Psych Drugs- Antipsychotics

Question 1

MOA: Blocks post-synaptic dopamine (D2) receptors

Answer 1

Haloperidol, chlorpromazine

Question 2

Indication: These first-generation drugs are indicated for the treatment of the manifestations of several psychotic disorders including schizophrenia, acute psychosis, Tourette syndrome, and other severe behavioural states. Typically not used first line, as these have more EPSE’s.

Answer 2

Haloperidol/Chlorpromazine

Question 3

Mechanism of action: Partial agonist of D2 receptors, serotonin 5HT2A antagonist, weak 5HT1a partial agonist

Answer 3

Second generation atypical antipsychotic: Aripiprazole

Question 4

This first-generation antipsychotic drug has a strong sedative effect, making it beneficial in acute psychomotor agitation

Answer 4

Chlorpromazine

Question 5

Common indications:
1. Rapid tranquilisation in severe psychomotor agitation that is causing dangerous or violent behaviour, or to enable assessment
2. Schizophrenia, particularly when the metabolic side effects of 2nd gen (atypical) anti-psychotics are problematic
3. Bipolar disorder, particularly in acute mania or hypomania
4. Nausea and vomiting, particularly in the palliative care setting

Answer 5

First generation (typical) antipsychotics: Haloperidol/chlorpromethazine
NB: Typically not first line due to EPSE’s

Question 6

Important adverse effects: Movement abnormalities such as acute dystonic reactions (involuntary Parkinsonian movements or muscle spasms), akathisia (state of inner restlessness), and neuroleptic malignant syndrome (rare but life-threatening s/e characteristed by rigidity, confusion, autonomic dysregulation, and pyrexia).
Other ADE’s include drowsiness, hypotension, QT prolongation/arrythmias, ED, and symptoms arising from hyperprolactinaemia

Later stages of treatment: Tardive dyskinesia (pointless, repetitive, involuntary movements e.g. lip smacking)

Answer 6

First generation (typical) antipsychotics: Halperidol, Chlorpromazine
NB: Typically not first line due to EPSE’s

Question 7

Important drug interactions for Haloperidol or Chlormpromethazine?

Answer 7

Other drugs that prolong the QT interval such as Amiodarone or macrolide antibiotics

Question 8

First line choice of drug for rapid-acting tranquilisation for violent behaviour?

Answer 8

IM Haloperidol injection