Psychotic Disorders and the Mental Health Act (DONE) Flashcards
Psychotic disorders
Psychosis is a symptom of the mind under severe stress. It can be caused by lack of sleep, physical illness, induced by drugs, or psychiatric illness
During a period of psychosis, a person’s thoughts and perceptions are disturbed and the individual may have difficulty understanding what is real and what is not.
Schizophrenia is a syndrome of these symptoms
Schizophrenia
A chronic, relapsing, severe mental illness affecting 1% of the population
Originally described as dementia of early life, progressive disintegration of personality and the relationship between self and world
Characterised by a prodrome (social isolation, loss of interest) followed by distortions of thinking and perception (positive symptoms), and inappropriate or blunted affect and cognitive symptoms (negative symptoms)
Disease classification and diagnosis based on:
ICD 10 in UK
DSM-5 in USA
Schizophrenia diagnosis
ICD 10 based on at least one of: thought interference, delusions of control, auditory hallucinations, persistent delusions being completely impossible
Or at least two of: hallucinations with delusions/overvalued ideas, disorganised speech, catatonic behaviour, negative symptoms, significant change in personal behaviour and personality
Duration of one month or greater
Delusions
An unshakeable, false belief, based on a mistake interpretation of reality inconsistent with the person’s cultural background
Hallucinations
A perception in the absence of an external stimulus
May be: auditory, visual, olfactory, tactile or gustatory
Auditory hallucinations
May present as: running commentary- voice or voices giving a description of a person’s actions; command- voice or voices giving instructions or orders
Thought interference: broadcasting, withdrawal, interference
Negative symptoms
Blunted affect Social withdrawal Avolition Poverty of speech Cognitive defects
Aetiology of schizophrenia
Biological factors: genetics, obstetric complications, neurochemical and structural abnormalities
Environmental/psychological factors: urban areas/socioeconomic status, seasonality of births, migration, life events and background stressors, cannabis and other drug use
Dopamine theory
Increased mesolimbic dopamine transmission mediates positive symptoms of schizophrenia
Based on the observations that: amphetamine increases dopamine transmission and is associated with positive symptoms; antipsychotics are dopamine antagonists
Negative symptoms may result from reduced dopaminergic activity in the prefrontal cortex
Role of glutamate
Abnormalities in glutamate activity may underlie other neurochemical changes
Ketamine and phencyclidine can induce both positive and negative symptoms of schizophrenia
Recent imaging studies have revealed increased glutamatergic (but not dopaminergic) activity in patients unresponsive to antipsychotic treatment
Prognosis of schizophrenia
Variable but generally life long, associated with physical illness, self harm, suicide and victimisation. Life expectancy reduced by about 10 years.
1/3 recover, 1/3 improve but with significant impairment, 1/3 patients require frequent hospitalisation
Prognosis better in traditional societies
Prognosis worsened in: early onset, male gender, poor premorbid/cognitive functioning, poor insight, social isolation/adversity
Treatment of schizophrenia
Assessment- ruling out non-psychiatric causes of psychosis e.g. delirium, emcephalitis
Psychological interventions- psychoeducation, CBT for psychosis, voice hearing groups. family work
Social interventions: occupational therapy, housing, employment, supported accommodation
Biological: antipsychotic medication
Antipsychotics
Typical: older, produce greater motor side effects, hyperprolactinaemia, prolonged QTc, D2 receptor antagonists
Atypical: newer, les motor side effects, greater metabolic side effects, D2/5HT receptor antagonists
Before initiation need baseline observations- weight, BP, HR, glucose, lipids, prolactin and ECG
Typical antipsychotics
Potent D2R antagonists: benperidol, pipothiazine, haloperidol, pimozide, fluphenazine
Moderatley potent D2R antagonists: chlorpromazine, perphenazine, trifluoperazine ,zuclopentixol, pericyazine
All antagonise a variety of receptors
Adverse effects mediated through antagonism of H1, ACh M, noradrenergic alpha 1, 5HT, K+ ion channel
Extra-pyramidal side effects
Movement disorders
Cause by disruption in dopaminergic transmission in nigrostriatal pathway
Pseudo-Parkinsonsim: tremor, rigidity, dribbling, treat with anticholinergic e.g. procyclidine
Akathisia: restlessness, linked to suicide, treat with beta blockers, 5HT2C antagonists or BZDs
Dystonia: involuntary muscle contraction, oculogyric crisis, torticollis, treat with anticholinergic
Tardive dyskinesia: involuntary muscle movements, tongue rolling, lip smacking, treat with gradual dose reduction/tetrabenazine
Other side effects of antipsychotics
Sedation Sexual dysfunction, hypotension Dry mouth, constipation Raised prolactin levels QT prolongation Weight gain Reduced seizure threshold Neuroleptic malignant syndrome
Examples of atypical antipsychotics
Amisulpride Aripiprazole Clozapine Quetiapine Olanzapine Risperidone/paliperidone Lurasidone
What is atypicality?
