Posted by TSA West on March 12, 2002, at 18:05:09
In reply to Re: Relapse, Taper Effects or Possible Misdiagnosis? » AnneL, posted by TSA West on March 12, 2002, at 12:25:42
I will post the content of the article since the link doesn't seem to be working:
"Sir: The antidepressant profile of venlafaxine includes a broad range of clinical activity, as its effect is not influenced by factors such as the presence of melancholic features, age, gender, severity, or duration of depression.1 A recent analysis of the treatments of major depression revealed that venlafaxine had the highest efficacy rates and lowest dropout rates when compared with tricyclics and serotonin reuptake inhibitors.2 Up to one third of patients with rigorously defined treatment-resistant depression show a favorable response to venlafaxine, but nearly half of these patients are unable to sustain the antidepressant effect during the first 3 months of treatment.3 I present the case of a woman who was unable to sustain antidepressant response for more than 4 months following 2 separate trials of venlafaxine, but showed, on both occasions, an excellent response when rechallenged with venlafaxine after a2-week washout period.
Case report. Ms. A, a 28-year-old married woman, had a 9-year history of major depression with underlying dysthymia, and panic disorder with phobic avoidance behavior. Before initiation of venlafaxine, she had failed to respond to adequate trials of imipramine, clomipramine, amitriptyline, phenelzine, isocarboxazid, fluoxetine, sertraline, and nefazodone. Augmentation strategies with the addition of lithium, liothyronine sodium, and the combination of sertraline and amitriptyline were also unsuccessful. Similarly, she did not show a favorable response to a course of bilateral electroconvulsive therapy. Despite receiving trials of benzodiazepines, such as alprazolam in a daily dose of 1.5 mg, and valproic acid, Ms. A continued to experience rather frequent and severe panic attacks, which resulted in a marked reduction in her activities outside the home. Ms. A self-medicated with alcohol during the early part of the illness, but had been abstinent for several years before the initial trial of venlafaxine. In spite of requiring at least a dozen hospitalizations and complying regularly with the prescribed medications, Ms. A had remained highly symptomatic. The family history was positive for major depression and panic disorder in first-degree relatives, and a distant relative on her mother's side of the family had committed suicide. There was no personal or family history of bipolar illness.
Ms. A showed a rather robust response to the addition of venlafaxine, up to 262.5 mg/day, to lithium, 750 mg/day, diazepam, 15 mg/day, and methotrimeprazine, 25 mg/day. Not only did she experience a complete resolution of symptoms after 1 month of treatment, but there was also a marked improvement in her level of functioning. She was able to return to school after a hiatus of several years and was extremely pleased with her academic performance. The improvement was sustained for only 4 months, however, and over the next few months, Ms. A experienced a relapse of depression that included intense thoughts of suicide. She failed to respond to a higher daily dose (300 mg) of venlafaxine. Following a 2-week washout period during a hospitalization, venlafaxine was recommenced. Once again, she showed an excellent response to a daily dose of 262.5 mg, but unfortunately the symptoms of depression and anxiety reappeared after 4 to 5 months of treatment. She had no response when the venlafaxine dose was increased to 375 mg. Her condition continued to deteriorate, and she required rehospitalization. The doses of other psychotropic medications were kept the same, and the lithium level was in the therapeutic range. Venlafaxine was once again discontinued and then restarted after a 2-week washout period, this time titrated to a daily dose of 187.5 mg. Ms. A has been symptom free for 9 months but remains highly apprehensive about experiencing yet another relapse.
This patient suffered from a long history of treatment-resistant depression with nonresponse to adequate trials of various antidepressant drugs from different classes and electroconvulsive therapy as well as augmentation strategies. This makes it unlikely that the periods of improvement following trials of venlafaxine were related to placebo effect4 or spontaneous remissions. It is also unlikely that this is a case of antidepressant drug-induced cycling as suggested by Wehr.5 There was no cycling in response to past trials of antidepressant drugs; instead, the prior course of the illness was marked by pervasive treatment-resistant depression.
Loss of antidepressant response has been described in relation to various antidepressant drugs, including monoamine oxidase inhibitors and tricyclics.6-8 Various strategies, including increasing the dose to the level of tolerability, substitution with another antidepressant drug, and decreasing the dosage of drug, have been suggested. Several hypotheses have been put forward to explain this apparent loss of antidepressant efficacy.9
Given the clinical and heuristic implications of this observation, systematic studies are needed to further our understanding of loss of response to antidepressant drugs in certain patients."
poster:TSA West
thread:97544
URL: http://www.dr-bob.org/babble/20020307/msgs/97672.html