Schizophrenia Flashcards
What symptoms are present in schizophrenia?
Schneider's first rank symptoms: Auditory hallucinations Persecutory delusions Control delusions Though broadcasting, echo, insertion and withdrawal
Positive symptoms: Hallucinations of other modalities Catatonia Neologisms Tangential speech
Negative symptoms: Anhedonia Marked apathy Blunting of responses Poverty of speech
What are other causes of psychosis besides schizophrenia?
Organic causes of psychosis:
Delirium
Dementia
Temporal lobe epilepsy
Infections of the CNS e.g. AIDs, neurosyphilis, encephalitis
Brain injury
Brain tumours
Huntington’s disease
Metabolic disorders e.g. Vitamin B12 deficiency, porphyria
Endocrine disorders e.g. Cushing’s syndrome, thyroid disease (Hyperthyroidism, thyroid storm)
Medication effects e.g. high dose steroids
Autoimmune disorders e.g. lupus, thyroid disease (Hashimoto’s disease)
Psychiatric causes of psychosis: Drug-induced schizophrenia Severe depression - nihilistic delusions Bipolar disease Schizoaffective disorder
What neurological pathway produces positive and first-ranked symptoms?
Mesolimbic - too much dopamine leads to these symptoms
Typical antipsychotics target this pathway
What neurological pathway produces negative symptoms?
Mesocortical - too little dopamine
Atypical antipsychotics target this pathway
What side effect profile do antipsychotics?
Metabolic (weight gain, hyperglycaemia, hypercholestrolemia)
Extrapyramidal (Parkinsonism, akathisia, tardive dyskinesia and dystonia) - more common in typical
Cardiovascular (prolonged QT)
Hormonal (increased plasma prolactin) - hyperprolactinaemia more common in atypical
Neuroleptic malignant syndrome (NMS)
Others: Postural hypotension Nausea and vomiting Constipation Hypersalivation Dry mouth Sedation Blurred vision Seizures
What baseline tests need to be recorded prior to starting antipsychotic medication?
Weight
Waist circumference
HR and BP
Bloods - FBCs, LFTs (for transaminitis), fasting blood glucose, HbA1c, lipid profile, prolactin
Assess for any movement disorders
Assess nutritional status, diet and level of physical activity
ECG
What is the mechanism of action of typical antipsychotics?
Work as D2 receptor antagonist:
The high potency typical antipsychotics bind with a high affinity to D2, therefore have a higher risk of extrapyramidal side effects
e.g. haloperidol, sulpiride, amisulipiride
The low potency typical antipsychotics can interact with non-dopaminergic receptors resulting in more cardio toxic and anticholinergic side effects e.g. chlorpromazine
What is the mechanism of action of atypical antipsychotics?
Block serotonin and dopamine
Examples of atypical antipsychotics: Amisulpride Risperidone - dose-dependent ESPE's Olanzapine Quetiapine Aripiprazole Clozapine
What side effects are associated with clozapine?
Agranulocytosis and neutropenia Reduced seizure threshold Constipation Myocarditis Hypersalivation
Which class of antipsychotics is associated with an increased risk of stroke and VTE?
Atypical antipsychotics
What are the symptoms of dystonia and how is it treated?
Symptoms: Muscle spasms (oculogyric crisis, torticollis, dysphagia, dysarthria)
Treatment:
Procyclidine
Anticholinergics e.g. benzotropine, diphenhydramine
What are the symptoms of akathisia and how is it treated?
Symptoms:
Inner restlessness and compulsion to move
Associated with increased risk of suicide
Treatment: Reduce antipsychotic Swap to atypical Propranolol Clonazepam Clonidine
What are the symptoms of pseudo-parkinsonism and how is it treated?
Symptoms:
Parkinsonism
Bradyphrenia
Treatment: Procyclidine Anticholinergics Propranolol Dopamine facilitator e.g. amantadine
What are the symptoms of tardive dyskinesia and how is it treated?
Symptoms: Lip smacking Tongue protrusion Choreiform hand movements Pelvic thrusting
Treatment: Reduce antipsychotics Stop anticholinergic Tetrabenazine (a depressogenic) Clonazepam Propranolol
What is neuroleptic malignant syndrome (NMS) and how is it treated?
Symptoms: Autonomic dysfunction (hyperthermia, hypertension, tachycardia, hyperreflexia, tremor, agitation, irritability, sweating) Stiffness High fever Confusion
Treatment: Stop antipsychotic ICU Active cooling - for hyperthermia IV fluids to prevent renal failure Dantrolene, bromocriptine or amantadine can be used for rigidity Benzodiazepine for agitations
