Aetiology and biological treatment of psychosis Flashcards
Genetics
Relatives of affected subjects have increased risk of psychosis
Environmental/ biological stress
Obstetric complications increase risk
- premature birth
- low birth weight
- perinatal hypoxia
Intrauterine infection
Antepartum bleeding
Immune activation
Macro neurodevelopmental abnormalities reported in schizophrenia
Ventricular enlargement
Widening cortical sulci
Cortical grey matter loss
Loss of asymmetry
Decreased limbic structure and thalamic volume
Progressive deficits in some
Micro neurodevelopmental abnormalities reported in schizophrenia
Cortical glial loss
Increased neurone density
Aberrant neurone migration
Synaptic loss
Decreased dendritic complexity
Neuropsychology abnormalities: deficits
Attention
Arousal
Working memory
Executive function
Eye movement
Social cognition
Theory of mind
Loss of functional asymmetry
Receptive language function
Subtle motor function
Drugs associated with psychosis influence
L-Dopa
Amphetamines
LSD
Cannabis
Cocaine
Ketamine
MDMA
PCP
Other novel psychoactives
Affective psychosis
Bipolar disorder
Depressive psychosis
Schizoaffective disorder
Organic psychosis
Epilepsy
Infections
Cerebral trauma
Cerebrovascular disease
Demyelination
Neurodevelopmental disorders
Endocrine
Metabolic
Immunological
Drugs
Toxins
Dementias
Differential diagnosis of psychosis
Affective psychosis
Organic psychosis
Personality disorder§
Physical treatments
Drugs
- clozapine has greatest efficacy in resistant cases
- treatment benefit usually clinically evident by 2 weeks
- side effects predicted by receptor affinity for drug
D2 receptor adverse effect
Dopamine
Parkinsoism
Tardive dyskinesia
Raised prolactin
5-HT2 receptor adverse effect
Serotonin
Alpha-1 receptor adverse effect
Norepinephrine
Postural hypotension
H1 receptor adverse effect
Histamine
Sedation
Weight gain
M1 receptor adverse effect
Cholinergic
Antagonism
- constipation
- urinary retention
- blurred vision
- confusion
Agonism
- saliva overproduction
Typical antipsychotics
Haloperidol
Chlorpromazine
Atypical antipsychotics
Amisulpride
Aripiprazole
Clozapine
Risperidone
Olanzapine
Quetiapine
Lurasidone
Long acting injections
Depixol
Clopixol
Piportil
Paloperidone
Aripiprazole
Typical antipsychotic side effects
Sedation
Extrapyramidal symptoms
Cardiac (hypotenesion, arrhythmias)
Temperature dysregulation
Neuroepileptic malignant syndrome
Anticholinergic side effects
Weight gain
Raised prolactin
Extrapyramidal symptoms
Parkinsonian symptoms
Dystonia
Akathisia
Tardive dyskinesia
Atypical antipsychotic side effects
Sedation
Metabolic (weight gain, glucose intolerance, increase triglycerides)
Raised prolactin (galatorrhoea, decrease sexual function, osteoporosis)
Cardiac (hypotension, arrhythmias)
Neutropaenia with clozapine
NICE guidelines for antipsychotic use
Joint choice of drug with patient/ carer/ Dr
use clozapine if no response to 2 others
Long acting injections useful in those who prefer, or help to convert non adherence
Develop advance directives
Avoid high dose or prescription of two antipsychotics together
Clozapine
Oral medication taken daily
Licensed with regular neutrophil monitoring
Neutropaenia in approx 1% of cases
Slow titration to optimal dose with monitoring of pulse, BP and neutrophil count necessary
Little parkinsonian effects or tardive dyskinesia
Sedation, weight gain, dribbling common
Electroconvulsive treatment
Not a primary treatment of psychosis
Very effective in psychosis associated with depression or with catatonia
