Cough (Adult)

Cough is one of the most common presenting symptoms in general practice and hospital medicine. It can be benign and self-limiting (e.g. viral upper respiratory tract infection), or the first sign of serious pathology such as lung cancer, tuberculosis, or heart failure. Understanding the time course, associated features, and risk factors is key to safe clinical practice.

🧠 Initial Clinical Approach

• ⏳ Duration:
  • Acute (<3 weeks): usually infection or acute irritant.
  • Subacute (3–8 weeks): post-infectious, pertussis, early TB.
  • Chronic (>8 weeks): asthma, COPD, reflux, cancer, ILD, ACEi.
• 📋 Character of cough: Dry vs productive; nocturnal; post-prandial; haemoptysis.
• 🌡️ Associated features: Fever, weight loss, wheeze, orthopnoea, heartburn.
• 🧑‍⚕️ History: Smoking, occupational exposures, TB risk, medications (esp. ACEi).
• 🫁 Examination: Chest auscultation (wheeze, crackles), signs of consolidation, heart failure, clubbing, lymphadenopathy.
• 📊 Red flags: Haemoptysis, weight loss, persistent symptoms, smoker, abnormal CXR.

🗣️ Discussion Points for Students

• Not every cough needs antibiotics — when is it safe to watch and wait?
• How do you distinguish postnasal drip from asthma in a young patient with a chronic cough?
• In an elderly smoker with cough and weight loss, why is early imaging crucial?
• What simple bedside observations (e.g. oxygen saturation, respiratory rate) guide urgency of investigations?
• How do public health considerations differ for TB or pertussis compared with COPD or reflux cough?

⚡ Causes of Cough: Clinical Features, Diagnostics, and Management

• 🤧 Upper Respiratory Tract Infection (Common Cold)
  • 📋 Clinical: Acute cough, rhinorrhoea, nasal congestion, sore throat, low-grade fever, malaise.
  • 🔎 Diagnostics: Clinical diagnosis; no tests needed.
  • 💊 Treatment: Supportive (hydration, rest, paracetamol, decongestants). Avoid antibiotics.
• 🌬️ Acute Bronchitis
  • 📋 Clinical: Cough (± productive), often post-viral, may have wheeze or chest discomfort.
  • 🔎 Diagnostics: Clinical; CXR if pneumonia suspected or elderly/high-risk.
  • 💊 Treatment: Supportive; bronchodilators if wheezy. Antibiotics rarely needed.
• 🫁 Asthma
  • 📋 Clinical: Episodic cough/wheeze, nocturnal or early AM, chest tightness, allergen/cold triggers.
  • 🔎 Diagnostics: Spirometry with reversibility, peak flow variability, bronchoprovocation, allergy testing.
  • 💊 Treatment: Stepwise inhaler therapy (SABA ➝ ICS ➝ LABA), allergen avoidance, action plan.
• 🍽️ Gastro-oesophageal Reflux (GERD)
  • 📋 Clinical: Chronic cough, worse post-prandially or lying flat, with heartburn or regurgitation.
  • 🔎 Diagnostics: pH monitoring, manometry, OGD if alarm features (dysphagia, weight loss, bleeding).
  • 💊 Treatment: Lifestyle (weight loss, bedhead elevation, avoid trigger foods). PPI/H2 blockers.
• 🚬 Chronic Obstructive Pulmonary Disease (COPD)
  • 📋 Clinical: Chronic productive cough, exertional breathlessness, wheeze. Smoking history common.
  • 🔎 Diagnostics: Spirometry (irreversible obstruction), CXR/CT, ABG in advanced disease.
  • 💊 Treatment: Smoking cessation 🚭, bronchodilators ± ICS, pulmonary rehab, O₂ if hypoxic.
• 🦠 Pneumonia
  • 📋 Clinical: Acute cough ± sputum, fever, chills, pleuritic chest pain, tachypnoea.
  • 🔎 Diagnostics: CXR (consolidation), sputum + blood cultures if sepsis suspected.
  • 💊 Treatment: Empirical antibiotics, oxygen/fluids as needed. Admit if CURB-65 ≥2.
• 🌊 Postnasal Drip (Upper Airway Cough Syndrome)
  • 📋 Clinical: Chronic cough, throat clearing, “mucus in throat”, worse supine.
  • 🔎 Diagnostics: Clinical; sinus imaging if chronic sinusitis suspected.
  • 💊 Treatment: Antihistamines, intranasal steroids, saline irrigation, treat rhinitis/sinusitis.
• ❤️ Heart Failure
  • 📋 Clinical: Chronic cough, orthopnoea, PND, frothy pink sputum in pulmonary oedema, ankle swelling.
  • 🔎 Diagnostics: Echo, BNP, CXR (cardiomegaly, pulmonary congestion).
  • 💊 Treatment: Diuretics, ACEi/ARB, beta-blockers, fluid/salt restriction.
• 🧨 Lung Cancer
  • 📋 Clinical: Persistent cough, haemoptysis, weight loss, hoarseness, recurrent chest infections.
  • 🔎 Diagnostics: CXR ➝ CT ➝ bronchoscopy/biopsy.
  • 💊 Treatment: Surgery (if operable), chemotherapy, radiotherapy, targeted therapy depending on stage/type.
• 🌫️ Interstitial Lung Disease (ILD)
  • 📋 Clinical: Chronic dry cough, progressive breathlessness, crackles, clubbing, occupational exposures.
  • 🔎 Diagnostics: HRCT (fibrosis/ground glass), PFTs, ± lung biopsy.
  • 💊 Treatment: Remove cause, immunosuppressants, antifibrotics, O₂, transplant if severe.
• 💊 ACE Inhibitor-Induced Cough
  • 📋 Clinical: Dry persistent cough, onset weeks after ACEi initiation.
  • 🔎 Diagnostics: Clinical; exclude other causes.
  • 💊 Treatment: Stop ACEi ➝ switch to ARB.
• 🦠 Tuberculosis
  • 📋 Clinical: Chronic cough, haemoptysis, weight loss, night sweats, fever.
  • 🔎 Diagnostics: CXR, sputum AFB smear/culture, NAAT.
  • 💊 Treatment: Prolonged multi-drug therapy (Rifampicin, Isoniazid, Pyrazinamide, Ethambutol).
• 🤒 Pertussis (Whooping Cough)
  • 📋 Clinical: Paroxysmal cough, inspiratory “whoop”, post-tussive vomiting; prolonged in adults.
  • 🔎 Diagnostics: PCR or serology; clinical suspicion in outbreaks.
  • 💊 Treatment: Macrolide antibiotics, public health notification, prophylaxis for contacts.
• 🌪️ Bronchiectasis
  • 📋 Clinical: Chronic productive cough, large volumes of purulent sputum, recurrent infections, clubbing.
  • 🔎 Diagnostics: HRCT (airway dilatation), sputum cultures.
  • 💊 Treatment: Chest physiotherapy, mucolytics, antibiotics, vaccinations.
• 🧠 Psychogenic / Habit Cough
  • 📋 Clinical: Chronic cough, absent during sleep, often stress-related. More common in children/teens.
  • 🔎 Diagnostics: Diagnosis of exclusion.
  • 💊 Treatment: Reassurance, behavioural therapy; avoid unnecessary medications.

