Question:
Q. I have been diagnosed with major depression and posttraumatic stress disorder. I have taken about seven antidepressants without apparent improvement. As I look back to the periods of my life in which I was most depressed, they seem to coincide with periods in which I was feeling the most anxious. I am now on trazodone. Is it helping me primarily due to its ant anxiety effects rather than its antidepressant effects? If so, does that have anything to do with my PTSD? Also, might it be helpful to increase the dosage somewhat if I have another or prolonged relapse with depression?
Answer:
A. Depression and anxiety are very commonly entangled together, or, as psychiatrists say, commonly co-occur. Similar biological mechanisms may underlie both conditions. PTSD is considered an anxiety disorder, but is often accompanied by significant depressive symptoms. Conversely, depression is often accompanied by agitation (which may be mistaken for simple anxiety) and true anxiety symptoms, such as hyper-vigilance, over-arousal, tremor, etc. Fortunately, many of the medications we use for major depression are also effective for anxiety; e.g., Prozac, Zoloft and Serzone. Trazodone is usually effective as an antidepressant in rather high doses (greater than 300 mg/day), but may have anti anxiety effects in doses as low as 50 mg/day. Thus, it is entirely possible that it is acting mainly as an "antianxiety" agent in your case. Increasing the dosage might be helpful if you have another bout of major depression, though many people find that side effects of higher doses of trazodone (sedation, lightheadedness) limit the drug's usefulness (Dividing the dose, with most of it at bed time, may help). Have you been tried yet on trazodone's close cousin, nefazodone? It is probably more useful for mixed anxiety-depression than trazodone, for some people.
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