Schizophrenia

Question 1

How does schizophrenia affect men and women differently?

Answer 1

men
- have a higher incidence
- more likely to experience negative symptoms
- lower social functioning

women
- have a later mean age of onset
- more affective symptoms

Question 2

What are the different classes of schizophrenia?

Answer 2

positive
- hallucinations, delusions, disorganised thought/speech and movement disorders

negative
- social withdrawal, anhedonia (lack of joy/pleasure), lack of motivation, poverty of speech and emotional flatness

cognitive
- impaired working memory, impaired attention and impaired comprehension

Question 3

What are the phases of schizophrenia?

Answer 3

prodrome - late teens/twenties, often mistaken for depression or anxiety

active/acute phase - onset of positive symptoms

remission - treatment and return to normality

relapse

Question 4

What are the causes of schizophrenia?

Answer 4

genetics - candidate risk genes are gene deletions and mutations

environmental factors - pregnancy/birth complications, stress, drug use

Question 5

How can schizophrenia be diagnosed?

Answer 5

ICD 11

DSM-V

Question 6

What pathways of the brain does schizophrenia effect?

Answer 6

nigrostriatal DA pathway
- controls movement and motor function, blocking causes EPS and PD

mesolimbic DA pathway
- regulates pleasurable sensations, HYPERactivity causes positive symptoms

mesocorticol DA pathway
- cognitive and affective symptoms, HYPOactivity causes negative symptoms

tuberoinfundibular DA pathway
- controls prolactin release, blocking causes increased prolactin release

Question 7

How are antipsychotics classed?

Answer 7

1st generation
- typicals
- cause more extrapyramidal side effects at therapeutic doses
- may cause tardive dyskinesia (involuntary facial movements)
- effective against positive symptoms
- mainly antagonise D2 receptors

2nd generation
- atypicals
- usually cause no or weak EPSE at therapeutic doses
- do not usually cause TD
- effective against positive and negative symptoms
- mainly antagonise D2 and 5-HT2A receptors

Question 8

What are examples of 1st generation antipsychotics?

Answer 8

chlorpromazine, trifluoperazine
flupentixol, zuclopenthixol
haloperidol
sulpiride

Question 9

What are examples of 2nd generations?

Answer 9

aripiprazole
amisulpride
clozapine, olanzapine
paliperidone, risperidone, lurasidone
quetiapine, asenapine

Question 10

Why are antipsychotics known as dirty drugs? What are their side effects?

Answer 10

block many receptors

alpha adrenoceptors - postural hypotension, nasal congestion, hypothermia

histamine 1 - sedation/drowsiness

5-HT - weight gain, photosensitisation

muscarinic - dry mouth, blurred vision, constipation, urinary retention

D2
- tuberoinfundibular = endocrine effects due to prolactin
- nigrostriatal = movement disorder
- mesolimbic = antipsychotic effects but blocks pleasure (anhedonia)

Question 11

What are unwanted side effects of antipsychotics?

Answer 11

movement disorders

hormonal side effects - gynaecomastia, breast swelling, impotence

anticholinergic - dry mouth, blurred vision, urinary retention (micturition), constipation

weight gain/diabetes
sedation drowsiness
cardiac

EPSE - dyskinesia, tardive dyskinesia, akathisia (restlessness), parkinsonian side effects (tremor/rigidity)

Question 12

Why are anticholinergic drugs useful in schizophrenia?

Answer 12

they are beneficial in treating extrapyramidal side effects

Question 13

What is the issue with tardive dyskinesia?

Answer 13

most EPSE are dose dependent and disappear when the antipsychotic is withdrawn

TD does not usually respond to dose reduction and is irreversible

Question 14

What are the advantages and disadvantages of using clozapine?

Answer 14

rarely causes EPSE or hormonal side effects

causes weight gain and diabetes
causes cardiomyopathy and myocarditis
- need an ECG
is epileptogenic
- reduces seizure threshold
hyper salivation
- can be treated with hyoscine hydrobromide
constipation
- potentially fatal risk of intestinal obstruction, faecal impaction, and paralytic ileus
- must be treated

Question 15

What are the advantages and disadvantages of using olanzapine?

Answer 15

causes weight gain and diabetes

Question 16

What drugs causes noticeable hormonal side effects?

Answer 16

risperidone and amisulpride

Question 17

What is needed before starting haloperidol?

Answer 17

an echocardiogram (ECG) is needed
- can cause QT prolongation

Question 18

What monitoring is required for patients on antipsychotics?

Answer 18

fasting glucose
lipid profile
full blood count
liver function tests
urea and electrolytes
eGFR
weight
BMI
pulse
blood pressure
prolactin

thyroid function tests - only with quetiapine

Question 19

What is the effect of smoking on clozapine?

Answer 19

antipsychotic medication clozapine is principally metabolized by the hepatic cytochrome enzyme CYP1A2

the induction of this enzyme by tobacco smoke results in enhanced clozapine metabolism and consequently a reduction in plasma concentration

if smoking, you need higher doses of clozapine
if stopping smoking, you need to titrate clozapine dose down

Question 20

Why do people on clozapine need regular blood testing?

Answer 20

require leucocyte monitoring due to leucocytosis (rise in WBC)

require regular blood testing (FBC) due to neutropenia and potentially fatal agranulocytosis reported

Question 21

Which antipsychotics cause extrapyramidal side effects more often?

Answer 21

1st generation
- chlorpromazine, trifluoperazine
- flupentixol, zuclopenthixol
- haloperidol
- sulpiride

Question 22

Which antipsychotics cause hormonal side effects? What can they be replaced with?

Answer 22

Risperidone and amisulpride can noticeably increase serum prolactin

Aripiprazole, clozapine and quetiapine have no/minimal effect on prolactin

Question 23

Which drugs cause weight gain? What can they be replaced with?

Answer 23

Most common with clozapine and olanzapine - high risk

Medium risk with quetiapine, paliperidone and risperidone

Least likely with aripiprazole