Antipsychotics Flashcards
What are the + symptoms of schizophrenia and psychosis?
“Acting out”
- Delusions
- Agitation
- Hallucinations
- Disorganized thinking
+ symptoms are associated with…?
“Typical antipsychotics” and Mesolimbic
What are the - symptoms of schizophrenia and psychosis?
“Depressed mood”
- Apathy
- Social isolation
- Poor speech
- symptoms are associated with…?
“Atypical antipsychotics” and Mesocortical
What is the dopamine (DA) hypothesis?
DA hypothesis says that excess DA in causes schizophrenic and psychotic behaviors.
Homovanillic acid is a metabolite of DA. There is an increased amount of urinary homovanillic acid in psychotic/schizophrenic patients.
What kind of drugs induce psychotic behavior?
Drugs that ↑ DA (AMANTADINE) and drugs that inhibit the reuptake of DA (AMPHETAMINE)
Mesolimbic pathway responsible for?
- Arousal
- Memory
- Behavior
Nigrostriatal pathway responsible for?
- Modulation of EPS
Tuberoinfundibular pathway responsible for?
- Regulation of prolactin
Mesocortical pathway responsible for?
- Cognition
* Socialization
MOA of Typical antipsychotics?
D2 receptor antagonists; blocks D2»_space;> 5-HT2
Blockade of D2 in mesocortical pathway leads to…?
Worsens the - symptoms
Blockade of D2 in the nigrostriatal pathway leads to…?
EPS, Parkinsonism
Blockade of D2 in the tuberoinfundibular pathway leads to…?
Prolactin release (Ex: men might have gynecomastia; milk discharge even when not pregnant)
When to use typical antipsychotics?
- Schizophrenia (Haloperidol)
- Drug-induced psychosis
- Tourette’s (haloperidol, pimozide)
What are the typical antipsychotics?
- Chlorpromazine (low potency)
- Fluphenazine (high potency)
- Haloperidol (high potency)
- Thioridazine
- Loxapine
- Trifluoperazine
- Thiothixene
- Pimozide (Tourette’s)
High potency = very strong antagonist of the D2 receptor. Most D2 blockade.
What are the typical antipsychotic toxicities?
- M, H1, alpha1 blockade
- EPS (dystonia, pseudoparkinsonism) - Treat with anticholinergics
- Akathisia - treat with Propranolol
- Menstrual irregularities, prolactin release
- Tardive dyskinesia
- Neuroleptic malignant syndrome (NMS)
Blockade of Muscarinic (M) receptor cause…?
- Dry mouth
- Blurred vision
- Constipation
- Urinary retention (pt. has problem with urination)
Blockade of H1 receptor causes…?
Sedation
Blockade of alpha1 receptor causes…?
Orthostatic hypotension
Tardive Dyskinesia
IRREVERSIBLE
Happens months - yrs. later
Tongue protrusion, lip smacking, abnormal movements, “Rabbit syndrome”
Neuroleptic malignant syndrome (NMS)
Different from Serotonin syndrome b/c occurs WEEKS - MONTHS later. No GI effect.
- Muscle rigidity, loss of consciousness, tachycardia, high fever, ↑ creatine kinase (b/c of muscle injury due to prolonged contraction), diaphoresis
- Decreased reflexes
- Normal Pupils
Which drug is used to treat NMS?
Dantrolene = a muscle relaxant
How does Dantrolene (for NMS) work?
Binds to ryanodine receptors and prevents Ca2+ release from the sarcoplasm ⤑ inhibits muscle contractions
