Psych Flashcards
(196 cards)
drugs that increase dopamine activity
amphetamines
methylphenidate
cocaine
cause/worsen psychosis and tourettes
measure of clinical potency of antipsychotics
ability to block dopamine D2 receptors
relieve positive symptoms
potency is directly related to risk of extrapyramidal symptoms
effect of 5HT2 blockade
relieve positive symptoms
perhaps some relief of negative symptoms
effect of muscarinic blockade w/ antipsychotics
confusion, memory impairment, protection against extrapyramidal side effects by blocking increase in DA turnover in basal ganglia
characteristics of atypical antipsychotics
Low D2 affinity (low potency)
High 5HT2 affinity
reduced risk of EPS
effective for negative symptoms
effect of a1 blockade
autonomic side effects: orthostatic hypotension, tachycardia
characteristics of typical antipsychotics
D2 blockers
produce EPS, urticaria/dermatitis
elevate PRL
effective for positive symptoms
phenothiazine with piperazine side chain
higher potency and risk of EPS
fluphenazine and perphenazine
phenothiazine with aliphatic side chain
low potency and risk of EPS
Chlorpromazine
antimuscarinic effect
causes orthostatic hypotension and sedation, increased risk of seizures, impairs glucose tolerance, decreases insulin resistance, jaundice, urticaria/dermatitis, associated with NM syndrome
phenothiazine with piperidine side chain
low potency and risk of EPS
Thiothixine
antimuscarinic effect
causes hypotension and sedation
butyrophenones
haloperidol
high potency
associated with NM syndrome
atypical antipsychotics
clozapine olanzapine quetiapine ziprasidone ripiprazole
risperidone MOA
low dose- D2/5HT2 blockade
*approved for use in children and teens
aripiprazole MOA
D2 partial agonist
5HT2A antagonist
5HT1 partial agonist
lower incidence of side effects
asenapine MOA
D1, D2, 5HT1, 5HT2, a, H1 blockade
low affinity for muscarinic receptors
neuroleptic syndrome
behavioral effects produced by antipsychotics
suppression of spontaneous movements and complex behaviors, reduced initiative and interest in environment, decreased emotion (flat affect), psychotic symptoms disappear over time
effect of D2 blockade on limbic system
reduction of psychosis and positive symptoms
long term therapy leads to increased synthesis, release, and neuronal activity of dopamine to overcome blockade
antimuscarinics have no effect on antipsychotic-induced increases in DA turnover
effect of D2 blockade on basal ganglia
causes EPS
long term therapy leads to increased synthesis, release, and neuronal activity of dopamine to overcome blockade
anticholinergics block antipsychotic-induced increases in DA turnover (block EPS symptoms)
EPS
early in therapy:
1) acute dystonia- stiff neck, oculogyric crisis, distorted facial expression
2) akathesia- restlessness, especially in the legs
3) parkinsonian syndrome- akinesia, rigidity, tremor, mask facies
4) neuroleptic malignant syndrome
delayed onset:
5) perioral tremor- rabbit syndrome
6) tardive dyskinesia- choreiform movements of face, eyelids, mouth, tongue
treatment of acute dystonia
anticholinergic (antiparkinsonian) agent such as benztropine
treatment of akathesia
decrease dose
add antiparkinsonian (anticholinergic) agent
anti-anxiety agent
propanolol
treatment of parkinsonian syndrome
anticholinergic parkinsonian agents
amantadine
neuroleptic malignant syndrome
develops in 1-3 days
hyperthermia (fever)- D2 blockade in hypothalamus
autonomic dysfunction- D2 blockade on SNS
Muscle rigidity and extrapyramidal tremor- D2 blockade in SN causes increased Ca release from SR (elevated CK, myoglobinemia)
treatment of neuroleptic malignant syndrome
stop antipsychotic
dantrolene for fever/skeletal muscle relaxation
dopamine agonist- bromocriptine competes for dopamine receptors
Lorazepam- reduce psychosis