Discusses tricyclic antidepressants for chronic pain. Includes generic and brand names such as amitriptyline, doxepin (Silenor, Zonalon), and imipramine (Tofranil). Covers why they are used, how well they work, and possible side effects.
Tricyclic Antidepressants for Chronic Pain
How It Works
Antidepressants increase the levels of
certain brain chemicals that improve mood and regulate pain signals. Low doses
of antidepressants also relieve pain, although it is not known exactly
Why It Is Used
These medicines are often used in
lower doses when they are used to treat chronic pain than when they are used to
treat depression. In low doses, these medicines relieve pain. In higher doses,
they have antidepressant effects.
These medicines are reserved for
long-term (chronic) pain syndromes. They may be more effective if you also have
chronic pain caused by nerve problems such as
diabetic neuropathy. They may help relieve sleeping
problems and fatigue caused by chronic pain. Your doctor may prescribe
antidepressants for use at bedtime because they can cause drowsiness.
How Well It Works
These medicines are helpful in the
management of chronic pain, especially nerve pain.1
All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.
Here are some important things to think about:
Usually the benefits of the medicine are more important than any minor side effects.
Side effects may go away after you take the medicine for a while.
If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.
Call 911 or other emergency services right away if you have:
Swelling of your face, lips, tongue, or throat.
Call your doctor right away if you have:
Thoughts of suicide.
Agitation and restlessness.
Nausea and vomiting.
Common side effects of this medicine include:
The U.S. Food and Drug Administration (FDA) has issued an advisory on antidepressant medicines and the risk of suicide. Talk with your doctor about these possible side effects and the warning signs of suicide.
Drug Reference for a full list of side effects. (Drug Reference is not
available in all systems.)
What To Think About
Never suddenly stop taking tricyclic antidepressants (TCAs). The use of any antidepressant should be tapered off slowly and only under the supervision of a doctor. Abruptly stopping antidepressant medicines can cause negative side effects or a relapse of your condition.
TCAs are started at low doses, and the dose is increased gradually to reduce the severity of side effects. You may need regular blood tests to check the amount of the medicine in your blood. Too much of this type of medicine in the bloodstream can be dangerous.
You may start to feel better in 1 to 3 weeks of taking antidepressant medicine. But it can take as many as 6 to 8 weeks to see more improvement. If you have questions or concerns about your medicines or if you do not notice any improvement by 3 weeks, talk to your doctor.
People who have seizures (epilepsy), difficulty urinating (urinary retention), glaucoma (an eye disease), or heart conditions may notice that TCAs make these symptoms worse.
These medicines can also affect blood sugar levels in people who have diabetes. If you notice that the results of your blood sugar tests are different than you expect, or if you have any questions, talk with your doctor.
Be sure to tell your doctor about all the medicines you are currently taking. TCAs can interact poorly with certain heart medicines—for example, digoxin (such as Lanoxin)—and/or with other medicines, including those used to treat seizures. One example is phenytoin (Dilantin).
Dry mouth is common with these medicines. To help with dry mouth, you can chew sugarless gum, suck on sugarless candy, or melt ice in your mouth. If you continue to have problems with dry mouth after a couple of weeks, call your doctor. Dry mouth can lead to tooth decay and gum disease.
These medicines can make your skin more sensitive to the sun.
Stay out of the sun, if possible.
Wear long pants, long-sleeved shirts, and hats, if possible.
Use sunscreen with an SPF that your doctor recommends.
Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.
There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.
Advice for women
If you are pregnant, breast-feeding, or planning to get pregnant, do not use any medicines unless your doctor tells you to. Some medicines can harm your baby. This includes prescription and over-the-counter medicines, vitamins, herbs, and supplements. And make sure that all your doctors know that you are pregnant, breast-feeding, or planning to get pregnant.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.
Drugs for pain (2010). Treatment Guidelines From The Medical Letter, 8(92): 25–34.
How this information was developed to help you make better health decisions.