DHA Clinical Pharmacy exam questions

6 worked Clinical Pharmacy practice questions

Original exam-style questions from the bank, spread across the blueprint domains. They are not real or recalled exam questions. Try each one, then open the answer for the rationale and reference. None of them appear in the free mock exam, so reading them will not spoil it.

1. Question 1 · Cardiovascular Pharmacotherapy

   An 80-year-old on digoxin 125 micrograms daily for AF rate control is started on amiodarone. What adjustment is recommended?

   1. AReduce the digoxin dose by about half
   2. BIncrease the digoxin dose by half
   3. CNo change is needed
   4. DStop amiodarone after loading
   Show answer and explanation

   Correct answer: A. Reduce the digoxin dose by about half

   Amiodarone inhibits P-glycoprotein and reduces digoxin clearance, roughly doubling digoxin concentrations, so the digoxin dose is reduced by about half with level monitoring. Leaving the dose unchanged risks digoxin toxicity, particularly in an older patient.

   Reference: Amiodarone Prescribing Information; Stockley's Drug Interactions, 12th ed.

2. Question 2 · Critical Care, Renal and Hepatic Considerations

   A patient on dialysis has potassium 7.1 mmol/L with peaked T waves and widened QRS complexes. What should be given first?

   1. AIV calcium gluconate
   2. BOral sodium polystyrene sulfonate
   3. CIV furosemide
   4. DOral sodium bicarbonate
   Show answer and explanation

   Correct answer: A. IV calcium gluconate

   IV calcium gluconate stabilises the myocardial membrane within minutes and is the first step when hyperkalaemia causes ECG changes. Insulin with glucose then shifts potassium into cells; resins act too slowly for an emergency.

   Reference: UK Kidney Association Clinical Practice Guideline: Treatment of Acute Hyperkalaemia in Adults 2023

3. Question 3 · Endocrine, Respiratory and Gastrointestinal Pharmacotherapy

   A patient's TSH has risen after she started calcium carbonate and ferrous sulfate taken together with her morning levothyroxine. What is the most appropriate advice?

   1. ATake levothyroxine at least 4 hours apart from calcium and iron
   2. BDouble the levothyroxine dose
   3. CStop the calcium and iron permanently
   4. DTake levothyroxine with breakfast and the minerals
   Show answer and explanation

   Correct answer: A. Take levothyroxine at least 4 hours apart from calcium and iron

   Calcium and iron bind levothyroxine in the gut and reduce its absorption, so separating them by at least 4 hours usually corrects the problem. Increasing the dose without separating the drugs leads to variable control.

   Reference: ATA Guidelines for the Treatment of Hypothyroidism 2014

4. Question 4 · Infectious Diseases and Antimicrobial Stewardship

   A 58-year-old has bacteraemia from a urinary source with ESBL-producing Klebsiella pneumoniae, susceptible to piperacillin/tazobactam and meropenem. What is the preferred definitive therapy?

   1. APiperacillin/tazobactam
   2. BMeropenem
   3. CCeftriaxone
   4. DAmoxicillin/clavulanate
   Show answer and explanation

   Correct answer: B. Meropenem

   A carbapenem is preferred for ESBL bloodstream infection because the MERINO trial showed higher 30-day mortality with piperacillin/tazobactam even when reported susceptible. Ceftriaxone is hydrolysed by ESBLs and is unreliable.

   Reference: IDSA Guidance on Treatment of Antimicrobial-Resistant Gram-Negative Infections 2024

5. Question 5 · Neurology, Psychiatry and Pain

   A woman stable on lithium for bipolar disorder develops coarse tremor, vomiting and confusion 2 weeks after a new antihypertensive was added. Her lithium level is 1.9 mmol/L. Which drug most likely caused this?

   1. AAmlodipine
   2. BDoxazosin
   3. CHydrochlorothiazide
   4. DAtenolol
   Show answer and explanation

   Correct answer: C. Hydrochlorothiazide

   Thiazide diuretics reduce renal lithium clearance by increasing proximal sodium and lithium reabsorption, raising lithium levels by around 25-40%. ACE inhibitors and NSAIDs also raise lithium, while amlodipine, doxazosin and atenolol have no clinically important effect on its clearance.

   Reference: Stockley's Drug Interactions, 12th ed.

6. Question 6 · Oncology, Haematology and Anticoagulation

   An 82-year-old woman with non-valvular AF weighs 58 kg and has a serum creatinine of 95 micromol/L. What apixaban dose is appropriate?

   1. A5 mg twice daily
   2. B2.5 mg once daily
   3. C10 mg twice daily
   4. D2.5 mg twice daily
   Show answer and explanation

   Correct answer: D. 2.5 mg twice daily

   Apixaban is reduced to 2.5 mg twice daily in AF when at least two of age 80 or over, weight 60 kg or less, or creatinine 133 micromol/L or more are present; she meets the age and weight criteria. Once-daily dosing is not a licensed regimen for apixaban.

   Reference: Apixaban Summary of Product Characteristics; EHRA Practical Guide on NOACs 2021