SCHIZOPHRENIA - Biological therapies for schizophrenia

Question 1

What is the most common treatment for schizophrenia?

Answer 1

Antipsychotic drugs ( short-term or long-term)

Question 2

What are the two types of antipsychotic drugs?

Answer 2

Typical/atypical

Question 3

What are typical antipsychotics?

Answer 3

• 1st generation of drugs for schizophrenia and other psychotic disorders
• since 1950
• work as dopamine antagonists
  E.g. chlorpromazine

Question 4

What are dopamine antagonists?

Answer 4

Reduces the action of neurotransmitters = blocks dopamine receptors and synapses of brain = reducing neurotransmitter action.

Initially, when individual starts taking chlorpromazine dopamine levels buildup but production is reduced = this reduces symptoms like hallucination.

Question 5

What are the sedation effects of chlorpromazine?

Answer 5

It is believed to have an effect on histamine receptors = used to calm individuals
e.g hospital patients with anxiety

Question 6

What are atypical antipsychotic?

Answer 6

Drugs for schizophrenia developed after typical antipsychotics
- Target a range of neurotransmitters such as dopamine and serotonin
eg Clozapine and Risperidone

Question 7

What is clozapine?

Answer 7

• developed 1960
• withdrawn during 1970s due to deaths of some patients from a blood condition called agranulocytosis
• remarked 1980
• 300 to 450 mg a day

Question 8

How does clozapine work?

Answer 8

• binds to dopamine receptors and acts on a serotonin and glutamate receptors
• improves mood and reduces depression and anxiety
• improves cognitive functioning

Question 9

Why is clozapine prescribed to some people?

Answer 9

Prescribed when an individual is considered at high risk of suicide.
Mood-enhancing effects of clozapine allows this risk to be reduced.

Question 10

What is risperidone?

Answer 10

• recently developed antipsychotic 1990s
• like clozapine but no serious side effects
• tablet syrup or injection
• 4 to 8 mg
• maximum 12 mg
• works like clozapine but binds to dopamine receptors more strongly, therefore more effective in smaller doses.

Question 11

Give strengths of biological therapies for schizophrenia.

Answer 11

+ evidence for effectiveness
Typical antipsychotics = Thornley et al (2003) = compared effects of chloroprocaine to control conditions in which patients received a placebo = data showed that chlorpromazine was better as associated with better functioning compared to placebo.
Atypical antipsychotics = Meltzer (2012) = concluded that clozapine is more effective in 50% of treatments.

+ antipsychotics have been used in a hospitals to calm down patient distressed by hallucinations and delusions = allows them to feel better and to engage with other treatments such as CBT.

Question 12

Give limitations of biological therapies for schizophrenia.

Answer 12

• serious side effects
  Typical antipsychotics associated with side-effects such as: dizziness, agitation, sleepiness, stiff draw, weight gain, itchy skin.
  Long-term use of typical antipsychotics = tardive dyskinesia ( involuntary facial movements such as blinking lip-smacking)

Serious side effects = neurolytic malignant syndrome = caused due to drugs blocking the dopamine action in the hypothalamus
This means antipsychotics can do harm as well as good.

• the mechanism is unclear
  The dopamine hypothesis is contradicted by the fact that dopamine levels in other parts of the brain are too low, which could cause symptoms of schizophrenia. If this is true, most antipsychotics shouldn’t work = this means some antipsychotics may not be the best treatment to opt for.