IC11 Schizophrenia & Psychosis Flashcards
What is psychosis?
Psychosis is when a person is out of touch with reality
What is schizophrenia?
Schizophrenia is when a person experiences psychosis for prolonged periods of time (at least 6 months).
Schizophrenia is a more severe form of psychosis.
What are possible causes of psychosis?
- Iatrogenic causes - mistake made in treatment
- Alcohol & psychoactive substance misuse
- Mood disorders - mania, severe depression
What are the 2 main theories that can lead to schizophrenia?
It is the dysregulation of:
1. Dopaminergic (DA) functions
2. Serotonergic (5HT) functions
What are common risk factors that increases the chance of a patient developing schizophrenia?
- Genetics
- Neurodevelopmental effects
- Personality
What are possible risk factors that can cause a patient to develop schizophrenia?
- Tumour or injury
- Drug / substance-induced psychosis
What are risk factors that prolong schizophrenia in patients?
- Poor adherence to antipsychotic medication
- Lack of support
What are the criteria to diagnose a patient with schizophrenia?
A. 2 or more of the following persisting for 1 month:
- delusions
- hallucinations
- disorganized speech
- disorganized appearance OR catatonic behaviour
- negative symptoms
B. Social / occupational dysfunction
C. Continuous signs of disorder for at least 6 months (inclusive of criteria A)
D. Other possible conditions have been excluded
E. Disorder is NOT due to a medical disorder or substance use
F. If there is pervasive developmental disorder - there must be hallucinations or delusions present for at least 1 month
What should we assess for a patient suspected with schizophrenia?
- History of present illness
- Psychiatric hx
- Substance Use hx
- Medication hx
- Family, occupational hx
- Any injury or trauma
- Assess for suicidal tendencies***
- Lab tests
What are the goals of therapy in treating schizophrenia?
- Minimize threat to self & others
- Minimize acute symptoms
- Prevent relapse
- Promote medication adherence
- Optimise dose and manage ADR
- Improve QOL & function
What are non-pharmacological management treatments that we can use?
- Social support & counselling
- Individual Cognitive Behavioural Therapy (CBT)
- Electroconvulsive therapy (ECT)
- Psychosocial rehabilitation program
CBT can be considered if patient is in a listening state.
What is the main class of drug to use for schizophrenia?
Anti-psychotics
Antipsychotics help to relieve symptoms of psychosis & prevent relapse.
Long-term treatment is often necessary
Antipsychotics can be used to treat mania.
Antipsychotics can also be used together with Antidepressants for pt w Major Depression.
How can we overcome the poor adherence to anti-psychotic medications?
- Use IM long-acting injections
- Educate pt & family
- Have community nurse provide regular home visits & administer the medication.
Recall what are the 4 dopamine pathways:
- Nigrostriatal pathway
- Mesolimbic pathway
- Mesocortical pathway
- Tuberoinfundibular pathway
What are the functions of the 4 dopamine pathways?
- Nigrostriatal pathway
- Mesolimbic pathway
- Mesocortical pathway
- Tuberoinfundibular pathway
Nigrostriatal pathway:
- Nigrostriatal pathway controls movement. Blocking the dopamine receptors in the nigrostriatal pathway will lead to extrapyramidal side effects (EPS)*
Mesolimbic pathway::
- Overactivity of dopamine receptors in this region leads to positive symptoms* of schizophrenia. Main MOA of anti-psychotics is to block dopamine receptor in the mesolimbic pathway
Mesocortical pathway:
- Dopamine blockade of the mesocortical pathway will lead to negative symptoms* in schizophrenia.
Tuberoinfundibular pathway:
- Dopamine blockade in this pathway leads to hyperprolactinemia*
Blockade of the nigrostriatal, mesocortical & tuberoinfundibular pathway will lead to ADR.
Based on your knowledge of the 4 pathways, what are the effects of using dopamine antagonist?
(Name both good and bad effects)
Good effect:
- Helps to reduce positive symptoms
Bad effects:
- Extrapyramidal side effects
- Hyperprolactinemia
Based on research, dopamine antagonists are effective as antipsychotics if they block _____% of dopamine receptors.
(A) 50%
(B) 60%
(C) 70%
(D) 80%
Ans: 60%
If inhibition of dopamine receptors exceed 60%, there will be hyperprolactinemia and EPS.
Can you list out the guideline to treat and manage schizophrenia?
Upon diagnosis of schizophrenia,
1. Use a single* FGA or SGA (avoid clozapine)
2. If it doesn't work, use another single* FGA & SGA (avoid clozapine)
3. If it doesn't work, use clozapine*
4. If clozapine doesn't work, use combination therapy
- FGA + FGA
- FGA + SGA
If any of the treatment is sufficient w tolerable side effects, we can continue using the same treatment without escalating.
What are the rules to follow in the treatment guideline of schizophrenia?
1. Use a single* FGA or SGA (avoid clozapine)
2. If it doesn't work, use another single* FGA & SGA (avoid clozapine)
3. If it doesn't work, use clozapine*
4. If clozapine doesn't work, use combination therapy
- FGA + FGA
- FGA + SGA
If any of the treatment is sufficient w tolerable side effects, we can continue using the same treatment without escalating.
These are the rules to follow when using the treatment guideline:
- Medication selection is individualized
- Pt to be on a medication for at least 2-6 weeks at therapeutic doses, before we consider it as ineffective***
- Help patients to manage side effects. If intolerable, switch to another agent
- Consider long acting injectable anti-psychotics to improve compliance
- ***Only consider clozapine in treatment resistant pt that have failed ≥2 types of antipsychotics. Monitor pt on clozapine closely and regularly.
What is the most significant ADR of clozapine?
Agranulocytosis
What are adjunctive medications that we can use in:
(1) Cooperative patient
(2) Uncooperative patient
(1) Cooperative pt:
- Oral lorazepam
- Oral risperidone
(2) Uncooperative pt:
- IM lorazepam
- IM olanzapine
- IM haloperidol
What are the 3 common characteristics of oral antipsychotics?
- 1-3 hours to reach peak concentration
- Most oral antipsychotics take 1-3hrs to reach peak concentration - Long half-life
- Most oral anti-psychotics have long half-life - Drowsiness
- Most antipsychotics have drowsiness effect. Advice patient to take the medication at night.
List out first generation antipsychotics (FGA) and second generation antipsychotics (SGA).
FGA:
1. Haloperidol
- Haloperidol often comes as haloperidol decanoate, where the phenol group of the compound is esterified
SGA:
1. Clozapine
2. Quetiapine
3. Risperidone
What is the difference in terms of side effects between FGA & SGA?
In general, FGA have more SE than SGA.
- FGA has more EPS than SGA***.
- FGA has more severe hyperprolactinemia SE than SGA
- The FGA that we learn in this IC do not cause weight gain, whereas SGA medication - clozapine and olanzapine can lead to severe weight gain
All SE are dose dependent!
