Croup: the barking cough, what to do at 2am, and when to get help fast
Last updated September 3, 2026.
Croup sounds terrifying and is usually manageable: the seal-like barking cough and noisy breathing come from a virus swelling the windpipe, and most children ride it out at home in a couple of nights. It mainly hits children between 6 months and 3 years, typically starting as an ordinary cold before the cough arrives at night. Your calm is genuinely part of the treatment: crying narrows the airway further and makes the noisy breathing worse.
What does it look like?
The cough is unmistakable once heard: a harsh bark, like a seal. Add a hoarse voice and, in more significant cases, stridor, a harsh or squeaky noise when breathing in. It comes on at night after a day or two of cold symptoms, is usually worst on the first one to two nights, and most children are much better within about 48 hours, with the cold symptoms trailing a few days longer. A mild fever is common. Between coughing bouts, a child with mild croup is alert, drinking, and breathing comfortably.
What actually helps?
- Keep them calm and upright: sit your child on your lap, upright, and comfort them. Crying and panic worsen the stridor; a settled child breathes easier. This is the main home treatment.
- Comfort measures: offer cool water to sip, keep clothing light, and paracetamol or ibuprofen (dosed by weight) settles fever and discomfort. Many parents find cool night air from an open window briefly eases the stridor.
- Skip the steam: steaming over a bowl or in a hot bathroom has no good evidence and causes scald injuries every year; guidance now advises against it. Cough medicines do not help croup.
- Sleep nearby the first night or two: croup peaks at night, so having your child in your room or checking regularly lets you hear if the breathing worsens.
- Steroids when it is more than mild: a single dose of steroid medicine (dexamethasone or prednisolone) from a doctor or hospital is highly effective for children with stridor or real breathing effort, and reduces the night-aerial-acrobatics phase dramatically. That requires being seen, which is the point of the red flags below.
When is it an emergency?
Call 999 (or 911/112) if your child: is struggling to breathe (skin pulling in between the ribs, under the ribs, or at the base of the throat; using tummy muscles to breathe), has constant stridor even when calm and resting, is drooling or cannot swallow, looks blue or very pale around the lips, is unusually drowsy or limp, or is too breathless to talk or cry. A first episode of significant stridor at rest warrants same-day assessment even if it settles. Trust the sound: parents who say the breathing sounds wrong are usually right. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
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Common questions
What is croup?
Croup is a viral infection that swells the voice box and windpipe just below it, which is why the cough sounds like a seal barking and breathing in can be noisy (stridor). It mainly affects children between 6 months and 3 years, whose airways are narrowest, and typically starts as a cold before the cough arrives at night. Most cases are mild and settle within about 48 hours, though the cold can linger. Older children and adults get the same viruses as ordinary colds because their airways are wide enough.
How long does croup last?
The barking cough and any stridor are usually worst on the first one to two nights, and most children are clearly better within about 48 hours, with the cough gone within roughly 3 to 5 days. Some children have a milder second peak the following night. The runny nose and general cold symptoms can trail for a week or so. Cough persisting well beyond that, or repeated croup episodes, deserves a doctor's look.
Is croup contagious?
The virus that causes it is: it spreads like any cold, through coughs, sneezes, and hands. What is not contagious is the croup itself; another child who catches the virus will most likely get an ordinary cold, and only the age group with narrow airways gets the barking version. Standard cold hygiene applies, and a child can return to school or nursery once they are well enough and any fever has settled.
What can I do for croup at home, and what about steam?
Keep your child calm (crying worsens the breathing noise), sit them upright, offer cool sips, dress them lightly, and give paracetamol or ibuprofen for fever or discomfort. Stay nearby at night during the first couple of nights. Do not use steam: bathroom steam and bowls of hot water have no proven benefit and scald children every year. Cough medicines do not work for croup and are not recommended for young children. Many parents find a few minutes of cool night air from an open window eases an episode.
When should I take my child to hospital for croup?
Call 999 (or 911/112) for: real struggle to breathe (skin pulling in between or below the ribs or at the throat base), stridor that is present even when your child is calm and resting, drooling or inability to swallow, blue or very pale lips, unusual drowsiness or limpness, or being too breathless to cry or talk. A child with milder croup who is drinking and alert can be watched at home; a first episode that worries you is always a fair reason for a same-day assessment.
Will my child keep getting croup?
Some children are prone to it: repeated episodes with different viruses are common in the toddler years, and some children get 'spasmodic croup,' sudden nighttime barking without much cold, which may overlap with asthma tendencies. Children typically grow out of it by school age as the airway widens. Very frequent episodes, episodes outside the typical age range, or stridor that persists between colds should be checked for other causes.
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