Anti-psychotics Flashcards
Typical anti-psychotic mechanism?
block dopamine D2 receptors
Atypical anti-psychotic mechanism?
block both dopamine D2 and serotonin 2A receptors
What are the benefits of atypical vs typical?
atypicals may be more effective at treating neg symptoms
atypicals have favorable side effect profile (less EPS, tar dive dyskinesia or neuroleptic malignant syndrome), but greater metabolic syndrome/weight gain
atypicals often more expensive
What is the difference in side effects between low and high potency typicals?
Low potency requires higher dose–>higher incidence of anticholinergic and antihistaminic side effects (sedation, orthostatic); also more likely to cause seizures (lower seizure thresholds)
Low potency have more lethality in overdose due to QT prolongation
High potency have higher risk for extrapyramidal and tardive dyskinesia
Chlorpromazine (Thorazine) and Thioridazine (Mellaril) are low/mid/high potency typicals?
low
Chlorpromazine (Thorazine) specific side effects?
orthostatic hypotension, blueish skin discoloration, photosensitivity
Chlorpromazine (Thorazine) can also be used to treat…
nausea and vomiting, intractable hiccups
Thioridazine (Mellaril) specific side effects?
retinitis pigmentosa
Loxapine (Loxitane), thiothixene (Navane), Trifluoperazine (Stelazine) and Perphenazine (Trilafon) are low/mid/high potency typicals?
mid
Loxapine (Loxitane) specific side effects?
higher risk of seizure
*metabolite is an antidepressant amoxapine
Thiothixene (Navane) specific side effects?
ocular pigment changes
Trifluoperazine (Stelazine) can also help to…
reduce anxiety
Haloperidol (Haldol), Fluphenazine (Prolixin), Pimozide (Orap) are low/mid/high potency typicals?
high
What are the high-potency neuroleptics best used for?
as IM injections to treat acute agitation or psychosis
Haloperidol and fluphenazine are available as long acting IM forms known as:
deconate
What 4 dopamine pathways are affected by antipsychotics?
mesolimbic, mesocortical, nigrostriatum, tuberoinfundicular
Effect on the mesolimbic pathway by antipsychotics?
- positive symp of SCZ treated
Effect on the mesocortical pathway by antipsychotics?
- negative symp of SCZ treated
Effect on the nigrostriatal pathway by antipsychotics?
- EPS: parkinsonism, akathisia, dystonia (torticollis, tongue, oculogyric crisis, life-threatening if involves airway or diaphragm)
Effect on the tuberoinfundibular pathway by antipsychotics?
- hyperprolactinemia (dec libido, galactorrhea, gynecomastia, impotence, amenorrhea, osteoporosis)
When is the risk of tardive dyskinesia the greatest for a patient on neuroleptics?
> 6 months
- often older women
- 50% will spontaneously remit, but some cases are permanent
What medical emergency does one worry about with antipsychotics?
Neuroleptic malignant syndrome (especially young males early in treatment)
- FALTERED: Fever, Autonomic instability (tachy, labile HTN, diaphoresis), Leukocytosis, Tremor, Elevated creatine phosphokinase, Rigidity (lead-pipe), Excessive sweating (diaphoresis), Delirium
- 20% mortality rate
How does one treat EPS?
- anticholinergic: benztropine (Cogentin)
- antihistaminergic: diphenhydramine (Benadryl)
- antiparkinsonian: amantadine (Symmetrel)
Atypical antipsychotics are used to treat SCZ as well as…
acute mania, bipolar disorder, adjunctive to unipolar depression
sometimes for personality disorders and certain psychiatric disorders in childhood
Which atypical is least likely to cause tardive dyskinesia?
Clozapine (Clozaril)
Which atypical is the only one shown to be more efficacious?
Clozapine (Clozaril)
Which atypical has more anticholinergic side effects than other atypicals or high-potency typicals?
Clozapine (Clozaril)
Clozapine (Clozaril) specific side effects?
- associated with tachycardia and hypersalivation
- myocarditis
- 1-2% incidence of agranulocytosis (must have routine WBC counts weekly for first 6 mon must stop if absolute neutrophil count drops before 1500/uL)
- 2-5% incidence of seizures
Which atypical is the only antipsychotics shown to dec risk of suicide?
Clonzapine (Clozaril)
Which atypical has a long-acting injectable known as Consta?
Risperidone (Riserdal)
Risperidone (Risperdal) specific side effects?
- Hyperprolactinemia
- Orthostatic hypotension
- Reflex tachycardia
Quetiapine (Seroquel) specific side effects?
sedation and orthostatic hypotension
Olanzapine (Zyprexa) specific side effects?
Weight gain
Which two atypicals are less likely to cause weight gain?
Ziprasidone (Geodon) and Aripiprazole (Abilify)
Aripiprazole (Abilify) has what unique mechanism?
partial D2 agonism
Aripiprazole (Abilify) specific side effects?
can be more activating (akathisia) and less sedating
What atypicals have approval for treatment of mania?
Quetiapine (Seroquel), olanzapine (Zyprexa), aripiprazole (Abilify), risperidone (Risperdal), ziprasidone (Geodon)
What atypical has a long acting injectable form known as Sustenna?
Paliperidone (Invega)
- metabolite of risperidone
List the side effects of atypical antipsychotics
- Metabolic syndrome!
- weight gain!
- hyperlipidemia
- hyperglycemia
- some anti-HAM effects
- liver dysfunction
- QT prolongation
List atypicals
Clozapine (Clozaril), Risperidone (Risperdal), Quetiapine (Seroquel), Olanzapine (Zyprexa), Ziprasidone (Geodon), Aripiprazole (Abilify), Paliperidone (Invega), Asenapine (Saphris), Iloperidone (Fanapt)
