Baby Cough — What Kind & When to Worry

Common questions

• “How do I tell croup from a normal cough?” — Croup sounds like a barking seal or a small dog. Voice goes hoarse. Often there’s noise breathing IN (stridor) when severe. Peak age 6mo-3yr. Almost always worse at night and better by day.
• “Is bronchiolitis serious?” — Most healthy babies recover at home in 7-14 days. About 3% need hospital. Watch feeding (under half normal = same-day GP), breathing rate, and any colour changes. Peak day 3-5; gets worse before better. RSV is the most common cause. NICE NG9 is the standard guide.
• “How do I tell wheezing from rattly breathing?” — Wheezing is a high-pitched whistle on breathing OUT, from narrowed lower airways. Rattly / chesty noise is mucus higher up — you may feel it vibrate when you put a hand on baby’s chest. Wheeze is more concerning, especially in a baby under 1.
• “My baby has been coughing for 4 weeks — is that bad?” — Probably not. Post-viral cough commonly lasts 4-6 weeks in otherwise well babies. If they’re feeding normally, no fever, growing normally, no respiratory distress — wait it out. See GP if cough > 8 weeks, or sooner if any worry.
• “Whooping cough — how do I know?” — Coughing fits so severe the baby goes red/blue/breathless, often ending in a high-pitched WHOOP on the in-breath, often vomits at the end. Babies under 3 months may NOT whoop — they just stop breathing or go blue. Highly contagious. Maternal pertussis booster in pregnancy (16-32 weeks) cuts under-3-month pertussis by ~90%.
• “When does cough need antibiotics?” — Bacterial pneumonia (focal chest signs, high fever, focally crackly lung, RR raised, unwell child), bacterial sinusitis (uncommon under 6), confirmed pertussis. Most coughs are viral and antibiotics do nothing.
• “Is steam / a humidifier good for cough?” — Sitting in a steamy bathroom can help acute croup attacks (5-10 minutes). Whole-room humidifiers have weak evidence; if you use one, change water daily (mould risk).
• “Should I try honey?” — Yes if over 12 months. 2.5-5 ml of honey 30 min before bed has Cochrane-reviewed evidence for reducing cough severity in older infants. Under 12 months: NEVER (infant botulism risk).
• “Can I take baby outside with a cough?” — Yes, fresh air can help, especially for croup. Wrap warmly. Avoid smoky / polluted areas. Skip swimming until recovered.
• “When does cough mean nursery should keep them home?” — Cough alone usually OK to attend if otherwise well. Stay home if fever, listless, persistent vomiting, breathing problems, or confirmed pertussis / chicken pox / measles.
• “Asthma at this age?” — Asthma is hard to diagnose under 5. Recurrent wheeze with viruses is common ("viral-induced wheeze") and most outgrow it. Suggests asthma if eczema / family atopy / persistent symptoms / wheeze between viruses / responds to inhaler.
• “Why does the cough get worse at night?” — Lying flat pools mucus; circadian dip in steroid levels; air tends to be drier. Croup classically gets worse at 1-3am. Try sitting upright with the baby to settle.
• “COVID-19, RSV, flu — do I need to know which?” — For most healthy children, no — management is supportive. RSV bronchiolitis follows NICE NG9; influenza may warrant antivirals in high-risk groups; COVID is usually mild in children. Test only if changes management.