Antipsychotics - Bloom Flashcards
Give 4 major behavioral features of psychosis
- Derangement of personality
- Loss of contact with reality
- Delusions
- Hallucinations
Give 3 possible core positive symptoms of schizophrenia
Give 5 negative symptoms
Positive
- Delusions
- Hallucinations
- Disorganized speech
Negative
- Blunted affect
- Lack of spontaneity
- Poor abstract thinking
- Poverty of thought
- Social withdrawal
What is the dopamine hypothesis?
Schizophrenia is the results of hyperactivity of dopaminergic neurons or their receptors, particularly those with terminals in the limbic areas of the brain
Evidence: all effective antipsychotics interact with dopaminergic systems
Mesolimbic tract
- Origin?
- Function?
- Result of dopamine hyperactivity?
- A10
- Arousal, memory, stimulus processing, locomotor activity, motivational behavior
- Dopamine hyperactivity results in positive schizophrenic symptoms
Mesocortical tract
- Origin?
- Function?
- Result of diminished dopaminergic activity?
- A10
- Cognition, communication, social activity
- Diminished dopaminergic activity leads to negative schizophrenic symptoms
Nigrostriatal pathway
- Origin?
- Course?
- Does dopamine blockade increase or decrease extrapyramidal symptoms (EPS)?
- What happens if 5-HT_2alpha is blockaded here?
- A9
- Substantia nigra to basal ganglia
- Increased EPS
- Decreased EPS, parkinsonism (possibly)
What is the effect of dopamine blockade in the tuberoinfundibular tract?
Increased prolactin release
Gs or Gi?
- D1
- D2
- D3
- D4
- D5
- G2
- Gi
- Gi
- Gi
- Gs
What trend among the neuroleptic drugs supports the dopamine hypothesis of schizophrenia?
Increased potency among these drugs is linearly related to affinity for D2 receptors.
What is the major mechanism difference between typical antipsychotics and newer atypical antipsychotics?
Newer atypicals also block 5-HT2 receptors (sometimes with potency greater than that of dopamine receptors)
Typical antipsychotics… name:
- (1) with an aliphatic side chain
- (2) with a piperazine side chain
- (1) with a piperidine side chain
- (1) thioxanthene
- (1) butyrophenone
- chlorpromazine
- fuluphenazine, trifluoperazine
- thioridazine
- thiothixene
- haloperidol
Name (3) atypical antipsychotics
- risperidone
- clozapine
- olanzepine
Are typical antipsychotic agents better at treating positive symptoms or negative symptoms?
Positive
Describe the major features of the extrapyramidal effects of antipsychotic drugs
Among these reactions, which presents the earliest? The latest?
- Dystonias
- Parkinsonism (moreso with typical antipsychotics)
- Akathisia (restlessness, difficulty holding still)
- Tardive dyskinesia (more frequent with typicals)
Acute dystonia develops first (1-5 days), followed by parkinsonism (5-30 days) and akathisia (5-60 days).
Tardive dyskinesia develops last, often over a period of months to years
Which typical antipsychotic may produce severe cardiac side effects?
thioridazine
Which side effect is more common with atypical antipsychotics than typicals? Which one in particular?
Weight gain
Olanzapine in particular
Which class of typical antipsychotic is particularly prone to lowering seizure threshold?
phenothiazines
What is a potentially lethal hypodopaminergic side effect of antipsychotic drugs?
Describe its symptoms
How do you treat it?
Neuroleptic Malignant Syndrome
Sx: hyperthermia, parkinson-like symptoms, mutism, death
Rx: cooling and hydration, bromocriptine (dopamine agonist), and dantrolene (muscle relaxant that abolishes excitation-contraction coupling in muscles, reducing hyperthermia)