Tricyclic antidepressants for chronic pain

Examples

---

Brand Name	Chemical Name
Endep	amitriptyline

Brand Name	Chemical Name
Norpramin	desipramine

Brand Name	Chemical Name
Sinequan	doxepin

Brand Name	Chemical Name
Tofranil	imipramine

Brand Name	Chemical Name
Pamelor	nortriptyline

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.¹

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.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

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.

Complete the new medication information form (PDF) (What is a PDF document?) to help you understand this medication.

References

---

Citations

1. Fields HL, Martin JB (2005). Pain: Pathophysiology and management. In DL Kasper et al., eds., Harrison's Principles of Internal Medicine, 16th ed., vol. 1, pp. 71–76. New York: McGraw-Hill.

Credits

---

Author	Shannon Erstad, MBA/MPH
Editor	Kathleen M. Ariss, MS
Associate Editor	Pat Truman
Primary Medical Reviewer	Adam Husney, MD - Family Medicine
Primary Medical Reviewer	Kathleen Romito, MD - Family Medicine
Specialist Medical Reviewer	Nancy Greenwald, MD - Physical Medicine and Rehabilitation
Last Updated	February 22, 2007