History Taking · Intermediate · Respiratory

Persistent Dry Cough

Practise this PLAB 2 history taking station on ACE Inhibitor-Induced Cough. 8-minute voice AI simulation with feedback on all 3 marking domains.

Clinical scenario

You are an FY2 doctor in general practice. Mr David Patterson, a 62-year-old man, has come to see you with a persistent dry cough that has developed over the past three months. He describes it as non-productive, worse at night and when lying down, and not associated with fever or sputum. Please take a focused history to establish the differential diagnosis and discuss initial management.

Background notes: PMH: Hypertension, Type 2 Diabetes, Hypercholesterolaemia, GORD (longstanding)

What this station tests

  • Identifying ACE inhibitor cough through drug history: recognising enalapril as the likely cause despite the two-year delay between initiation and symptom onset
  • Systematic exclusion of competing differentials: GORD (longstanding, stable on PPI), postnasal drip (no nasal symptoms), asthma (no wheeze or atopy), cardiac failure (no orthopnoea, good exercise tolerance)
  • Switching ACE inhibitor to ARB correctly: naming the alternative, explaining that it works similarly without causing cough, and emphasising the need for continued antihypertensive treatment
  • Avoiding premature diagnostic closure: arranging follow-up to confirm cough resolution and planning further investigation if it persists
  • Red flag screening for persistent cough: excluding malignancy (no haemoptysis, weight loss, or smoking history) and infection (no fever, no productive sputum)

How to use your 8 minutes

  • 0-1 min — Introduction: Introduce yourself, confirm identity, open question. 'What's brought you in today?'
  • 1-4 min — Systematic History: Presenting complaint detail (SOCRATES for pain, timeline, severity). Systems review. PMH, medications, allergies.
  • 4-6 min — Context and ICE: Social history (smoking, alcohol, occupation, living situation). Family history. Ideas, Concerns, Expectations.
  • 6-7 min — Summary and Plan: Summarise findings back to patient. Share differential/working diagnosis. Outline investigation and management plan.
  • 7-8 min — Closing: Safety netting with specific red flags. Arrange follow-up. Check for questions.

Consultation approach

The opening

Chronic cough stations test differential diagnosis through targeted history. The drug history is often the key to the diagnosis, yet many candidates leave it until late in the consultation. For any patient with a persistent dry cough, ACE inhibitor use should be one of the first things you check. Mr Patterson is 62, retired, with a three-month dry cough that is worse at night and when lying down. Open with: 'Tell me about this cough. When did it start and what is it like?' Let him describe it, then move systematically through the differential.

Core approach

The cough is dry, completely non-productive, persistent for three months, worse at night and lying down, not triggered by exercise, cold, or food. No sputum, no fever, no weight loss, no haemoptysis, no breathlessness. He can walk two miles without difficulty. These features are important for what they exclude: no red flags for malignancy, no productive features for infection, no wheeze for asthma, no exertional breathlessness for cardiac failure.

The drug history is the diagnostic key. Mr Patterson takes enalapril 10mg daily for hypertension. ACE inhibitors cause a dry cough in 10 to 20% of patients due to bradykinin accumulation in the airways. Crucially, the timing does not always match initiation: he has been on enalapril for two years, but ACE inhibitor cough can develop at any point, not just in the first weeks. His wife suggested it might be his blood pressure tablet, which is a useful clue that candidates should explore if mentioned.

Exclude the competing differentials through targeted questioning. GORD: he has longstanding GORD on omeprazole and gets heartburn 2 to 3 times weekly. Reflux-related cough is a possibility, but it typically responds to PPI optimisation, and his cough started months into stable omeprazole therapy. Postnasal drip: no nasal congestion, no rhinorrhoea, no sneezing, no sinus pain. Asthma: no wheeze, no atopy, no childhood asthma, not exercise-triggered. Cardiac failure: no orthopnoea (sleeps on one pillow), no PND, no ankle oedema, good exercise tolerance.

His other medications are metformin, atorvastatin, and omeprazole. No allergies. Non-smoker, occasional alcohol, good exercise tolerance. No occupational exposures.

Closing and safety netting

For ACE inhibitor cough, the management is straightforward but the explanation matters. 'Mr Patterson, I think your blood pressure tablet, enalapril, is the most likely cause of your cough. This is a well-known side effect that happens in about 1 in 5 people. Your wife may be right.' Explain the plan: stop enalapril today and switch to an ARB (losartan or valsartan), which works similarly but does not cause cough. The cough should resolve within 2 to 4 weeks of stopping.

Emphasise that he must not stop the blood pressure medication without a replacement: 'Your blood pressure still needs treating, especially with your diabetes and cholesterol. We are switching to a different type, not stopping.' Arrange a BP check in 2 weeks to confirm the new medication is working, and review the cough at 4 weeks.

Safety net: 'If the cough has not improved after 4 weeks on the new medication, come back and we will investigate further, including a chest X-ray.' This covers the possibility that the cough is not ACE inhibitor-related and avoids premature closure. Also: 'If you develop any blood in your sputum, unexplained weight loss, or worsening breathlessness, come back sooner.'

