L6 Drug Therapy for SZ

Question 1

What are Typical Anti-Psychotic drugs?

Answer 1

• These drugs act as dopamine antagonists by binding to D2 receptors in the mesolimbic dopamine pathway in the brain
• Used to reduce the positive symptoms of SZ such as delusions and hallucinations caused by high dopamine levels
• The drugs must bind to 60-75% of the D2 receptors and block their activity to be effective

Question 2

What are some examples of Typical Anti-Psychotic drugs and what form do they come in?

Answer 2

• Examples are Chlorpromazine, Phenothiazine and Thorazine
• Drugs are available as tablet, syrup or injection

Question 3

What are Strengths of Typical Anti-Psychotic drugs? (2)

Answer 3

Cheap to produce
- They are effective treatments of symptoms of SZ and are cheap to produce
- This allow patients to live a normal life outside of institutional care
- 97% of SZ patients are able to live at home because of these drugs

Marder (1996)
- Found evidence to back up the fact that typical anti-psychotics are effective at dealing with positive symptoms of SZ, e.g hallucinations and delusions
- However he did find that they do not have any effect on the negative symptoms, e.g apathy and speech poverty

Question 4

What are Weaknesses of Typical Anti-Psychotic drugs? (2)

Answer 4

Tardive dyskinesia - side effects
- These drugs have a terrible set of side effects e.g dizziness, agitation sleepiness, stiff jaw, weight gain etc
- Long term patients may develop tardive dyskinesia, whereby mouth muscles and their chin make involuntary movements

• Extra pyramidal side effects
  
  • This side effect causes dysfunction in the nerve tracts from the brain and spinal motor neurons
  • The SZ patient might develop side effects that resemble Parkinson’s disease, e.g tremors in the fingers, drooling and muscular rigidity

Question 5

What are Atypical Anti-Psychotic drugs?

Answer 5

• These drugs block the activity of dopamine within the brain by acting on D2 receptors to reduce dopamine
• These drugs temporarily occupy D2 receptors and then allow dopamine transmission
• They also work to increase serotonin activity in the brain and bind to serotonin receptors to improve mood
• These have fewer side effects than typical drugs, they work to reduce both positive and negative symptoms of SZ

Question 6

What are two examples of Atypical Anti-Psychotic Drugs

Answer 6

Clozapine and Risperidone

Question 7

What are Strengths of Atypical Anti-Psychotic drugs? (2)

Answer 7

• Proven to be the most effective treatment
• Typical and atypical drugs have their strengths in that they are the most effective treatment
• When compared to any other form of therapy available for treating SZ, in terms of both biological and psychological
• Meltzer (2012)
  
  • Conducted research in support of Clozapine being the more effective drug for treating SZ
  • Clozapine was found to be 30-50% more effective in minimising SZ symptoms compared to typical drugs

Question 8

What are Weaknesses of Atypical Anti-Psychotic drugs? (2)

Answer 8

• Side Effect ‘Agranulocytosis’
  
  • A side effect of Clozapine, a blood condition
  • This is were he bone marrow is affected and less white blood cells are produced, which can affect immunity to illness
• Treats symptoms, not the cause?
  
  • Drug therapy has the disadvantage that it treats the symptoms of SZ, not the cause of it
  • Symptoms might return if the patient stops taking drugs creating the ‘revolving door phenomenon’