biological therapy for schizoprenia

• typical antipsychotics:

  • Chlorpromazine is also used as an effective sedative to calm patients with schizophrenia and other conditions. Thought to act on histamine receptors, hence sedative.
  • Chlorpromazine can be taken as tablets, syrup (esp when used as sedative) or by injection and typical prescribed doses have declined over the past 50 years.
• atypical antipsychotics:

  • Newer drug (70s) to improve effectiveness of drugs but minimise side effects. 
  • Clozapine was initially withdrawn in 70’s due to deaths from blood condition (agranulocytosis) but remarketed in 80’s.

  Clozapine binds to dopamine receptors just like Chlorpromazine but also acts on serotonin and glutamate receptors so reduces depression and anxiety in patients and it may improve cognitive functioning.
• atypical antipsychotics:

  • Mood-enhancing effects so sometimes prescribed when a patient is considered high risk of suicide (30-50% attempt suicide).
  • Risperidone (90’s) was developed to produce a drug as effective as Clozapine but without its serious side effects.
  • Binds much more strongly to dopamine and serotonin receptors than Clozapine so more effective in smaller doses. Some evidence that it leads to fewer side effects.
• +research support Thornley 2003 meta-analysis compared chlorpromazine to placebos across 13 trials and 1121 pps. Researchers found better functioning in patients on chlorpromazine and reduced symptom severity. but argued that not all patients respond well to typical antipsychotics, as a result, Meltzer 2003 compared Clozapine to typical antipsychotic medications and found that it was effective for 30-50% of treatment resistant cases. It also demonstrates that there are alternative and effective treatments available (atypicals) when the first method of treatment (typicals) is not effective.
• -unable to know how work. current understanding of how they work associated with orginal da hypothesis, not complete explanation for sz, and in some explanation such as updated da hypothesisda levels are low. if this is true then most antipsychotics would not work as they are made for high da levels, leading to questioning the effectiveness of these antipsychotics adding to the argument that they are ineffective
• -side effects. Typical antipsychotics cause extrapyramidal symptoms which include tardive dyskinesia, akathisia and parkinsonism. These are involuntary movements caused by damage to basal ganglia. Atypical antipsychotics do not cause EPS but instead lead to metabolic problems including weight gain, diabetes and cardiovascular disease. This has led to concerns about their long term use.