Atypical depression

There are three subtypes of MDD melancholia, or classic depression atypical, or nonclassic depression and psychotic depression. These three subtypes have construct validity based on differences in the following ... 

Several subtypes of depression require specific treatment strategies that go beyond a simple course of conventional antidepressant therapy (these subtypes include bipolar depression, major depression with psychotic features, seasonal depression, atypical depression, comorbid anxiety disorder, comorbid substance abuse, double depression [major depression... 

Monoamine oxidase inhibitors are used to treat depression, atypical depression, bulimia, posttrau-matic stress reactions, obsessive-compulsive disorder, panic attacks, narcolepsy, phobias, hypochondria, anxiety, and many other psychiatric disorders as well as night tremors, parkinsonism, postural hypotension, headache, and aphthous stomatitis. 

Treatment of Major Depression. Dmgs commonly used for the treatment of depressive disorders can be classified heuristicaHy iato two main categories first-generation antidepressants with the tricycHc antidepressants (TCAs) and the irreversible, nonselective monoamine—oxidase (MAO) inhibitors, and second-generation antidepressants with the atypical antidepressants, the reversible inhibitors of monoamine—oxidase A (RIMAs), and the selective serotonin reuptake inhibitors (SSRIs). Table 4 fists the available antidepressants. 

Normally, dietary tyramine is broken down in the gastrointestinal tract by MAO and is not absorbed. In the presence of MAOI, however, all of its potent sympathomimetic actions are seen. Other side effects of MAOI include excessive CNS stimulation, orthostatic hypotension, weight gain, and in rare cases hepatotoxicity. Because the monoamine oxidase inhibitors exhibit greater toxicity, yet no greater therapeutic response than other, newer agents, clinical use has been markedly curtailed. The primary use for MAOIs is in the treatment of atypical depressions, eg, those associated with increased appetite, phobic anxiety, hypersomnolence, and fatigues, but not melancholia (2). 

Some patients present with "atypical features" of depression ... 

Each antidepressant has a response rate of approximately 60% to 80%, and no antidepressant medication or class has been reliably shown to be more efficacious than another 22 MAOIs may be the most effective therapy for atypical depression, but MAOI use continues to wane because of problematic adverse effects, dietary restrictions, and possibility of fatal drug interactions.22,28 There is some evidence that dual-action antidepressants, such as TCAs and SNRIs, may be more effective for inpatients with severe depression than are the single-action drugs such as SSRIs,22,28 but the more general assertion that multiple mechanisms of action confer efficacy advantages is quite controversial.33... 

Conventional antipsychotic drugs such as chlorpromazine and haloperidol have long been used in the treatment of acute mania. More recently, atypical antipsychotic drugs including aripiprazole, olanzapine, quetiapine, risperidone, and ziprasi-done have been approved for the treatment of bipolar mania or mixed mood episodes as monotherapy or in combination with mood-stabilizing drugs.25 Aripiprazole and olanzapine are also approved for maintenance therapy. The combination of olanzapine and fluoxetine is approved for treatment of bipolar depression. Quetiapine is approved for treatment of... 

Larsen, J. K., Gjerris, A., Holm, P. etal. Moclobemide in depression a randomized, multicentre trial against isocar-boxazide and clomipramine emphasizing atypical depression. Acta Psychiatr. Scand. 84 564-570,1991. 

Non-motor signs of the disorder are also treatable with symptomatic medications. The frequent mood disorder can be treated with standard antidepressants, including tricyclics (such as amitryptiline) or serotonin reuptake inhibitors (SSRIs, such as fluoxetine or sertraline). This treatment is not without risks in these patients, as it may trigger manic episodes or may even precipitate suicide. Anxiety responds to benzodiazepines, as well as to effective treatment of depression. Long-acting benzodiazepines are favored over short-acting ones because of the lesser abuse potential. Some of the behavioral abnormalities may respond to treatment with the neuroleptics as well. The use of atypical neuroleptics, such as clozapine is preferred over the typical neuroleptics as they may help to control dyskinesias with relatively few extrapyramidal side-effects (Ch. 54). 

Alternatively, the current antidepressant may be augmented (potentiated) by the addition of another agent (e.g., lithium, T3), or an atypical antipsychotic (e.g., risperidone). Risperidone has been shown to be effective in combination with fluvoxamine, paroxetine, or citalopram in treatment-resistant depression. Olanzapine and fluoxetine have been found to be safe and effective in treatment-resistant depression. 

