MSRA MSRA Pharmacology and Prescribing 3

Question 1

A patient presents 4 hours after a suspected paracetamol overdose. What is the most important initial investigation?

Accepted Answer

Serum paracetamol level

Answer

The serum paracetamol level at 4 hours post-ingestion is plotted on the treatment nomogram to determine whether N-acetylcysteine (NAC) therapy is indicated.

Question 2

A patient with end-stage renal failure requires analgesia for severe pain. Which opioid is most appropriate?

Accepted Answer

Fentanyl

Answer

Fentanyl is the preferred opioid in renal failure as it has no active metabolites; morphine and codeine accumulate toxic metabolites (morphine-6-glucuronide and norcodeine) that cause prolonged sedation and respiratory depression.

Question 3

A patient on carbamazepine develops a skin rash. What is the most important immediate action?

Accepted Answer

Stop carbamazepine immediately

Answer

Carbamazepine can cause life-threatening cutaneous reactions including Stevens-Johnson syndrome and toxic epidermal necrolysis; any rash warrants immediate drug discontinuation.

Question 4

Which statement best describes first-order pharmacokinetics?

Accepted Answer

The rate of elimination is proportional to the drug concentration

Answer

In first-order kinetics, the rate of drug elimination is proportional to the plasma concentration, resulting in a constant half-life — the majority of drugs at therapeutic doses follow this pattern.

Question 5

A patient started on amiodarone requires long-term monitoring. Which combination of side effects should be routinely screened for?

Accepted Answer

Thyroid dysfunction, hepatotoxicity, pulmonary toxicity, and corneal microdeposits

Answer

Amiodarone contains iodine, has an extremely long half-life (~40–55 days), and affects multiple organ systems: thyroid (hypo/hyperthyroidism), liver, lungs (fibrosis), and cornea (microdeposits), all requiring regular monitoring.

MSRA Exam (Multi-Specialty Recruitment Assessment) Practice Test

MSRA Exam (Multi-Specialty Recruitment Assessment) Practice Test

MSRA MSRA Pharmacology and Prescribing 3