Amitriptyline is an antidepressant drug that doctors prescribe to treat depression. It also has off-label uses for other mental and physical health conditions.

Amitriptyline is a drug in the tricyclic antidepressant (TCA) family.

TCAs were introduced in the late 1950s as a treatment for depression. Since then, other less toxic drugs have become available. Among them are selective serotonin reuptake inhibitors, better known as SSRIs.

Doctors prescribe amitriptyline to people with depression who have not responded to other antidepressants. There are additional uses for amitriptyline that the Food and Drug Administration (FDA) have not approved.

Read on to learn more about the uses, side effects, warnings, and potential interactions of amitriptyline.

amitriptylineShare on Pinterest
Amitriptyline is a prescription antidepressant drug.

Amitriptyline is a TCA. Antidepressants in this family increase the amount of serotonin and norepinephrine in the brain. These two chemical messengers - neurotransmitters - are involved in depression.

The structure of amitriptyline allows it to attach to receptors in the brain called alpha-adrenergic, histaminic, and muscarinic receptors. This means that amitriptyline can cause more side effects than some other TCAs.

Some examples of other drugs in the TCA class include:

  • clomipramine
  • desipramine
  • doxepin
  • imipramine
  • nortriptyline
  • protriptyline
  • trimipramine

There are six dosages of amitriptyline: 10 milligrams (mg), 25 mg, 50 mg, 75 mg, 100 mg, and 150 mg.

Amitriptyline was once manufactured under the brand Elavil, but only generic forms of the drug are currently available.

Doctors prescribe amitriptyline to treat depression in adults.

They may also use the drug in ways that the FDA has not approved, known as off-label uses. For example, a doctor may recommend amitriptyline as an off-label treatment for:

Share on Pinterest
Taking amitriptyline can cause dizziness and drowsiness.

The most common side effects of amitriptyline are:

Amitriptyline may also cause blurred vision, urinary retention, a rapid heartbeat, and acute-angle glaucoma when it binds to muscarinic receptors in the body.

When amitriptyline attaches to histaminic receptors, it may cause sedation, confusion, and delirium.

People who have seizures should use amitriptyline with caution because it can lower the seizure threshold.

Serious cardiac side effects can occur when amitriptyline binds to alpha-adrenergic receptors in the heart. Low blood pressure upon standing and heart rate fluctuations and irregularities are some of these effects.

When treating depression with amitriptyline, doctors usually prescribe a starting dosage of 25 mg per day — at bedtime because it can cause drowsiness. For off-label uses, doctors may prescribe dosages of 10–20 mg per day.

Depending on a person's response to the medication, the doctor may increase the dosage by 25 mg every 3–7 days. The effective dosage of amitriptyline is one that controls symptoms without causing too many side effects.

The maximum daily dosage of amitriptyline is 150–300 mg per day.

When the dosage is correct, people should notice their symptoms improving within 2–4 weeks. The doctor will recommend maintaining an effective dosage for at least 3 months to prevent symptoms from returning.

If a person wants to stop taking amitriptyline, it is important to develop a tapering schedule with a doctor to prevent withdrawal symptoms. Stopping amitriptyline abruptly can cause side effects.

It is important to gradually reduce the dosage of amitriptyline to prevent withdrawal symptoms.

Withdrawal symptoms can include:

  • nausea
  • headache
  • general discomfort

A doctor will recommend a tapering schedule. An individual approach is key because each person may have a different reaction to stopping the drug.

Keeping track of any symptoms and informing the doctor can help them judge whether to speed up or slow down the tapering.

Short-term studies have shown that antidepressants can increase the risk of suicidal thoughts and behaviors in children, adolescents, and young adults. Research has not shown that people older than 24 years experience these or similar effects.

Before prescribing amitriptyline to a child, adolescent, or young adult, the doctor should weigh the benefits and risks carefully. During treatment, doctors and caregivers need to monitor people taking amitriptyline for worsening symptoms of depression, suicidal thoughts, and unusual behaviors.

Anyone who has experienced an allergic reaction to amitriptyline should refrain from using this drug.

If a person has a history of cardiac problems, such as arrhythmia, heart failure, or a recent heart attack, a doctor should not prescribe amitriptyline.

