antipsychotics

Question 1

what are typical antipsychotics?

Answer 1

known as ‘first-generation’ antipsychotics, these not only act as antagonists to D2 receptors but also on cholinergic, adrenergic and histaminergic receptors

Question 2

examples of typical antipsychotics?

Answer 2

Haloperidol, Chlorpromazine and flupentixol.

Question 3

s/e of typical antipsychotics?

Answer 3

Side effects can therefore be grouped according to receptor blockade:
Dopamine D2 Receptor Blockade
Histamine H1 Receptor Blockade
Alpha-1 Adrenergic Receptor Blockade
Muscarinic Receptor Blockade

Question 4

what are s/e of Dopamine D2 Receptor Blockade in typical?

Answer 4

Extrapyramidal Symptoms (EPS)
Hyperprolactinemia

Question 5

what are symptoms of EPS in typical?

Answer 5

Question 6

what are symptoms of hyperprolactinaemia in typical?

Answer 6

Question 7

features of H1 receptor blockade in typical?

Answer 7

Sedation: Drowsiness and sleepiness.

Question 8

features of A1 adrenergic receptor blockade in typical?

Answer 8

Orthostatic Hypotension: A sudden drop in blood pressure upon standing, leading to dizziness or fainting.

Question 9

features of muscarinic receptor blockade in typical?

Answer 9

Anticholinergic Effects:

Dry mouth.
Constipation.
Blurred vision.
Urinary retention.

Question 10

what are atypical antipsychotics?

Answer 10

known as ‘second-generation’ antipsychotics, these are D2, D3 and 5-HT2A antagonists, with less overspill into other receptors.

Question 11

how do atyipcials compare to typical?

Answer 11

as effective and more favourable side effect profile with reduced extrapyramidal effects, but increased metabolic side-effects.

Question 12

when are atypical antipsychotics used?

Answer 12

1st line for new-onset psychosis

Question 13

examples of atypical antipsychotics?

Answer 13

risperidone, quetiapine, olanzapine, aripiprazole and clozapine

Question 14

what are the blockades affected in atypical?

Answer 14

D2 Receptor Blockade:
5-HT2A Receptor Blockade:
Histamine H1 Receptor Blockade:
Alpha-1 Adrenergic Receptor Blockade:
Muscarinic Receptor Blockade:

Question 15

s/e of D2 blockade in atypical?

Answer 15

Question 16

s/e of serotonin/5-HT2A blockade in atypical?

Answer 16

Lower Risk of EPS: Atypicals have a reduced risk of causing EPS due to serotonin receptor blockade.

Question 17

s/e of H1 blockade in atypical?

Answer 17

Sedation: Although less common than with typicals, some atypicals can cause drowsiness.

Question 18

s/e of A1 adrenergic blockade in atypical?

Answer 18

Orthostatic Hypotension: Some atypicals may cause a drop in blood pressure upon standing.

Question 19

s/e of muscarinic blockade in atypical?

Answer 19

Anticholinergic Effects:

Generally less pronounced compared to typicals.
Mild dry mouth, constipation, or blurred vision.

Question 20

what are metabolic effects in atypical?

Answer 20

weight gain
dyslipidaemia + impaired glucose metabolism
elevated prolactin > menstrual irregularities + sexual dysfunction

Question 21

what other s/e in atypical?

Answer 21

low risk of seizures
QT prolongation
increased VTE and stroke risk in elderly

Question 22

when should weight be monitored in atypicals?

Answer 22

Weight should be measured at the start of therapy, then weekly for the first 6 weeks, then at 12 weeks, at 1 year, and then yearly.

Question 23

when should blood glucose be monitored in atypicals?

Answer 23

Fasting blood glucose, HbA1c, and blood lipid concentrations should be measured at baseline, at 12 weeks, at 1 year, and then yearly.

Question 24

when should prolactin be monitored in atypicals?

Answer 24

Prolactin concentrations should also be measured at baseline.

Question 25

when should ECG be done in atypicals?

Answer 25

Before initiating antipsychotic drugs, an ECG may be required, particularly if there are cardiovascular risk factors (e.g. high blood pressure), if there is a personal history of cardiovascular disease, or if the patient is being admitted as an inpatient.

Question 26

when should BP be checked in atypicals?

Answer 26

Blood pressure monitoring before starting therapy, at 12 weeks, at 1 year and then yearly during treatment and dose titration of antipsychotic drugs

Question 27

what is clozapine?

Answer 27

Clozapine is an atypical antipsychotic that is indicated if there is failure of treatment of 2 other antipsychotic medication, known as treatment-resistant schizophrenia.

Question 28

what does clozapine treat?

Answer 28

Treats both positive and negative symptoms, slightly more effective than other antipsychotics.

Question 29

s/e of clozapine?

Answer 29

agranulocytosis, neutropenia, reduced seizure threshold, myocarditis, slurred speech (due to hypersalivation), constipation

Question 30

what is the most common cause of mortality when related to clozapine use?

Answer 30

constipation

Question 31

how is clozapine montiored?

Answer 31

weekly FBC for the first 18 weeks of treatment then fortnightly for up to one year, and then monthly.

Blood lipids and weight should be measured at baseline, every 3 months for the first year, and then yearly.

Fasting blood glucose should be tested at baseline, after one months’ treatment, then every 4–6 months.

Question 32

what is neuroleptic malignant syndrome?

Answer 32

Neuroleptic Malignant Syndrome (NMS) is a rare, but potentially life-threatening, idiosyncratic reaction to antipsychotic medications, particularly those that block dopamine receptors. It typically occurs as a response to the introduction or an increase in the dosage of neuroleptic medications.

Question 33

features of neuroleptic malignant syndrome?

Answer 33

hyperthermia
fluctuating consciousness
autonomic dysregulation ie fluctuating BP, tachycardia + diaphoresis
rigidity

Question 34

what ix should be done in neuroleptic malignant syndrome?

Answer 34

Question 35

how do you manage neuroleptic malignant syndrome?

Answer 35

Discontinuation of Causative Agent

Aggressive cooling measures to address hyperthermia, including cooling blankets and IV fluids to prevent renal failure

benzodiazepines to manage agitation and muscle rigidity

dantrolene - skeletal muscle relaxant

vitals, fluid balance etc