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🌬️ Childhood illness guide

Croup

A barking cough and hoarse voice that sounds worse than it usually is

EW

By Emma Whitfield · Pregnancy & Baby Writer

What it is

Croup is a common condition that mainly affects babies' and young children's airways, causing swelling around the voice box and windpipe. It sounds alarming — but it's usually mild.

Symptoms

  • A barking cough that can sound like a seal
  • A hoarse voice
  • Difficulty breathing
  • A high-pitched, rasping sound when breathing in (stridor)
  • Often starts with cold-like symptoms — a temperature, runny nose and ordinary cough

How long it lasts

Croup usually gets better on its own within 48 hours.

What helps at home

  • Sit your child upright rather than letting them lie down
  • Stay calm and keep them calm — distress can make breathing feel harder
  • Offer plenty of fluids
  • Check on them regularly, including during the night
  • Give paracetamol or ibuprofen if they need it for discomfort
  • Don't put them in a steamy room or have them inhale steam — the NHS specifically advises against this

See a GP if

  • You think your child may have croup — a doctor can prescribe medicine to shorten the illness
  • Your child is getting worse, or isn't improving after already seeing a GP

Call 999 or go to A&E if your child:

  • Is struggling to breathe — grunting, sucking in under the ribs, or breathing that sounds different
  • Has blue, grey, pale or blotchy skin, lips or tongue (on brown or black skin this can be easier to see on the palms or soles)
  • Is sleepier than normal or difficult to wake
  • Is unusually quiet and still, or is limp, floppy or not responding normally
  • Is very upset or restless, struggling to breathe, and can't be calmed down
  • Is drooling more than usual, finding it hard to swallow, or wants to sit rather than lie down

Contagious period & nursery/school

The NHS doesn't set a specific stay-off-nursery period for croup — as a rule of thumb, keep your child home while they're feeling unwell, and check with your nursery or school if you're unsure.

Croup: common questions

What is croup?

Croup is a common condition that mainly affects babies' and young children's airways, causing swelling around the voice box and windpipe. It sounds alarming — but it's usually mild. Croup usually gets better on its own within 48 hours. This is general information, not a diagnosis — see a GP or call NHS 111 if you're unsure.

What are the symptoms of croup?

A barking cough that can sound like a seal A hoarse voice Difficulty breathing A high-pitched, rasping sound when breathing in (stridor) Often starts with cold-like symptoms — a temperature, runny nose and ordinary cough

When should I call 999 for croup?

Call 999 or go to A&E if your child: Is struggling to breathe — grunting, sucking in under the ribs, or breathing that sounds different Has blue, grey, pale or blotchy skin, lips or tongue (on brown or black skin this can be easier to see on the palms or soles) Is sleepier than normal or difficult to wake Is unusually quiet and still, or is limp, floppy or not responding normally Is very upset or restless, struggling to breathe, and can't be calmed down Is drooling more than usual, finding it hard to swallow, or wants to sit rather than lie down

Sources & further reading

This is general information sourced from NHS.uk, not medical advice or a diagnostic tool. Every child is different — if you're at all worried, contact your GP, call NHS 111, or in an emergency call 999. Reviewed July 2026.