Psychiatric Pharmacology Flashcards
What are the mechanism of action of typical antipsychotics?
Dopamine D2 receptor antagonists, blocking dopaminergic transmission in the mesolimbic pathways.
What is the mechanism of action of atypical antipsychotics?
Act on a variety of receptors (D2, D3, D4, 5-HT).
What are the adverse effects of typical antipsychotics?
Extrapyramidal side effects
Hyperprolactinaemia (amenorrhoea)/galactorrhea),:
Impotence, galactorrhoea, headaches, hypopituitarism, visual field defects)
What are the examples of typical (first generation) anti psychotics?
Haloperidol
Chlopromazine
What are the side effects of atypical antipsychotics?
Metabolic
Extra pyramidal and hyperprolactinaemia side effects are less common.
What are the extrapyramidal side effects?
Parkinsonism
Acute dystocia
Akathisia
Tardive dyskinesia
What are the other side effects of antipsychotics?
C- dry mouth, blurred vision, urinary retention, constipation
Sedation, weight gain. Raised prolactin Impaired glucose tolerance Neurlopectic malignant syndrome Reduced seizure threshold (greater with atypical) Prolonged QT interval (haloperidol)
What are the specific warnings when antipsychotics are used in elderly patients?
Increased risk of stroke
Increased risk of VTE.
What is meant by Parkinsonism?
Any condition which causes a combination of the movement abnormalities seen in Parkinson’s disease- tremor, slow movement, impaired speech or muscle stiffness.
What is meant by acute dystocia?
Sustained muscle contraction
Can be managed with procyclidine
What is akathisia?
Severe restlessness
What is tardive dysknesia?
Face and/or body make sudden, jerky or slow wasting movements which a person cannot control.
What drug is particularly associated with prolonged QT interval?
Haloperidol
What is neuroleptic malignant syndrome?
Rare but potentially life threatening reaction to the use of almost any of a group of anti psychotic drugs or major tranquillisers (neuroleptic). It affects the nervous system and causes symptoms like a high fever and muscle stiffness.
Why is it anti psychotics cause hyperprolactinaemia?
Anti psychotics are dopamine antagonists
Dopamine is a prolactin antagonist
What are the metabolic side effects of antipsychotics?
Dysgylcaemia
Dyslipidaemia
Diabetes mellitus
What is the timeline like for alcohol withdrawal?
Symptoms start at 6-12 hours: tremor, sweating, tachycardia, anxiety
Peak incidence of seizure is at 36 hours
Peak incidence of delirium tremens is at 48-72 hours
What are the signs someone is in delirium tremens?
Coarse tremor Confusion Delusions Auditory and visual hallucinations Fever Tachycardia
What is the management of alcohol withdrawal?
Benzodiazepines- chlordiazepoxide
(Lorazepam maybe favoured in patients with hepatic failure)
Carbamazepine also effective in treatment of alcohol withdrawal