Depression is a serious mood disorder marked by prolonged feelings of sadness and despair. Although researchers haven’t discovered the exact cause of depression, several brain chemicals are linked to mood disorders, including dopamine, norepinephrine and serotonin.
As a treatment for depression, tricyclic antidepressants (TCAs) increase levels of these neurotransmitters in the brain.
Tricyclic Antidepressant Medications
The first tricyclic treatment for depression was imipramine, released in 1958. Swiss scientists originally created imipramine as a potential treatment for schizophrenia, but it didn’t achieve its intended result (imipramine actually exacerbates schizophrenia symptoms). They discovered, however, that imipramine was an effective treatment for depression.
As a treatment for depression, tricyclic antidepressant drugs block certain nerve cells in the brain from absorbing too much serotonin, dopamine and norepinephrine. They are called tricyclic because of their three-ring chemical structure. Commonly prescribed tricyclic antidepressants include:
- Amitriptyline (ElavilÂ®, EndepÂ®, EmitripÂ®, EnovilÂ®)
- Amoxapine (AsendinÂ®)
- Clomipramine (AnafranilÂ®)
- Desipramine (NormpaminÂ®, PertofraneÂ®)
- Doxepin (AdapinÂ®, SinequanÂ®)
- Imipramine (JanimineÂ®, TipramineÂ®, TofranilÂ®)
- Maprotiline (LudiomilÂ®)
- Nortriptyline (PamelorÂ®, AventylÂ®)
- Protriptyline (VivactilÂ®).
Strengths and Weaknesses of Tricyclic Antidepressant Drugs
Although each person responds differently to antidepressant drugs, tricyclic antidepressants are often more successful at treating depression than other antidepressant medications. This may be because they target several brain chemicals, instead of just serotonin. For many years, tricyclic antidepressant drugs were the first course of treatment for depression.
However, tricyclic antidepressants can also cause severe side effects. While they increase the levels of mood-related neurotransmitters, these antidepressant medications also interfere with many unrelated neurotransmitter systems and brain cell receptors, sometimes causing:
- Blurred vision
- Disorientation or confusion
- Dry mouth
- Elevated risk of heart attack
- Increased appetite
- Increased heart rate
- Low blood pressure
- Sensitivity to sunlight
- Sexual problems
- Urinary retention
- Weight gain.
Who Shouldn’t Take These Antidepressant Medications?
Alcohol can be toxic when mixed with tricyclic antidepressants. In addition, people with schizophrenia or bipolar disorder should avoid tricyclic antidepressant drugs, which may worsen their symptoms. TCA antidepressant medications may also cause complications in people with an enlarged prostate, diabetes, glaucoma or heart disease.
Because of the severe side effects associated with tricyclic antidepressants, milder antidepressant medications, such as SSRIs, are often the first course of treatment. If these medications fail, tricyclics may be successful at relieving depression symptoms.
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Depression Guide. (2005). Tricyclic antidepressant. Retrieved June 8, 2010, from http://www.depression-guide.com/tricyclic-antidepressant.htm.
Mayo Clinic. (2008). Tricyclic antidepressants (TCAs). Retrieved June 8, 2010, from http://www.mayoclinic.com/health/antidepressants/MH00071.
Ross-Flanigan, N. (2002). Antidepressants, tricyclic. Retrieved June 8, 2010, from http://www.healthline.com/galecontent/antidepressants-tricyclic.