schizophrenia Flashcards
symptoms of schizophrenia
positive symptoms - delusions, hallucinations, thought disorder
negative - anhedonia, blunted affect, poverty of speech, avolition, asociality, social withdrawal
social/occupational dysfunction - continuous for 6 months
define and describe pathophysiology of SCZ
SCZ - psychotic disorder involves impaired thinking/emotions - many models describing cause
genetic cause
NT abnormality model:
- abnormality of dopamine receptors esp D2 receptors
- excessive dopamine in limbic region of brain
- because dopamine receptor antagonists make effective antipsychotics and drugs that increase dopamine (amphetamines) induce psychosis
also SCZ involves serotonin - olanzapine impacts 5HT2/D2 receptors
diagnosis of SCZ
follow diagnostic criteria of DSM IV and ICD-10 - common symptoms
- awkward social behaviour
- appear withdrawn
- vague speech/poverty of thought
- mood abnormality, depression, euphoria
- auditory hallucinations
what are NICE guidelines in SCZ
no 1st line treatment
treatment depends on individual patient, degree of sedation required, cardiac, extrapyramidal effects etc.
start low dose, slowly titrate up within dose range of BNF
- usually start atypical antipsychotic, adjust dose according to response and tolerability - assess over 6-8 weeks
if not effective - switch to typical
or another typical
if not effective - CLOZAPINE
drugs used in SCZ
typical antipsychotics
- haloperidol
- chlorpromazine
- prochlorperazine
atypical
- olanzapine
- clozapine
- quietapine
- risperidone
difference b/w typicals and atypicals
typicals - used when positive symptoms dominate as have little effect on negative symptoms
antipsychotic action correlates to dopamine receptor blockade in thalamus and limbic area- leads to extrapyramidal side effects (EPSE).
the more potent the typical - the more EPSE
atypicals - used when negative symptoms dominate, same effect on positive as typicals
clozapine - lower suicide risk, acts to block 5HT more than D2
what to do in treatment resistant SCZ
offer clozapine if patient is unresponsive to 2 other antipsychotics that have been given - at least 1 being a non-clozapine atypical
FBC must be done before starting clozapine - as it is known to cause agranulocytosis (reduced WBCs, increased risk of infection)
- monitor blood counts every week for 18 weeks, then every 2 weeks upto a year
if still not responsive - augment with another antipsychotic
complications and S.E. of antipsychotics
cardiac S.E. - QTC prolongation, torsades de pointes
EPSE - extra pyramidal side effects
NMS - neuroleptic malignant syndrome
Explain NMS and treatment
all antipsychotics can cause NMS but like EPSE - it is more common in typicals
NMS can be fatal symptoms are - fever, tachycardia, elevated creatine kinase (indicates muscle breakdown), leukocytosis (elevated WBCs)
treat with dopaminergic (bromocriptine) and cholinergic agents (procyclidine) and BDZ (dantrolene)
explain EPSE and treatment
dystonia - sustained muscle contraction - muscle spasms in head and neck
- uncontrolled rolling upwards of eyes
- treat with procyclidine
pseudo parkinsonism
- motor incoordination
- tolerate symptoms
akathisia - restlessness and anxiety
- treat with propranolol
tardive dyskinesia - weird movements of jaw and face, grimacing facial expressions
- treat by stopping anticholinergic, reduce dose of antipsychotic, change to atypical
explain hyperprolactinaemia
dopamine inhibits prolactin which causes milk production
- dopamine antagonist increases prolactin - increases milk
- most common with chlorpromazine
can manifest in many ways:
- amenorrhreoa - irregular periods
- galactorrheoa - breast milk production
- gynaecomastia - painful enlarged breasts
- sexual dysfunction - reduced libido, impotence
important S.E of clozapine and things to monitor
constipation
pneumonia
myocarditis
seizures
pancytopaenia - monitor: WBC, platelets, neutrophils
what monitoring is required
urea and electrolytes
FBC
prolactin
plasma glucose
weight
ECG
blood pressure
blood lipids