Anyone over 50 and anyone with a history of heart trouble will undergo an electrocardiogram before beginning amitriptyline treatment. They will repeat this test during treatment so a doctor can check for new or worsening heart conditions.

Amitriptyline can worsen existing angle-closure glaucoma, urinary retention, and seizures. It is important to discuss any symptoms with a doctor, who can rule out these issues, before beginning treatment.

Doctors should prescribe lower doses of amitriptyline to people with liver or kidney failure.

Suicide prevention

  • If you know someone at immediate risk of self-harm, suicide, or hurting another person:
  • Call 911 or the local emergency number.
  • Stay with the person until professional help arrives.
  • Remove any weapons, medications, or other potentially harmful objects.
  • Listen to the person without judgment.
  • If you or someone you know is having thoughts of suicide, a prevention hotline can help. The National Suicide Prevention Lifeline is available 24 hours a day at 1-800-273-8255.

When a person takes amitriptyline and certain other drugs, three critical interactions can occur: monoamine oxidase inhibitor (MAOI) interactions, QT prolongation interactions, and serotonin syndrome interactions.

MAOI interactions

Share on Pinterest
A person may experience an increased body temperature when taking amitriptyline.

MAOIs are another class of antidepressant. A person should not take amitriptyline and an MAOI at the same time. A period of 2 weeks should pass between taking an MAOI and starting amitriptyline.

MAOIs work by blocking the effect of the enzyme monoamine oxidase. This enzyme is responsible for breaking down monoamines in the body.

Monoamines include epinephrine, norepinephrine, dopamine, serotonin, and tyramine. When levels of these chemicals rise in the body, a person may experience:

MAOI drugs include :

  • isocarboxazid
  • phenelzine
  • tranylcypromine
  • selegiline

QT prolongation

The QT interval on an electrocardiogram is an important measure of the electrical conduction of the heart. When this interval lengthens, a person may experience an abnormal heart rhythm, which can lead to arrhythmia.

Amitriptyline can prolong the QT interval. Combining this drug with others that have the same effect puts a person at risk of developing arrhythmia.

Some examples of other drugs that can prolong the QT interval include:

  • astemizole
  • cisapride
  • disopyramide
  • ibutilide
  • indapamide
  • pentamidine
  • pizomide
  • procainamide
  • quinidine
  • sotalol
  • terfenadine

Serotonin syndrome

Serotonin syndrome occurs when there is too much serotonin in the body. This can cause symptoms that can range in severity from mild-to-life-threatening.

Serotonin syndrome symptoms include:

  • dilated pupils
  • flushed skin
  • dry mucous membranes
  • increased bowel sounds
  • excessive sweating
  • increased body temperature
  • a rapid heartbeat
  • muscle rigidity
  • muscle twitching
  • abnormal reflexes agitation
  • anxiety
  • restlessness
  • nausea
  • vomiting
  • tremor
  • disorientation
  • an altered mental status

Amitriptyline increases the amount of serotonin in the brain. When a person also takes other drugs that have this effect, it puts them at risk of developing serotonin syndrome.

Some other drugs that can increase the amount of serotonin in the brain include:

  • isocarboxazid
  • phenelzine
  • procarbazine
  • safinamide
  • selegiline
  • tranylcypromine

The manufacturer has discontinued the Elavil brand of amitriptyline, so only generic forms are available.

The following list shows the prices for 30 tablets of amitriptyline by dosage.

  • Amitriptyline 10 mg: $4.00
  • Amitriptyline 25 mg: $4.00
  • Amitriptyline 50 mg: $4.00
  • Amitriptyline 75 mg: $4.00
  • Amitriptyline 100 mg: $16.82
  • Amitriptyline 150 mg: $23.50

Doctors usually prescribe amitriptyline to treat depression. In addition, some off-label uses include treating anxiety, IBS, and chronic pain.

People taking amitriptyline may experience drowsiness, headaches, and dizziness, among other side effects, some of which are more severe.

Anyone taking any antidepressant should remain watchful for worsening of symptoms. Some people have experienced suicidal thoughts and behaviors while taking amitriptyline, and this requires immediate medical attention.

Also, some drugs can interact with amitriptyline. It is crucial that doctors and pharmacists carefully weigh the benefits and risks of adding amitriptyline to a person's care plan.