Clinical uses
Schizophrenia
Clozapine is usually used for people diagnosed with schizophrenia who have had an inadequate response to other antipsychotics or who have been unable to tolerate other drugs due to extrapyramidal side effects. It is also used for the treatment of psychosis in Parkinsons Disease. It is regarded as the gold-standard treatment when other medication has been insufficiently effective and its use is recommended by multiple international treatment guidelines, supported by systematic reviews and meta-analysis. Whilst all current guidelines reserve clozapine to individuals when two other antipsychotics evidence indicates that clozapine might be used as a second line drug. Clozapine treatment has been demonstrated to produced improved outcomes in multiple domains including; a reduced risk of hospitalisation, a reduced risk of drug discontinuation, a reduction in overall symptoms and has improved efficacy in the treatment of positive psychotic symptoms of schizophrenia. Despite a range of side effects patients report good levels of satisfaction and long term adherence is favourable compared to other antipsychotics. Very long term follow-up studies reveal multiple benefits in terms of reduced mortality, with a particularly strong effect for reduced death by suicide, clozapine is the only antipsychotic known to have an effect reducing the risk of suicide or attempted suicide. Clozapine has a significant anti-aggressive effect. Clozapine is widely used in secure and forensic mental health settings where improvements in aggression, shortened admission and reductions in restrictive practice such as seclusion have been found.
The sympathetic nervous system also stimulates the skeletal system and muscular system to pump more blood to those areas to handle the acute stress. Simultaneously, the sympathetic nervous system inhibits the digestive system and the urinary system to optimise blood flow to the heart, lungs, and skeletal muscles. This plays a role in the alarm reaction stage. The parasympathetic response is colloquially known as the "rest and digest" response, indicated by reduced heart and respiration rates, and, more obviously, by a temporary loss of consciousness if the system is fired at a rapid rate. The parasympathetic nervous system stimulates the digestive system and urinary system to send more blood to those systems to increase the process of digestion. To do this, it must inhibit the cardiovascular system and respiratory system to optimise blood flow to the digestive tract, causing low heart and respiratory rates. The parasympathetic nervous system plays no role in acute stress response.Studies have shown that patients with acute stress disorder have overactive right amygdalae and prefrontal cortices; both structures are involved in the fear-processing pathway. Diagnosis
According to the DSM-V, symptom presentation must last for three consecutive days to be classified as acute stress disorder. If symptoms persist past one month, the diagnosis of PTSD is explored. There must be a clear temporal connection between the impact of an exceptional stressor and the onset of symptoms; onset is usually within a few minutes or days but may occur up to one month after the stressor.