There are numerous antidepressant medications on the market (table 7.1). Following development of monoamine oxidase (MAO) inhibitors were tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), and several atypical antidepressants (Baldessarini 1996). Successive generations of antidepressants have not necessarily become more effective in treating depression, but rather offer more favorable side-effect profiles—a crucial factor in effective clinical pharmacotherapy. An effective medication is not useful if its side effects are intolerable. 

Future directions for research on hypericum may continue the work done in clinical efficacy. More specifically, studies may be of interest that examine its effects in treatment of more severe depression and different subtypes of depression. The comparative efficacy of different hypericum preparations could be further investigated, and optimum dosages need to be established (Linde et al. 1996). Further work is needed to compare hypericum s efficacy and side effects with those of the SSRIs or atypical antidepressants, because published studies to date have only compared it with tricyclics. 

Trazodone (Desyrel). Trazodone was the first of the atypical antidepressants and was actually introduced prior to the SSRIs. It does not have the serious cardiac toxicity or anticholinergic side effects of the TCAs and was the most popular antidepressant until the arrival of the SSRIs. It is approved for the treatment of depression and is also commonly used in low doses to treat agitation in demented patients and insomnia. 

Mirtazapine (Remeron). Mirtazapine is the newest of the atypical antidepressants. It mainly works by blocking the alpha-2 negative feedback receptor and thus increases norepinephrine and serotonin activity. In addition, mirtazapine blocks serotonin-2 and serotonin-3 receptors to produce a specific serotonin action like nefazodone. Mirtazapine is approved for the treatment of depression. Its use in the anxiety disorders is being studied. 

The fourth factor influencing medication choice is the safety of the medication. This is especially important given the snicide potential of depressed patients. The newer antidepressants, inclnding the SSRls and so-called atypical antidepressants, are mnch safer in overdose than the older TCAs and MAOIs. In the case of the TCAs, ingestion of a 1-2 week snpply is lethal 50% of the time. 

Phases of Bipolar Illness. The depressive phase of bipolar illness is virtually indistinguishable from unipolar MDD and the diagnostic criteria for a major depressive episode (refer to Table 3.2) are used to diagnose bipolar depression as well. The clinical presentation of bipolar depression often resembles atypical depression, which is characterized by severe fatigue and oversleeping. 

It is common for both the depressive and manic phases to occur simultaneously in what is termed a mixed state or dysphoric mania. During these mixed episodes, the patient s mood is characterized by symptoms of both a depression and mania. Mixed episodes often have a poorer outcome than classic euphoric mania and, as a rule, respond better to certain anticonvulsants and atypical antipsychotic drugs than to lithium. As many as 50% of admissions to inpatient psychiatric facilities for the treatment of manic episodes appear to be for mixed manic states. The recognition... 

Another BRAD diagnostic modifier is the frequency of mood episodes or cycling. Patients who experience four or more episodes (depressed, hypomanic, or manic) per year are said to have rapid cycling BRAD. Rapid cycling patients are more likely to be female and, like those with mixed episodes, respond preferentially to certain anticonvulsants and perhaps atypical antipsychotics than to lithium. 

Loxapine (Loxitane). Loxapine is a medium potency antipsychotic, and it has several interesting features. First, it is chemically very similar to clozapine, the first of the atypical antipsychotics. In the test tube, loxapine actually behaves more like an atypical antipsychotic (more on that later), but when patients are treated with it, loxapine acts more like a traditional typical antipsychotic. A second point of interest is that loxapine is actually the major active metabolite of the antidepressant amoxa-pine (Ascendin). As a result, one can use a single medication (amoxapine) to treat both depression and psychosis. In practice, however, the use of what is essentially a fixed dose combination medication should be avoided. Using amoxapine does not allow separate adjustment of the antipsychotic and antidepressant, and most importantly, amoxapine is the only antidepressant associated with the risk of TD. 

Major Depressive Disorder (MDD) with Atypicai Features. The anhedonia of MDD is often manifested by social withdrawal. In contrast to social anxiety disorder, the social withdrawal of MDD is desired by the patient, at least during the major depressive episode, and does not persist when the episode remits. Atypical depression is characterized by another symptom reminiscent of social anxiety disorder—a longstanding pattern of sensitivity to interpersonal rejection. The interpersonal sensitivity associated with atypical depression is often characterized by stormy relationships and overly emotional responses to perceived slights. Such social lability is seldom observed in patients with social anxiety disorder. 

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