L5 Antipsychotics Flashcards
What are the 5 symptom domains of schizophrenia?
- pos
- neg
- anx/dep
- aggressive
- cognitive
What kind of symptoms are most distressing for an individual with schizophrenia?
Negative symptoms. In contrast, positive phases are characterised by lack of insight (self-awareness of abnormal behaviour)
Examples of positive symptoms of schizophrenia (4)
- Delusions, often paranoid
- Hallucinations eg. exhortatory voices
- Thought disorder including feeling that thoughts are controlled by an outside agency
- Abnormal behaviours eg. stereotypical or aggressive behaviour
What kind of symptoms are most disturbing to others, usually leading to first referral to a psychiatrist and detection of schizophrenia?
Positive symptoms, abnormal behaviours added
Examples of negative symptoms of schizophrenia (2)
- Withdrawal from social contacts
2. Flattening of emotional responses
As the disease progresses, which kind of symptoms generally dominates?
Negative symptoms, normal behaviours subtracted
Why is cognitive dysfunction an important symptom of schizophrenia?
Predicts level of social and vocational functioning and hence, treatment outcome, better than positive symptoms
- Persistent core feature of the disease, not iatrogenic
What are some evidences suggesting that schizophrenia might be a neurodevelopmental disorder?
- Onset in late adolescence/early adulthood is consistent with neurodevelopmental abnormality involving cortio-cortical pathways
- Evidence of enlarged ventricles, abnormalities in laminar organisation of cortical cells
Neurochemical theories (3)
Primarily theories of the positive symptoms
- Dopamine Theory
- 5-HT (Serotonin) Theory
- Glutamate Theory
What is the most important basis for pharmacotherapy of schizophrenia?
All antipsychotic drugs are D2 antagonists - the dopamine theory
What is the dopamine theory?
Amphetamine produces symptoms similar to acute schizophrenia
What are the dopamine pathways of the brain? (4)
- Nigrostriatal
- Mesolimbic
- Mesocorticol
- Tuberoinfundibular
What is the MOA for many of the newer antipsychotics?
5-HT2 antagnosim - the serotonin theory
What is the serotonin theory?
LSD, a 5-HT2 agonist, produces symptoms similar to acute schizophrenia
What is the glutamate theory?
Drugs that block the NMDA receptor channel eg. phencyclidine (PCP) and ketamine, produce symptoms similar to acute schizophrenia
Which typical antipsychotic has a better side effect profile? Chlorpromazine or Haloperidol
Haloperidol