Atypical neuroleptic malignant syndrome: diagnostic controversies and considerations.

Neuroleptic malignant syndrome (NMS) is a serious and potentially fatal adverse effect of antipsychotic drugs. The diagnosis of NMS commonly requires core symptoms of hyperthermia and muscle rigidity. Although diagnostic criteria for NMS have been established and are widely accepted and used, it should be recognized that atypical presentations pose a diagnostic dilemma, as hyperthermia and/or muscle rigidity may be absent or develop slowly over several days, leading to impairment or a significant delay in diagnosis and treatment. Evidence from case reports and retrospective evaluations supports a concept of atypical NMS, particularly with regard to treatment with atypical antipsychotics. However, it remains unclear whether these atypical presentations represent early or impending NMS. Furthermore, it is unclear whether dysfunction in other neurotransmitter systems, in addition to dopamine, may be involved in the pathogenesis of NMS induced by atypical antipsychotics. In patients receiving any antipsychotic, clinicians should carefully evaluate any features of NMS and should not prematurely exclude a diagnosis of NMS in cases where severe rigidity or hyperthermia is not initially apparent.

Antidepressants and suicidal behavior in bipolar disorder.

Patients with bipolar disorder are at very high risk for suicidal ideation, non-fatal suicidal behaviors and suicide and are frequently treated with antidepressants. However, no prospective, randomized, controlled study specifically evaluating an antidepressant on suicidality in bipolar disorder has yet been completed. Indeed, antidepressants have not yet been shown to reduce suicide attempts or suicide in depressive disorders and may increase suicidal behavior in pediatric, and possibly adult, major depressive disorder. Available data on the effects of antidepressants on suicidality in bipolar disorder are mixed. Considerable research indicates that mixed states are associated with suicidality and that antidepressants, especially when administered as monotherapy, are associated with both suicidality and manic conversion. In contrast, growing research suggests that antidepressants administered in combination with mood stabilizers may reduce depressive symptoms in patients with bipolar depression. Further, the only prospective, long-term study evaluating antidepressant treatment and mortality in bipolar disorder, although open-label, found antidepressants and/or antipsychotics in combination with lithium, but not lithium alone, reduced suicide in bipolar and unipolar patients (Angst F, et al. J Affect Disord 2002: 68: 167-181). We conclude that antidepressants may induce suicidality in a subset of persons with depressive (and probably anxious) presentations; that this induction may represent a form of manic conversion, and hence a bipolar phenotype, and that lithium's therapeutic properties may include the ability to prevent antidepressant-induced suicidality.