Tricyclic and tetracyclic antidepressants for depression

Examples

Tricyclic antidepressants (TCAs)

Heterocyclic antidepressants

How It Works

These medications balance certain brain chemicals (neurotransmitters) that cause depression when out of balance. When these brain chemicals are in proper balance, the symptoms of depression may be relieved.

Why It Is Used

This type of medication is used to help relieve the symptoms of major depression. These drugs may be used when other types of antidepressants have been ineffective.

When these drugs are not used

• Some of these medications are not given to older adults, because the medications cause too many negative side effects.
• Cyclic antidepressants usually are not given to people with certain heart problems, such as irregular heartbeats or low blood pressure.

How Well It Works

Like other antidepressants, cyclic antidepressants relieve depression in about 60% of people with depression.¹

Side Effects

Side effects may vary among these medications, and most of them improve as the person continues to take the medication. Cyclic antidepressants tend to have more common and more serious side effects than other, newer types of antidepressant medications, such as serotonin reuptake inhibitors (SSRIs). Side effects include:

• Stomach upset and other digestive problems, such as constipation.
• Dry mouth, blurred vision, and/or drowsiness.
• Lowered blood pressure.
• Weight gain.
• Tremors and sweating.
• Inability to urinate (urinary retention).
• Sexual dysfunction.
• Confusion or delirium, in older adults.
• Fatigue.

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 medications need to be started at low doses, and the dose should be increased gradually to reduce the severity of side effects. Regular blood tests may be needed to check the amount of the medication in your blood. Too much of this type of medication in the bloodstream can be dangerous.

Do not suddenly stop taking these medications. If you decide to stop taking your antidepressant, you will need to lower your dose slowly, with your doctor's help.

You may start to feel better within 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.

Desipramine and nortriptyline have the fewest side effects and may be given to older adults for this reason. However, these medications may not be the preferred choice for treatment of depression in older adults, due to the severity of the side effects.

You may need to be hospitalized until these medications are working, especially if you are feeling suicidal, because it is possible to overdose on this type of medication.

Tricyclic antidepressants (TCAs) and heterocyclic medications are not usually used with some heart medicines, such as digoxin (Lanoxin), and some seizure medicines, such as phenytoin (Dilantin). Make sure your doctor has a complete list of all the medicines you are taking.

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