Antipsychotic agents therapeutic indications

Examples abound regarding the role of serendipity in the discovery of new therapeutic approaches, which on closer examination usually turned out to be the result of clinicians paying attention to unexpected clinical effects rather than discounting them. For example, lithium was tried first for hypertension, chlorpro-mazine was initially developed as an anesthetic, and imipramine was originally regarded as an antihistamine and an antipsychotic agent. Without astute clinical observations, these drugs would not have found their niche, nor would clozapine have been revived for the benefit of millions of the most difficult to treat schizophrenic patients. Other examples include the expanded indications of newer... 

Indications and use. Lithium carbonate is effective treatment in > 75% of episodes of acute mania or hypomania. Because its therapeutic action takes 2-3 weeks to develop, lithium is generally used in combination with a benzodiazepine such as lorazepam or diazepam (or with an antipsychotic agent where there are also psychotic features). 

While large interindividual variability in the steady-state plasma concentrations among patients treated with similar doses of a given antipsychotic is well established, the existence of a critical range of plasma concentration for therapeutic response or significant adverse effects remains controversial. A body of data from a number of fixed-dose studies, however, indicates a possible threshold for response or a linear or curvilinear relationship between plasma levels and clinical response for agents such as ... 

I Sedation and Cognition. Sedation must be recognized as an antipsychotic side effect and not as an indication of therapeutic effect. It occurs more frequently with antipsychotics with antihistaminic properties. Chlorpromazine, thioridazine, mesoridazine, clozapine, olanzapine, and quetiapine are most frequently implicated. Administration of most or all of the daily dosage at bedtime (depending on the drug half-life) can decrease daytime sedation and in some patients eliminate the need for hypnotic agents. Sedation occurs early in treatment... 

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