We take a slight detour. A late Oct blog entry to Robert Whitaker's "Mad in America" contained this intriguing title: Do Antidepressants Worsen the Long-term Course of Depression? ...
The piece extracted some of the main points from a review article by Giovanni Fava of the University of Bologna. Here is Whitaker's summation:
- After six months of antidepressant treatment, the drugs "generally fail to protect" against a return of depressive symptoms. (In other words, maintenance treatment is ineffective, compared to placebo.)
- Two-thirds of patients maintained on antidepressants suffer from "residual symptoms," with "anxiety, insomnia, fatigue, cognitive impairment, and irritability the most commonly reported."
- As patients are switched from one antidepressant to another or to a polypharmacy regimen, their illness may be propelled "into a refractory phase, characterized by low remission, high relapse and high intolerance."
- Antidepressants increase the risk of a "switch" into mania, and thus into bipolar illness. Antidepressants also increase the risk that bipolar patients will become rapid cyclers, and that bipolar patients will develop a syndrome dubbed "Chronic Irritable Dysphoria."
It was suggested that long-term use of antidepressant drugs may increase, in some cases, the biochemical vulnerability to depression and worsen its long-term outcome and symptomatic expression, decreasing both its likelihood of subsequent response to pharmacological treatment and the duration of symptom-free periods.
In summing up, he notes:
When we prolong treatment over 6–9months we may recruit processes that oppose the initial acute effects of antidepressant drugs (loss of clinical effects). We may also propel the illness to a malignant and treatment-unresponsive course that may take the form of resistance or episode acceleration. When drug treatment ends, these processes may be unopposed and yield withdrawal symptoms and increased vulnerability to relapse. Such processes are not necessarily reversible. The more we switch or potentiate antidepressant drugs the more likely is oppositional tolerance to take place.
But there is this important qualifier:
The phenomena we have described, however, are difficult to interpret unless a precise diagnostic categorization of mood disturbances is made, taking into consideration both their longitudinal course, the unipolar/bipolar distinction and their subtypes.
Dang! Nuances again.
Next: A look at the nuances ...