L20: Schizophrenia And Antipsychotic Drugs

Question 1

What does schizophrenia mean

Answer 1

Divided mind

Question 2

What are the clinical features of patients with schizophrenia

Answer 2

• Diagnosis in adolescence/ early adulthood
• You can see repeated episodes and then a recovery before another break happens
  Or
  Chronic with a progressive decline

Question 3

What can the symptoms of schizophrenia be divided into

Answer 3

Positive (type 1) and negative (type2) symptoms

Question 4

What are positive symptoms

Answer 4

Presence of abnormal thought and behaviour on top of normal behaviour hence it is positive (extra)

Question 5

What are the positive symptoms according to DSM 5

Answer 5

• delusions
• auditory hallucinations
• disorganised speech
• grossly disorganised or catatonic behaviour

Question 6

What are negative symptoms

Answer 6

The absence of behaviour or responses

Question 7

What are the negative symptoms according to the DSM 5

Answer 7

• Reduced expression of emotion

- social withdrawal

Question 8

Which symptom makes it harder to notice and diagnose schizophrenia

Answer 8

Negative symptoms

Question 9

What happens to the risk of schizophrenia when there is a first degree relative with schizophrenia

Answer 9

Increases

Question 10

What other factors increases the risk of schizophrenia

Answer 10

The environment:

• slow viral infection
• autoimmune process
• poor maternal nutrition
• developmental abnormality

Question 11

What is the hypothesis called that suggests an explanation to schizophrenia

Answer 11

Dopamine hypothesis

Question 12

What does the dopamine hypothesis state

Answer 12

That the dopaminergic hyperactivity underlies schizophrenia

Question 13

What evidence has led to the dopamine hypothesis

Answer 13

Evidence from drugs

Question 14

What are the 3 drugs that have led to the dopamine hypothesis

Answer 14

• amphetamine
• D2 receptor agonist
• L-dopa

Question 15

How does amphetamine work

Answer 15

Releases dopamine in the brain

Question 16

When there is too much amphetamine what does this lead to

Answer 16

Toxic psyhosis:
Paranoid delusions
Visual or auditory hallucinations
Compulsive behaviour

Question 17

What are the toxic psychosis symptoms called

Answer 17

Type 1 like symptoms in non schizophrenia

Question 18

What can happen to the positive symptoms if someone with schizophrenia takes amphetamine

Answer 18

Exacerbate positive symptoms

Question 19

What type of symptoms do D2 receptor agonist increase

Answer 19

Type 1 like symptoms

Question 20

Overall what does the dopamine hypothesis suggest

Answer 20

Increase in dopamine transmission can exacerbate type 1 symptoms

Question 21

What was the first drug discovered as an anti-psychotic drug

Answer 21

Chlorpromazine

Question 22

What symptoms does chlorpromazine reduce

Answer 22

Positive symptoms

Question 23

What is another effect of chlorpromazine

Answer 23

Sedation i.e decreased irritability

Question 24

What group of drug is chlorpromazine part of

Answer 24

Typical neuroleptics

Question 25

What is neuroleptics the same as

Answer 25

Anti-schizophrenic Anti-psychotic Major tranquilliser (All mean the same as neuroleptic)

Question 26

What are the main 3 classes of typical neuroleptics

Answer 26

Phenothiazine Butyrophenones Thiozanthines

Question 27

Name an example of a phenothiazine

Answer 27

Chlorpromazine

Question 28

Name an example of butyrophenones

Answer 28

Haloperidol

Question 29

Name an example of thioxanthines

Answer 29

Flupenthixol

Question 30

What are typical neuroleptics known as

Answer 30

Dirty drugs

Question 31

What is the mechanism of action of typical neuroleptics

Answer 31

Receptor antagonists of: - d1 and d2 for dopamine - ach mucarinic receptors - histamine receptors - noradrenaline alpha receptors - 5HT receptors

Question 32

Which symptoms are typical neuroleptics are good at treating

Answer 32

Positive symptoms

Question 33

What are atypical neuroleptics

Answer 33

Receptor antagonist that are more selective i.e not dirty drugs Show fewer motor side effects

Question 34

What are atypical neuroleptics good at treating

Answer 34

Negative symptoms | Treatment resistant schizophrenia i.e when treatment doesn’t work

Question 35

Which atypical neuroleptic drugs are good at targeting D2 receptors

Answer 35

Sulpiride | Amisulpride

Question 36

What are the classes of atypical neuroleptics

Answer 36

Selective d2 receptor antagonist Multi acting receptor targeted agents Serotonin dopamine antagonist Novel type

Question 37

Name example of drugs that are multi acting receptor targeted agents

Answer 37

Clozapine | Alanzapine

Question 38

Name examples of drugs that are serotonin-dopamine antagonists

Answer 38

Reperidone Zotepine Sertindole

Question 39

Name example of drugs that are novel type

Answer 39

Quetiadipine

Question 40

Which pathway in the brain results in positive symptoms

Answer 40

Mesolimbic pathway due to hyper function

Question 41

Which pathway in the brain results in negative symptoms

Answer 41

Mesocortical pathway due to hypo function

Question 42

What are the 2 main reasons for getting side effects of anti-psychotic drugs

Answer 42

- Blocking dopamine receptors | - Blocking other receptors

Question 43

What are the 3 broad side effects due to targeting dopamine receptors

Answer 43

1) anti-emetic 2) increased prolactin release 3) extrapyramidal motor symptoms

Question 44

What do we get an anti-emetic effect

Answer 44

Due to D2 receptor block in the chemoreceptor trigger zone and histamine receptor block

Question 45

What does anti-emetic mean

Answer 45

Decrease in nausea and vomiting

Question 46

Why do we get an increased prolactin release

Answer 46

1) In normal circumstances dopamine inhibits prolactin release from the pituitary gland 2) when we block the dopamine receptors (D2) on the pituitary gland this causes the release of prolactin

Question 47

What does increased prolactin release cause as a side effect

Answer 47

Breast swelling Pain Lactation

Question 48

What are the 2 types of extra-pyramidal motor symptoms that can occur

Answer 48

Acute: dystonias Chronic: tardive dyskinesia

Question 49

Why do we get extra-pyramidal motor symptoms

Answer 49

Due to blockade of nigra-striata pathway involved for normal movement Striatum that has dopamine receptors become blocked in the basal ganglia

Question 50

What are dystonias

Answer 50

- Involuntary movement of the face, neck and tongue | - Parkinsonian: tremor at rest, muscle rigidity, decreased mobility

Question 51

What is tardive dyskinesia

Answer 51

Involuntary movement of the face, tongue, limbs and trunk | It is slowly developing with long term use

Question 52

What are the 3 main broad side effects caused by blocking other receptors with neuroleptic drugs

Answer 52

- anti muscarinic effect: dry mouth, constipation, visual disturbance - postural hypertension due to alpha adrenoceptor block - sedation due to histamine receptor block

Question 53

What is the problem with the dopamine hypothesis

Answer 53

- Neuroleptic drugs takes weeks to be effective which suggests the treatment is giving secondary effects to be effective - typical drugs are not good for negative symptoms, hypothesis is too simple and there is evidence that under activity of dopaminergic signalling from the mesocortical pathway leads to negative symptoms. Whereas the dopamine hypothesis suggests an over activity of dopaminergic pathway.