Biological treatments Flashcards
Typical antipsychotics
First generation of drugs. Focus on dopamine in association with the dopamine hypothesis.
Atypical antipsychotics
Developed after typical- second generation. Targets dopamine, serotonin, glutamate. Reduces side effects compared to typical antipsychotics.
Example of typical antipsychotic
- chlorpromazine (1950s)
- administered orally
- 1000mg daily. Initial dose is smaller, gradually increased to maximum. Most take between 400-800mg.
How it works::
- Antagonist in dopamine system (chemical that recues action of NT).
- Blocks dopamine receptors in synapses of brain, reducing its action.
- Dopamine levels initially increase and then are reduced.
- Normalises neurotransmission in areas of the brain, reducing symptoms like hallucinations.
Side effects:
- sedative
- dizziness, agitation, sleepiness, stiff jaw, weight gain, itchy skin
- long term- tardive dyskinesia which causes involuntary facial movement (eg. lip smacking)
- neuroleptic malignant syndrome- high temperature, delirium, coma
Earlier example of atypical antipsychotics
- clozapine (1960s)
- dosage is typically 300-450 mg a day
How it works:
- binds to dopamine receptors, also acts on serotonin and glutamate receptors.
- helps improve mood and cognitive functioning, reduces anxiety and depression
- mood enhancing- can be prescribed when a patient has high suicide risk (30-50%)
Side effects:
- deaths can occur from blood condition (agranulocytosis)- meaning it is only used when other treatments fail, patients take regular tests.
Development of atypical antipsychotics example
- risperidone (1990s)
- small dose initially given. Built up to typical dose of 4-8mg daily, max 12mg
How it works:
- tablets, syrup or injection lasting two weeks.
- binds to dopamine and serotonin receptors.
- binds more strongly- effective in smaller doses.
- fewer side effects than others.
- less serious side effects than clozapine.
