2. Biological treatment of Schizophrenia

Question 1

Anti-Psychotics

Answer 1

All anti-psychotic drugs have an antagonist effect on dopamine D2 receptors (they block the receptor reducing its activity). Reduced dopamine activity will therefore mean less activity in the mesolimbic pathway and therefore a decrease in positive symptom of SZ.

Question 2

Typical antipsychotics

Answer 2

These were introduced in the 50’s to calm the patient down and reduce positive symptoms, they bind to the D2 receptors and prevent dopamine from entering the synapses permanently. As D2 receptors are also involved in motor control a very common side effect is movement problems e.g. tremors, repetitive movements, uncontrolled movements.

It can:

• Work on positive symptoms
• Lead to more movement side effects

Question 3

Atypical Anti-psychotics

Answer 3

Atypical antipsychotics (such as clozapine) also block the action of dopamine by binding to D2 dopamine receptors so that they block dopamine being absorbed by the brain however rather than permanently blocking the receptors, they will only temporarily occupy dopamine receptors. This should result in less movement side effects. Other neurotransmitters are also involved in the atypical antipsychotics, mainly serotonin.

It can:

• Work on positive & negative symptoms
• Lead to less movement side effects

Question 4

Strengths (3)

Answer 4

• It is an effective treatment – Tiihonen et al (2017) found that was in the top 3 most effective treatments for reducing relapse in a cohort study of 29,823 Sz patients.
• It is effective on treatment resistant patients – Kane (1988) – 30% patients who had not experienced relief from symptoms using 3 different anti-psychotics previously showed marked reduction in symptoms compared to 4% for chlorpromazine.
• Less movement side effects than typical antipsychotic drugs

Question 5

Weakness

Answer 5

• Side effects eg lack of sleep and weight gain