Antipsychotics Flashcards
What is psychosis?
Different perception of reality from most people; chiefly observed by hallucinations, delusions, confused thoughts
What may be the causes of psychosis?
Schizophrenia (most common)
Bipolar disorder
Neurodegenerative diseases
Severe depression
Severe stress
Sleep deprivation
Alcohol & drug abuse“Positive” symptoms of schizophrenia
Delusions (often paranoid)
Hallucinations (often “hearing voices”)
Thought disorder (e.g. rambling speech)
Abnormal and disorganised behaviour
Catatonia (immobility, purposeless movement)
“Negative “ symptoms of schizophrenia
Social withdrawal
Low emotional responses
Inability to experience pleasure
Reluctance to perform tasks
What are the cognitive deficits of schizophrenia?
Poor memore
Low attention span
In the dopamine theory of schizophrenia, “positive symptoms “ are due to
Mesolimbic pathway: Dopamine overactive
D2 receptors predominate
In the dopamine theory of schizophrenia, the “ negative” symptoms are due to?
Mesocortical pathway: Dopamine underactive
D1 receptors predominate
Antipsychotics can be classified into
“First generation” or “typical” antipsychotics
“Second generation” or “atypical” antipsychotics
What is the major problem with antipsychotics
Compliance
Antipsychotics overdose effects?
sedation if mild
cardiotoxicity and seizure risk if severe
Extrapyramidal effects (EPS) of antipsychotics
Acute dystonia
Tardive dyskinesias
Endocrine effects of antipsychotics
↑ prolactin; breast swelling, pain,
lactation (also affects males)
Other side effects of antipsychotics
Sedation (Histamine H1 receptors, mAChR, a1)
•Weight gain (H1, 5-HT, mAChR)
•Hypotension (a adrenoreceptors)
•Anticholinergic effects e.g. dry mouth, blurred vision (mAChR)
•Sexual dysfunction (all receptors)
What is acute dystonia
Involuntary movements, muscle twitching
- Can be ameliorated by antimuscarinics and 5-HT1A receptor antagonists
- Reversible upon cessation of treatment of antipsychotics
- Later development of Parkinsonian symptoms, and then akathisia
- Neuroleptic malignant syndrome: hyperthermia, confusion, tachycardia.
What is tardive dyskinesia?
Upregulation & sensitisation of D2 receptors
- Involuntary movements of face, trunk & limbs; potentially disabling. Affects 20-40% of patients.
- Develop after months to years of treatment, especially with first generation drugs.
- May get worse after treatment cessation- often irreversible
All antipsychotics have cautions with cardiac dysfunction & risk of sudden death . True or false
Cause?
True
Inhibition of some cardiac K+ channels: torsade de points
What is the most commonly used 1st gen antipsychotics drug
Chlorpromazine
Haloperidol
1st gen antipsychotics drug
Rarely prescribed for long-term use (high EPS) Usually for treatment of acute delirium (IV), also nausea.
Chlorpromazine side effect
Notable side effect of jaundice, lower EPS than many other 1st gen antipsychotics
Zuclopenthixol
1st gen antipsychotics drug
Non-selective D1 / D2 antagonists. Available as depot preparation
What is the 2nd gen antipsychotics drug ?highly recommended antipsychotics drug used for treatment resistant with antipsychotics
Clozapine
Quietiapine & Olanzapine
2nd gen antipsychotics drug
Most prescribed. Olanzapine more efficacious than quetiapine, but worse motor side effects.
What is the First “2nd generation” antipsychotic, although discovered early (1958)
- Often effective in otherwise treatment-resistant patients
- Now rarely prescribed; serious side effect of agranulocytosis; sudden death (often myocarditis)
- Lack of EPS = useful for Parkinson’s Disease psychosis
Clozapine
Which 2nd gen antipsychotics drug is available as depot preparation; medium EPS?
Risperidone
Which 2nd gen antipsychotics drug is partial agonist at D2; lower DAergic side effects
moderate efficacy, relatively well tolerated?
Aripripazole
What is the first line treatment for schizophrenia?
2nd generation antipsychotics - less adverse effect
What is the wind June treatment for schizophrenia?
1st generation antipsychotics, chiefly chlorpromazine and related compounds
