
The liver breaks it down, and people with a less active form of the liver enzyme CYP2D6, or who take drugs that block that enzyme, can build up much higher levels. A calming, sleepy effect may show up before the mood benefit, which can take as long as 30 days. Its atropine-like action causes dry mouth, constipation, blurred vision, and trouble passing urine, and by widening the pupils it can set off a sudden glaucoma attack in people with narrow eye angles. It can also slow electrical signals in the heart and cause abnormal rhythms, especially at high doses, which is a main reason an overdose is so dangerous.
Amitriptyline is a tricyclic antidepressant used to relieve the symptoms of depression. The label notes that depression that seems to arise from within, called endogenous depression, is more likely to improve on it than other kinds. Its goal is to lift low mood and ease the symptoms that come with it, and the full benefit may take a few weeks or longer to appear.
It is taken by mouth as a tablet, often with more of the daily amount at bedtime because it causes drowsiness, and people keep taking it after they feel better to help prevent a relapse. It is not approved for use in children, and teens and older adults generally take lower doses. It is not approved for the depressed phase of bipolar disorder, and it is not used together with MAO inhibitor antidepressants or during early recovery from a heart attack.
Drowsiness, dry mouth, constipation, blurred vision, dizziness on standing, and changes in weight are among the effects people notice. The boxed warning covers a higher risk of suicidal thoughts and behavior in children, teens, and young adults, especially early in treatment or after a dose change. The label also treats abnormal heart rhythms, heart attack and stroke, seizures, serotonin syndrome when it is combined with similar drugs, low blood sodium, angle-closure glaucoma, and a stalled bowel as serious, and an overdose can be fatal.
This is the boxed warning, the warning the FDA label prints first.
In short-term trials in major depressive disorder and other psychiatric disorders, antidepressants raised the risk of suicidal thinking and behavior in children, adolescents, and young adults. No increase was seen in adults over 24, and risk fell in adults 65 and older. Monitor all patients closely for clinical worsening, suicidality, or unusual behavior changes, and enlist families and caregivers. Not approved for pediatric patients.
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