Methods of modifying 1 - Anti-psychotics Flashcards
(20 cards)
How do antipsychotics generally work?
They work by altering the levels of dopamine levels within the brain.
What was the first anti-psychotic to be developed?
Chlorpromazine, they weren’t sure how it worked but noticed it reduced psychotic symptoms.
What is an Agonist?
Activates receptors to produce a response, it binds to a receptor and activates it to produce a response.
What is an Antagonist?
Blocks or dampens an activator receptor, it binds to the receptor but doesn’t activate it. Works well when levels are too high.
What are the first generation of antipsychotics known as?
Conventional antipsychotics.
How do conventional anti psychotics work?
They act as an antagonist and bind to D2 receptor sites to reduce the levels of dopamine within the system.
How does the ‘blocking’ action work?
The presynaptic neurone fires dopamine as usually into the synapse, however it can not reach the post synaptic neurone as this is blocked by the conventional anti-psychotic. Initially the presynaptic neurone increases dopamine levels to make up for this however it soon becomes depleted leaving a substantial decrease in overall levels.
How do conventional anti-psychotics reduce symptyoms?
It reduces dopamine levels in the mesolimbic system therefore reducing positive symptoms such as hallucinations.
What are the more recent anti-psychotics called?
A-typical antipsychotics
How do a-typical antipsychotics work?
They are a partial antagonist, they find areas in the brain with increased activity and attach to reduce activity but no block completely. In areas where to dopamine is too low it acts to boost the levels of dopamine activity.
Example of A-typical antipsychotics?
Risperidone
How does risperidone work?
It acts as a dopamine antagonist where levels are too high to decrease them and as a serotonin antagonist where levels are to low.
Differences between Conventional and A-typical?
- Conventional act as dopamine antagonist for all areas of the branding meaning they may block receptors unnecessarily reducing functions such as motor control.
- A typical anti-psychotics are dopamine and serotonin antagonists meaning levels may actually be balanced out when taken.
Evaluation - Effectiveness of conventional anti-psychotics
Cole et al conducted study one these, he found that psychiatric disorders could be treated using drugs and found that 75% of those given a conventional anti-psychotic were considered to be more improved than those of a placebo control group. None of them got worse b ut did in control group.
Evaluation - Cloazpaine effectiveness
Lobos found that clozapine was effective in reducing symptoms compared to other atypical antipsychotics but the side effects left many people dropping out. It is often paired with another anti-psychotic but limited evidence for this effectiveness.
Evaluation - Revolving door of psychiatry
More often than not people are given anti-psychotics when admitted to hospital before being discharged. Therefore they find it difficult to adhere to the strict schedule. This affects the research published on effectiveness and must be treated with caution when being used for long term purposes. A study found that in 63,000 cases of schizophrenics prescribed anti-psychotics 40% of the population had poor adherence.
Evaluation - Ethical implications. Side effects
Both anti-psychotics have side effects such as Parkinsonianism. Psychologists must consider if the benefits are worth the potential costs of side effects. When first prescribed patients may be in chronic episode and therefore may not be able to give valid consent meaning they may not want these side effects.
Evaluation - Chemical straitjackets
Anti-psychotics are argued as a method to keep people quiet and under control. Was suggested that treating mental illness physically is believing in demonology, it was a way of excluding non conformists from society. Proposed the ethical issue whether they are given for patient benefit or to increase compliance with society.
Evaluation Social implications - Asylums or care in the community
This caused a great shift in society from the idea that schizophrenia ruined an individuals life and could only be treated in an institution to something that could be treated externally and lead to better quality of life and less hospitalisation.
Evaluation Social Implications - Risk of violence
One serious consequence of individuals who do not adhere to drug programme is that they may become a threat to themselves or the society. Higher risk of suicicde and homicide by people with schizophrenic history, most of them had stopped their treatment of drugs.