How examiners mark this station

Examiners will focus on the thoroughness and structure of your history taking for ace inhibitor-induced cough. Domain 1 (Data Gathering) carries the most weight: expect marks for systematic coverage of presenting complaint, red flags, PMH, medications, social and family history. Domain 2 (Clinical Management) requires a clear differential, appropriate investigations, and a safe management plan with safety netting. Domain 3 (Interpersonal Skills) is assessed throughout: genuine exploration of ICE, active listening, empathic responses, and clear communication without jargon.

Domain 1: Data Gathering, Technical and Assessment Skills (Primary focus)

Scores well: Early drug history identifying enalapril. Systematic exclusion of GORD, postnasal drip, asthma, and cardiac failure through targeted questions. Red flag screening for malignancy. Thorough medication review including adherence.

Costs marks: Not asking about medications until late. Not excluding GORD despite known history. Not screening for malignancy red flags. Missing the enalapril entirely.

Domain 2: Clinical Management Skills (Primary focus)

Scores well: Correct diagnosis of ACE inhibitor cough. Appropriate switch to ARB (naming losartan or valsartan). Emphasising continuous antihypertensive cover. Follow-up plan: BP check at 2 weeks, cough review at 4 weeks. Contingency if cough persists (chest X-ray). Appropriate red flag safety netting.

Costs marks: Not switching medication. Stopping enalapril without replacement. No follow-up plan. No contingency for persistent cough. Missing red flag safety netting.

Domain 3: Interpersonal Skills (Throughout)

Scores well: Acknowledging his wife's suggestion (she suspected the blood pressure tablet). Explaining why the timing does not exclude the diagnosis. Clear, reassuring explanation of the switch. Checking his understanding of why continued BP treatment matters.

Costs marks: Dismissing his wife's suggestion. Not explaining the mechanism. Medical jargon ('bradykinin accumulation'). Not checking understanding.

Common examiner feedback (and how to fix it)

Did not gather sufficient information to make an adequate assessment of the patient's condition

Fix: Use a consistent framework for every history. After covering the presenting complaint, systematically move through PMH, drug history, social history, family history, and ICE. Keep a mental checklist.

Did not identify the patient's problems and/or did not develop a management plan adequately

Fix: Reserve the final 2 minutes to summarise your findings, share your working diagnosis with the patient, and outline your investigation and management plan including safety netting.

Common mistakes in this station

  1. Not checking the drug history early enough. Many candidates take a full respiratory history, examine differentials, and only ask about medications at the end. For a persistent dry cough, ACE inhibitor use should be checked within the first 2 minutes. The diagnosis is in the drug history.
  2. Dismissing ACE inhibitor cough because the patient has been on enalapril for two years. ACE inhibitor cough can develop weeks, months, or even years after initiation. The timeline does not exclude it. Candidates who say 'he's been on it too long for that to be the cause' demonstrate a knowledge gap.
  3. Not emphasising the need to continue antihypertensive treatment. Mr Patterson has hypertension, diabetes, and hypercholesterolaemia. Stopping his blood pressure medication without replacement is unsafe. Candidates must explicitly state they are switching, not stopping.

Resitting PLAB 2?

If you have previously struggled with history taking stations, focus on building a consistent systematic framework that you apply to every case. Practise structuring your history into clear phases (presenting complaint, systems review, PMH, social, ICE) so that even under pressure, you cover all domains. Many resitters lose marks not on knowledge but on organisation and time management.

Example opening

Good morning/afternoon, my name is Dr [Name], I'm one of the doctors here today. Could I confirm your name and date of birth please? Thank you. So, what's brought you in to see me today?

Frequently asked questions

How do I approach the consultation in this ACE inhibitor-Induced cough station?

Chronic cough stations test differential diagnosis through targeted history. The drug history is often the key to the diagnosis, yet many candidates leave it until late in the consultation. For any patient with a persistent dry cough, ACE inhibitor use should be one of the first things you check.

What does a strong performance look like to the examiner in this station?

Strong performances show: Early drug history identifying enalapril. Systematic exclusion of GORD, postnasal drip, asthma, and cardiac failure through targeted questions. Weak performances: Not asking about medications until late. Not excluding GORD despite known history. Not screening for malignancy red flags.

What is the biggest pitfall in this ACE inhibitor-Induced cough station?

Not checking the drug history early enough. Many candidates take a full respiratory history, examine differentials, and only ask about medications at the end. For a persistent dry cough, ACE inhibitor use should be checked within the first 2 minutes.

How should I prepare for ACE inhibitor-Induced cough if I have never seen it in practice?

This station rewards process over personal experience. The skill being assessed: Systematic exclusion of competing differentials: GORD (longstanding, stable on PPI), postnasal drip (no nasal symptoms), asthma (no wheeze or atopy), cardiac failure (no orthopnoea, good exercise tolerance). Use the domain breakdown on this page to target your preparation, then practise the station aloud so your structure survives exam pressure.

Related cases