How Tricyclic Antidepressants Can Help Relieve Chronic Pain

Examples

Generic Name	Brand Name
amitriptyline	Amitril, Elavil, Endep
desipramine	Norpramin
doxepin	Adapin, Sinequan
imipramine	Tofranil
nortriptyline	Aventyl, Pamelor

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 how.

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 depression or chronic pain caused by nerve problems such as shingles or 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.

Side effects
Side effects vary among the different medicines in this class. If you have severe or intolerable side effects with one medicine, another medicine may be tried.

Most side effects decrease as therapy continues. Common side effects include:

• Constipation
• Dry mouth
• Blurred vision
• Drowsiness and/or fatigue
• Sedation or confusion
• Lowered blood pressure
• Weight gain
• Tremors and/or sweating
• Inability to urinate
• Increased appetite
• Decrease in sexual function or ability
• Worsening of glaucoma

FDA advisory. The U.S. Food and Drug Administration (FDA) has issued an advisory on antidepressant medicines and the risk of suicide. The FDA does not recommend that people stop using these medicines. Instead, a person taking antidepressants should be watched for warning signs of suicide. This is especially important at the beginning of treatment or when the doses are changed.

What to think about
These medicines may take several weeks to start working.

These medicines are generally not prescribed for people who have serious heart problems.

Nortriptyline and desipramine are more commonly used in older adults because these medicines are less likely than amitriptyline to cause constipation and to lower blood pressure.