🚩 Red Flags (Must Not Miss)

• Persistent cough >8 weeks
• Haemoptysis
• Unintentional weight loss
• Night sweats or fever
• History of smoking or occupational exposure
• Clubbing or focal chest signs

📊 Summary Table: Causes of Cough

🚩 Red Flags

• Haemoptysis
• Unexplained weight loss
• Night sweats/fever
• Cough >8 weeks
• Smoker or asbestos exposure
• Focal chest signs, clubbing

🧾 Clinical Case Examples

Case 1 – Acute viral cough 🤧 A 23-year-old student presents with a 5-day history of cough, sore throat, rhinorrhoea, and low-grade fever. Examination normal, sats 98%, chest clear. 👉 Likely diagnosis: Viral URTI. 👉 Management: Reassure, fluids, rest, paracetamol. No antibiotics needed.

Case 2 – Community-acquired pneumonia 🦠 A 68-year-old man with COPD has acute cough with purulent sputum, fever, and pleuritic chest pain. On exam: tachypnoea, crackles in right lower zone, sats 90%. CURB-65 = 3. 👉 Likely diagnosis: Pneumonia. 👉 Management: Admit, O₂, IV fluids, empirical antibiotics (e.g. IV co-amoxiclav + clarithromycin).

Case 3 – Asthma 🌬️ A 17-year-old girl has a 3-month history of nocturnal cough and wheeze, worse with cold weather. Peak flow shows diurnal variability. 👉 Likely diagnosis: Asthma. 👉 Management: Inhaled SABA as needed + regular low-dose ICS; asthma action plan.

Case 4 – GERD-related cough 🍽️ A 45-year-old man complains of a persistent dry cough, worse after meals and when lying flat. He has frequent heartburn. CXR is normal. 👉 Likely diagnosis: Reflux-related cough. 👉 Management: Lifestyle (weight loss, head-up sleeping, avoid late meals), trial of PPI.

Case 5 – Lung cancer 🚨 A 70-year-old smoker presents with a 3-month cough, haemoptysis, and 6 kg weight loss. Exam: clubbing and left supraclavicular lymph node. 👉 Likely diagnosis: Bronchogenic carcinoma. 👉 Management: Urgent 2-week wait CXR and CT chest; respiratory referral for bronchoscopy and biopsy.

Case 6 – Heart failure ❤️ A 76-year-old woman reports chronic cough, frothy sputum, orthopnoea, and swollen ankles. Exam: bilateral basal crackles, raised JVP, pitting oedema. 👉 Likely diagnosis: Congestive heart failure. 👉 Management: Loop diuretic for symptom relief, ACE inhibitor, beta-blocker, fluid restriction; cardiology follow-up.

Case 7 – Tuberculosis 🧪 A 32-year-old man recently arrived from India presents with a 6-week cough, night sweats, fever, and haemoptysis. Exam: cachexia, crackles in upper zones. 👉 Likely diagnosis: Pulmonary TB. 👉 Management: Sputum AFB smear and culture, CXR; notify public health; start RIPE therapy if confirmed.

Case 8 – Pertussis 🤒 A 9-year-old child has a 3-week paroxysmal cough with inspiratory “whoop” and post-tussive vomiting. Several classmates have similar symptoms. 👉 Likely diagnosis: Pertussis. 👉 Management: Macrolide antibiotic, notify public health, prophylaxis for household contacts.

Case 9 – ACE inhibitor cough 💊 A 60-year-old hypertensive woman develops a dry cough 6 weeks after starting ramipril. CXR normal, no other symptoms. 👉 Likely diagnosis: ACE inhibitor-induced cough. 👉 Management: Stop ACEi; switch to ARB (e.g. losartan).

Case 10 – Bronchiectasis 🌪️ A 55-year-old woman has daily productive cough with large amounts of purulent sputum and recurrent chest infections. Exam: coarse crackles, digital clubbing. 👉 Likely diagnosis: Bronchiectasis. 👉 Management: HRCT chest, sputum cultures; chest physiotherapy, mucolytics, prophylactic antibiotics if recurrent.