Antipsychotics -Guided learning Flashcards
What are the psychotic disorders? What are the main features of psychosis?
Psychotic disorders are a spectrum of disorders, includes schizophrenia and associated disorders (Schizotypal and delusional disorders). In all there is a distorted perception of reality, and a minimum set of symptoms- delusions and hallucinations.
What are the 4 main features of a psychotic episode?
1) Disrupted thought patterns 2) lack of self awareness 3) delusion 4) hallucination
What is schizophrenia?
Defined by ICD10 as being characterised by distortions of thinking, perception and affect that is inappropriate or blunted. (Affect = emotional response to stimuli).
What does a schizophrenia diagnosis require?
Distortion in thinking, perception and affect that is blunted or inappropriate. Disturbance must last for 6 months or longer with at least one month of classical symptoms. Classical symptoms: 1) delusions –> unshakable false/ impossible beliefs or ideas 2) hallucinations –> perception in absence of external stimuli 3) disorganised/ catatonic behaviour 4) Negative symptoms (4 A’s)
What are the 4 A’s of schizophrenia? What type of symptoms are they?
4 A’s: Avolition/ Apathy- (Lack of motivation to initiate/ perform self directed purposeful activities) Anhedonia- inability to feel pleasure during normally pleasurable activities Alogia - Lack or paucity (insufficient amount) of speech Affective blunting - both good and bad moods are dampened).
What are the 5 dimensions of symptoms shown by schizophrenic sufferers?
Dont PANiC: - Depression and anxiety -Positive symptoms -Agressive symptoms -Negative symptoms -Cognitive symptoms
What pathway do the antipsychotic drugs act on?
Antipsychotics act to modulate the DA pathway.
How many classes of antipsychotic drugs are there?
1st generation antipsychotics –> selective dopamine D2 R antagonist 2nd generation antipsychotics –> both serotonin and DA antagonists 3rd generation –> aripiprazole
Fill out the following table:
What is DA involved in generally?
- DA involved in:
- fine tuning of motor control
- fine tuning of mood
- reward pathways
- pleasure
what disorders is a disruption in DA assocaited with?
- Schizophrenia
- Parkinsons
- Psychosis
What hallucinations are common in schizophrenia?
What delusions are common?
- Auditory hallucinations are common in schizphrenia. These hallucinations tend to be in 3rd person like at external voice giving them direction or commenting on their behaviour
- Delusions tend to persecutory in nature, hallucinations tend to be auditory and 3rd person
What are some classical symptoms of Schizophrenia based around:
Thoughts?
Delusions?
Hallucinations?
The 4 A’s?
Behaviour and speech?
- Thoughts:
- Thought insertion/ withdrawal –> belief that thoughts are being inserted or removed by an external force
- Thought echo –> hearing ones own thoughts spoken aloud
- Thought broadcasting –> belief that others can hear your thoughts
- Disorder of thoughts
- Delusions:
- Delusions of control –> idea that 3rd party controls thoughts/ feelings/ actions/ impulses
- Delusional perception –> “ red cars mean I’m going to die.”
- Hallucinations:
- Auditory –> often 3rd person, discussing patient’s behaviour
- 4 A’s:
- apathy/ avolition
- alogia
- affective blunting
- anhedonia
- Behaviour and speech –> Exaggerated or disorganised
What is the aetiology of schizophrenia?
- Increase in DA in the mesolimbic pathway, treated with antidopaminergic drugs which is seen to improve the condition
- Structural changes: Reduced blood flow to frontal lobes and basal ganglia, atrophy of grey matter particularly in medial temporal lobes, enlarged ventricles.
What is the treatment for Schizophrenic disorders?
What are some of the problems of pharmacological treatment?
- Pharmacological –> 1st ad 2nd generation antipsychotics and psychological therapy
- 1st generation: Haloperidol and chlorpromazine
- 2nd generation: amisulpride, risperidone, clozapine
- Problems of antipsychotic treatment is it has less effect on negative symptoms, 60% still suffer these symptoms
- Other problem: extrapyramidal effects –> 2nd generation has less
What are the 4 main dopamine pathways in the brain?
- Mesocortical:
- From ventral tegmental area (VTA) of midbrain and Substantia Nigra (SN) –> Nucleus Accumbens –> Cortex. part. pre frontal cortex (Personality expression)
- Mesolimbic:
- From VTA/ SN –> Nucleus Accumbens –> Limbic system (frontal/ parietal/ temporal lobes)
- Tuberohypophyseal:
- From HypoT –> Pituitary gland –> Controls the release of Prolactin
- Nigrostriatal:
- From SN –> Basal ganglia –> fine tune and control motor function
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What is part of the extrapyramidal system?
- Basal ganglia
- reticulospinal tract
- rubrospinal tract
- tectospinal
- vestibulospinal
What is a risk of long term 1st generation antipsychotic use?
What are the symptoms of this risk?
How would you alter treatment?
- Risk of long term 1st generation antipsychotics –> tardive dyskinesia
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Tardive dyskinesia is characterised by:
- disabling involuntary movements including:
- choreiform movements
- grimacing and twisting of the face and limbs
- tongue protrusion
- disabling involuntary movements including:
- Tardive dyskinesia can be irreversible, difficult to treat, can remit
- Change to 2nd generation and remove any anticholinergic drugs
What is neuroleptic malignant syndrome?
- Neuroleptic malignant syndrome is a rapid onset of extreme side effects due to genetic polymorphism of D2 receptor
- Presents within weeks:
- Hyperthermia / fever
- Tachycardia (autonomic problems)
- incontinence (autonomic problems)
- altered conciousness
Fill out the following table for hyper and hypokinetic disorders
Dystonia –> abnormal muscle tone resulting in muscular spasm and abnormal posture
Choreoathetosis –> irregulat migrating contractions and writhing movements
Huntingtons disease results from degeneration of the striatum
Which two nuclei form the striatum
What effect does D2 antagonism have on the indirect pathway and therefore why might this be useful for treating hyperkinetic disorder?
- The striatum is formed of the putamen and caudate nucleus
- Normally the indirect pathway:
- Striatum –] GPE —] Subthalamic nucleus —> GPI and SNPR —] Thalamus —> motor cortex —> corticospinal tracts –> muscles
- In huntingtons degeneration of the striatum leads to loss of inhibition of GPE, this now inhibits STN so that it cannot active the GPI/SNPR which now cannot inhibit the thalamus. –> overactive movements
- D2 antagonism prevents inhibition of the striatum from the SNPC. Striatum able to inhibit movement, prevents hyperkinetic disorder.
