antipsychotics - schizophrenia Flashcards
2 types of antipsychotics?
- typical antipsychotics - first generation developed in 1950s
- atypical antipsychotics - newer generation developed during the 90s
how do typical antipsychotics work?
work by blocking the action of dopamine at the synapse therefore acting as a blocking agent reducing the firing of neurons
- blocks D2 receptos. presynaptic neuron releases dopamine to synapse as the receptor sites on the postsynaptic neuron are blocked by the drug this reduces the firing. initially causing more dopamine to be released into the synapse however the production of dopamine eventually decreases.
typical antipsychotics helps what symptoms of SZ?
reduces positive symptoms as it blocks the action of dopamine in the limbic system and cerebral cortex (areas associated with emotion and organised thoughts)
side effects of typical antipsychotics?
can cause patients to experience tremors and slowing of motor movements
how do Atypical antipsychotics work?
works by attaching to D2 dopamine receptors having a temporary effect as well as not binding so readily ad they have a lower affinity for D2 but bind readily to D3 +D4 which is restricted to neurons of the limbic system and cerebral cortex meaning actions of these antipsychotics is confined to areas involved with SZ symptoms.
what symptoms does Atypical antipsychotics Treat?
both negative and positive symptoms as it has a blocking effect on both serotonin and dopamine
which antipsychotics are preferred and why?
Atypical are heavily preferred as they have less side effects. Hill found 30% of people using typical experience involuntary movement of lips and tongue which is 75% irreversible
3 effectiveness points?
- effectiveness of typical
- effectiveness of atypical
- difficulty assessing effectiveness
effectiveness of typical antipsychotics?
Jonathan Cole et al - found 75% of those given antipsychotics were considered to be ‘much improved’ compared to 25% give a placebo. none of the patients given antipsychotics were considered to have gotten worse in comparison to 48% of those given a placebo
effectiveness of Atypical antipsychotics?
considered more effective than typical. Ravanic et al - found over a 5 year period of comparing the difference, there was a significant difference in psychometric scores measuring SZ symptoms, favouring atypical. as it had less side effects however some respond better to typical so it shouldn’t be made redundant.
difficulty in assessing effectiveness?
some patients are in denial about their conditions thinking they’re perfectly normal, causing them to not take their medication making it harder to assess effectiveness. Rettenbacher found full compliance in only 54.2% of SZ, partial compliance in 8.3% and non compliance in 37.5% of cases suggesting they may not be as effective as they seem.
2 ethical issues?
- side effects
- chemical straitjackets
side effects - ethical issue ?
both types have side effects such as Parkinson’s as a result the psychiatrist has to consider whether the benefits outweigh the potential costs of side effects. when individuals first diagnosed with SZ antipsychotics may be administered without their valid consent .
chemical straitjackets?
antipsychiatry movement claims AS just keep people quiet and under control. Szasz - argued using physical treatments for mental disorders is no more than believing in demonology. he suggested the concept od mental illness was simply excluding non-conformists from society. highlighting an ethical dilemma of whether AS are prescribed to alleviate suffering or increase compliance with institutional regimes
2 social implications?
- living a normal life
- risk of violence
living a normal life?
Lawrie says AS has changed SZ from being seen as incurable and shown it can be treated in the community with the potential for independent living and recovery. this benefits the patient as they can lead to a more normal life and also benefits society due to drop in costs of a lifetime hospitalisations
risk of violence?
one consequence of SZ that don’t follow drug therapy is they may pose a threat to themselves or others. Tilhonen noted a 37 fold increase in suicide in patients who stopped taking medication. the NCISH reported 346 homocides have been committed in England by people with a history of SZ between 2003 and 2013 which was 6% of the homocide rate
