Antipsychotic drugs antipsychotics subjective effects

Table 3.5 Effects of antipsychotic drugs in healthy subjects...

Antipsychotic drugs with strong sedative clinical effects (e.g. chlorpromazine. clozapine, olanzapine) produce subjective and objective sedation and impair most areas of performance in healthy volunteers, usually at doses far below those typically used in patients. Antipsychotic drugs with little sedative clinical action (e.g. pimozide, sulpiride, amisulpride) produce few subjective and objective effects in healthy... 

Most antipsychotic drugs cause unpleasant subjective effects in nonpsychotic individuals. The mild to severe EPS, including akathisia, sleepiness, restlessness, and autonomic effects are unlike any associated with more familiar sedatives or hypnotics. Nevertheless, low doses of some of these drugs, particularly quetiapine, are used to promote sleep onset and maintenance, although there is no approved indication for such usage. 

Most antipsychotic drugs have effects on the heart as a consequence of their pharmacological actions. Recently, thioridazine has been subjected to a restricted indication notice and the atypical antipsychotic sertindole had its licence withdrawn because of concerns about its potential cardiotoxicity. 

Voruganti, L., Cortese, L., Oyewumi, L., Cernovsky, Z., Zirul, S., 8c Awad, A. (2000). Comparative evaluation of conventional and novel antipsychotic drugs with reference to their subjective tolerability, side-effect profile and impact on quality of life. Schizophrenia Research, 43, 135-145. 

In 16 patients with treatment-resistant schizophrenia (defined as non-responsiveness to at least three antipsychotic drugs from at least two different chemical classes), olanzapine was effective treatment in a significant proportion no serious adverse events were associated with maintenance doses of 10-40 mg/day, and no subjects dropped out (26). 

It is unquestionable that current antipsychotic therapy is comparatively effective and at the same time disappointingly insufficient. These drugs can treat the symptoms of the disorder but certainly do not provide a cure. The great majority of patients will have between 20 and 50% reduction in symptom severity. Some will have marked improvement beyond these figures, although this is rare, and a small minority of patients will be entirely refractory to all forms of treatment currently available. Full results from antipsychotic therapy take considerable time (although initial effects on some positive symptoms can be seen in a few days). Whereas the effect of benzodiazepines on anxiety and sleep can be measured in hours, and that of antidepressants in weeks, the full impact of antipsychotic therapy is measured in months. A study by Robinson et al. (1999) showed that only 20% of patients responded after 4 weeks of treatment with conventional antipsychotics, whereas after 26 weeks the number of responders had grown to about 70%. Similar results were reported with clozapine treatment, where a response was observed in 40% of subjects after 4 weeks and in 60% of subjects by week 17 (Kane et al., 2001). Clinical observations clearly show that improvement in... 

These interactions impair the performance of tasks that require attention and quick reflexes (e.g. driving motor vehicles and using machinery or sharp instruments). It is necessary to warn consumers in order to prevent injury to themselves and others. Similar CNS effects can occur if subjects are taking antidepressants or antipsychotic drugs - the concurrent consumption of alcohol could be disastrous. 

Activity at the 5HT-2 receptor is an important feature of many atypical antipsychotic drugs (e.g., risperidone, olanzapine, sertindole), but the body of knowledge on 5HT-2 ligands in anxiety is more limited (173). Nonselective 5HT-2 antagonists, such as ritanserin (112), mianserin (113), and ketanserin (114), have been shown to produce anxiolytic effects in less than half of the preclinical studies conducted (202). The clinical data for ritanserin in human subjects are likewise inconclusive (458, 459). The mixed results obtained with... 

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