Reduced incidence of EPSE- broader therapeutic index
Possibly due to 5HT2a receptor antagonism- 5HT modulates dopamine release, fast dissociation at D2 receptor
But: risperidone and olanzapine cause EPSE at higher doses despite 100% 5HT receptor occupancy
Possibly the pharmacology of some atypicals confers benefit vs cognitive symtpoms
Dopamine D2/5HT2a receptor antagonists
Risperidone- most affinity for D2 receptors
Olanzapine- metabolic side effects
Quetiapine- least affinity, less EPSE
Long acting injections
Non-compliance with anti-psychotics is a significant problem in practice- due to lack of insight, adverse effects, symptomatology, major factor in relapse
LAIs reduce covert non-compliance
Older drugs formulated as oily injections- release the drug over weeks/months, initial test dose followed by 2-4 weekly maintenance dosing, after stopping release of drug occurs for up to 3 months
Newer antipsychotics now available and use different methods of controlled release
Aripiprazole
Licensed for schizophrenia, mania, bipolar disorder
Partial agonist at dopamine D2 receptor
Side effects: nausea, agitation, akathisia, some EPSE but may reverse prolactin elevation and weight gain associated with other drugs
May be useful for alerting properties
Oro-dispersible, liquid, IM formulations
Limitations of antipsychotics
All act primarily on dopamine receptors
Approximately 30% of patients will not respond
However, treatments with alternative pharmacologies have been disappointing
Clozapine
Different binding profile from any other antipsychotic, has relatively low affinity fro D2 receptors in the striatum and high affinity for D4 receptors in frontal cortex and 5HT receptors
Used for resistant schizophrenia- two failed treatments with other antipsychotics, one of which should be atypical
Approximately 1/3 of patients will respond at 6 weeks
Approximately 2/3 of patients will respond at one year
Clozapine- FBC monitoring
Mandatory, risk of agranulocytosis
Drug company records WBC, NC, platelets, eosinophils- initially weekly for 18 weeks, then fortnightly, then monthly after first year of treatment; monitor for one month post discontinuation
Traffic light system: green is fine, amber requires additional monitoring (two per week), red- stop immediately
Clozapine- common side effects
Hypersalivation Constipation Sedation Weight gain Hypotension/hypertension Tachycardia Fever Seizures
Neuroleptic malignant sydrome
Rare but potentially fatal side effect of all antipsychotics-
Hyperthermia, fluctuating level of consciousness, muscle rigidity, autonomic dysfunction
Associated with change in dose or formulation or initiating new medication using combinations of antipsychotic medications
Mental health act
Section 2- can be kept in hospital for up to 28 days
Can be detained if: have a mental disorder (not drug or alcohol addiction), need to be in for an assessment, to protect self or others
Section 3- can be detained in hospital for treatment for up to 6 months
Section 5(4) nurse holding powers up to 6 hours
Section 5(2) doctors holding powers up to 72 hours
