Antipsychotics Flashcards
What are some other names for antipsychotics?
neuroleptics or major tranquilisers
What are antipsychotics typically used for?
- psychosis, including schizophrenia,
- and also in delirium
( quetiapine may be used for anxiety)
(bipolar, OCD, tourettes, huntingtons)
How are antipsychotics usually grouped?
typical antipsychotics (first generation) (aka FGA) and
atypical antipsychotics (second generation) (aka SGA).
Name 4 FGA?
First generation anti-psychotics e.g: (try fly high) - trifluoperazine - fluphenazine (depot (long acting) injection), - haloperidol,
(cheating thieves low)
- chlorpromazine,
- thioridazine
- clopenthixol
Name 7 SGA?
Atypical antipsychotics e.g:
- clozapine,
- risperidone,
- sertindole,
- aripiprazole,
- zotepine,
- olanzapine,
- quetiapine
It is said antipsychotic have what 4 important qualities?
- Sedation
- Anticholinergic activity
- Extrapyramidal activity
- Hypotensive effects
The drugs vary in how much they affect these areas. SGA/atypical are better at combating negative symptoms.
What is the pharmacologic mechanism shared by all antipsychotics?
D2 receptor blockage is the only pharmacological property shared by all antipsychotic drugs.
many also have effects on acetylcholine, noradrenaline, histamine and serotonin pathways leading to wide ranging side-effects.
What are the main dopamine pathways and what symptoms are they responsible for / do they control?
(antipsychotics are D2 antagonists)
[a]. Mesolimbic pathway: HIGH dopamine gives POSITIVE symptoms – delusions, hallucinations, disorganized speech/thinking and disorganized or catatonic behaviour
[b]. Mesocortical pathway: LOW dopamine gives NEGATIVE symptoms – Alogia, affective flattening, avolition etc.
[c]. Nigrostriatal pathway: Controls motor movement (blockade gives motor symptoms)
[D]. Tuberoinfundibular pathway: releases dopamine to reduce prolactin secretion.
(also in the CTZ)
What clinical implications does partial agonist on D2 receptors have?
Improved negative and positive symptoms, EPSE, prolactin changes.
What clinical implications does partial agonist on 5HT-1A receptors have?
Improved negative symptoms
What clinical implications does antagonist on 5HT-2A receptors have?
Sexual dysfunction; reduced EPSE and improved negative symptoms.
What clinical implications does antagonist on alpha-ADR-1 receptors have?
Postural hypotension, dizziness, reflex tachycardia
What clinical implications does antagonist on H1 receptors have?
Sedation, increased appetite, weight change, hypotension
What clinical implications does antagonist on M1 receptors have?
Minimal impact on blurred vision, dry mouth, constipation, urinary retention, sinus tachycardia
General differences between FGAs and SGAs?
FGAs:
- predominantly D2 action
- more EPSE
- prolactin elevation
- muscarinic cholinergic blocking
- less effect on negative symptoms
SGAs:
- lower D2 affinity
- high serotonin/dopamine binding ratio
- reduced EPSE
- more metabolic syndrome effects