Antipsychotic drugs Flashcards
What are the major EPS symptoms of antipsychotic drugs?
1) Dystonia (onset-minutes to hours)
2) Akathisia ( 7 days- weeks)
3) Parkinsonianism (1 week- months)
4) Tardive dyskinesia (months to years-can be irreversible)
Which antipsychotic should be used in cases that are refractory to other drugs?
Clozapine (Clozaril)
Which antipsychotic should be used in cases of acute psychosis and what are its major side effects?
Olanzapine (Zyprexa) => weight gain, metabolic syndrome, and seizures
-Risperidone (Risperdal) is also a good choice
After what dosage does Risperidone begin to show weight gain and EPS symptoms?
8mg
Which antipsychotic is better for patients with Parkinsons?
Quetiapine (seroquel) => Does not affect the D2 receptors that are affected in Parkinsons
What is the major side effect of quetiapine?
Somnolence and sedation
What antipsychotic can also be used to help with depression?
Aripiprazole (Abilify)
Which antipsychotic should be avoided in patients with dementia?
Aripiprazole (Abilify)
Which antipsychotic is weight neutral/doesn’t cause weight gain?
Ziprasidone (Geodon)
Which class of antipsychotics is associated with weight gain?
Atypicals
Which antipsychotic is the least expensive and most often used for acute psychosis?
Haloperidol
Which antipsychotic drug is associated with cardiac arrhythmias due to QT prolongation?
Ziprasidone (Geodon)
How do neuroleptics (antispychotics) cause hyperprolactinemia?
Neuroleptics block the tuberoinfundibular tract which causes increased prolactin leading to: gynecomastia, galactorrhea, and menstrual irregularities
How do neuroleptics (antipsychotics) cause EPS?
Neuroleptics block the nigrostriatal tract which leads to the EPS of: tremor, slurred speech, akathisia, dystonia, and tardive dyskinesia.
Which drugs treat EPS?
- Dystonia => benztropine (cogentin), benydryl
- Parkinsonism/Akinesia => Benztropine, Benadryl (anti-cholinergic agents)
- Akathisia => beta blockers (propranolol), benzodiazepines
What is neuroleptic malignant syndrome?
Often due to high potency antipsychotics:
- change in mental status
- autonomic changes (high fever, elevated BP, tachycardia)
- rigidity
- sweating
- elevated CPK
- leukocytosis
- metabolic acidosis
- If these symptoms are seen, stop the offending agent
How do high potency and low potency typical antipsychotics differ in side effects?
- High potency => more EPS (bind D2 more tightly)
- Low potency => more anticholinergic/cardiotoxic side effects (tend to block muscarinic receptors more)
What is the difference in the mechanism of action of typical vs atypical antipsychotics?
Typical => block D2
Atypical => less D2 blockade, more 5HT2a blockade
What are some high potency typical anti-psychotics?
Fluphenazine, Trifluoperizine, Thiothixene, Haloperidol, Pimozide
- medium-low sedation, high EPS, low anti-cholinergic side effects
What are some low potency typical anti-psychotics?
Chlorpromazine, Thioridazine
- medium-high sedation, low EPS, high anti-cholinergic/cardiac (QT prolongation) side effects
Why are EPS caused?
cholinergic/dopamine imbalance
- Decreased dopamine, increased Ach
What anti-cholinergic side effects are associated with typical anti-psychotics?
- Dry mouth, blurred vision, constipation, urinary retention, sedation, tachycardia, confusion, delirium, mydriasis, cycloplegia
What other side effects ( a part from anti-cholinergic and EPS) are caused by typical anti-psychotics?
Neutropenia Seizures Cardiac arrhythmias Hyperthermia Cataracts Priapism
What is the ranking of metabolic syndrome risk in the atypical anti-psychotics?
Clozapine (highest risk) > Olanzapine > Quetiapine, Risperidone > Ziprasidone, Aripiprazole (lowest risk)
What is the mechanism of action of Aripiprazole/Abilify?
Unique mechanism of action as a D2 partial agonist (at low doses only)
How is Aripiprazole different from other atypical antipsychotics in terms of side effect profile?
Low EPS, no/minimal QT prolongation or weight gain, low sedation
What is Quetiapine/Seroquel most commonly used as?
Anti-psychotic with sedation
What are the main side effects of Quetiapine/Seroquel?
- Transaminitis
- Orthostatic hypotension
Which atypical anti-psychotic functions more like a typical anti-psychotic?
Risperidone/Risperdal ( especially >6mg)
What atypical is most likely to induce hyperprolactinemia, weight gain, and sedation?
Risperidone/Risperdal
What atypical anti-psychotic must be taken with food as it increases absorption (nearly 100%)?
Ziprasidone/Geodon
What are the major side effects of Ziprasidone/Geodon?
Vomiting/Nausea
Which atypical antipsychotic has its blood levels reduced by smoking and causes transaminitis in a small minority of patients?
Olanzapine/Zyprexa
Which atypical is the only drug known to reduce suicide risk in patients with schizophrenia?
Clozapine
What are the major side effects of Clozapine/clozaril?
- Agranulocytosis => monitor weekly for first 6 months (weekly blood tests)
- Increased risk of seizures
- Myocarditis
- Associated with most sedation, weight gain, orthostasis, and transaminitis
- Metabolic syndrome
What atypical is least likely to cause EPS?
Clozapine
