Unit 5.4: Adverse Drug Reactions and Medication Errors

• Topic 01

  Types of Adverse Drug Reactions

  42 questions
• Topic 02

  Drug Interactions and Contraindications

  53 questions
• Topic 03

  Anaphylaxis Recognition and Emergency Management

  48 questions
• Topic 04

  Medication Error Reporting

  46 questions

A few questions from this unit, with the answer and a full explanation. The complete bank is available when you start practising.

1. A male patient of Nigerian descent with a documented penicillin allergy is admitted with a complicated urinary tract infection. Blood tests show haemoglobin 142 g/L and normal renal function. The microbiologist recommends nitrofurantoin as a culture-guided therapy. Before administering the first dose, a nurse reviews the patient's record and notices a previous hospital note mentioning 'possible G6PD deficiency, not formally tested'. What is the MOST appropriate nursing action?

   • A
     Withhold the nitrofurantoin and contact the prescriber for G6PD testing or an alternative, as it risks severe haemolytic anaemia in G6PD deficiency.
     Correct answer
   • B
     Contact the pharmacist and ask whether a reduced nitrofurantoin dose is safe in suspected G6PD deficiency
   • C
     Administer the first dose and check the haemoglobin daily; haemolysis usually takes several days to develop, allowing time for monitoring
   • D
     Proceed with nitrofurantoin because the UTI is a clinical urgency that outweighs the theoretical G6PD risk in this patient
   Explanation

   Nitrofurantoin can precipitate acute haemolytic anaemia in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency, an X-linked enzyme deficiency more prevalent in people of African, Mediterranean, Middle Eastern, and Asian descent, and more commonly symptomatic in males. Because G6PD deficiency has not been formally confirmed or excluded in this patient, and nitrofurantoin is a recognised trigger for severe haemolysis in G6PD deficiency, it should be withheld until the prescriber has reviewed the record, either confirming G6PD status or selecting an alternative antibiotic. A normal baseline haemoglobin does not rule out G6PD deficiency, as haemolysis is triggered by drug exposure rather than being present at baseline.

2. What is the primary reason intramuscular adrenaline is preferred over intravenous adrenaline for first-responding nurses?

   • A
     IV adrenaline is slower to act than IM in anaphylaxis because venous blood takes longer to reach the heart than muscle perfusion
   • B
     IV adrenaline has a significantly higher therapeutic dose requirement and is too expensive for routine emergency use
   • C
     IM adrenaline reaches the bloodstream faster than IV adrenaline because muscle tissue has a higher blood flow than venous blood
   • D
     IM adrenaline has a predictable safety profile; IV adrenaline risks fatal arrhythmia without specialist training and cardiac monitoring
     Correct answer
   Explanation

   IM adrenaline has a wide margin of safety when given at the standard dose into the anterolateral thigh: it is absorbed steadily, and significant cardiac adverse effects such as arrhythmia or a severe hypertensive spike are uncommon at this dose and route. IV adrenaline, by contrast, produces a much faster and less predictable rise in plasma concentration, and carries a real risk of causing dangerous arrhythmias or a hypertensive crisis if given too quickly or without titration.

   For this reason, IV adrenaline in anaphylaxis is reserved for experienced practitioners, such as anaesthetists or intensivists, working with continuous cardiac and blood pressure monitoring, typically in refractory cases. First-responding ward nurses are trained and expected to give IM adrenaline, which does not require this level of monitoring and has a well-established safety record in emergency use.

3. Who is eligible to submit a Yellow Card report?

   • A
     Only healthcare professionals who directly administered the drug causing the suspected ADR
   • B
     Only nurses who hold a nurse prescriber qualification
   • C
     Only registered pharmacists and pharmacy technicians
   • D
     Any healthcare professional, patient, or carer
     Correct answer
   Explanation

   The Yellow Card Scheme is open to anyone who suspects an adverse drug reaction: all healthcare professionals (nurses, doctors, pharmacists, dentists, allied health professionals), patients and carers, and members of the public.

   This broad eligibility, introduced in 2008 for patients/carers, was designed to capture the patient perspective on ADRs (particularly those that patients experience but may not report to their clinician). Healthcare professionals report via the Yellow Card website or app, while patients and carers can report via the same routes or via their GP/pharmacist.