Few sounds are as alarming to a parent as a child who wakes up in the middle of the night with a cough that sounds like a barking seal. That distinctive cough is the hallmark of croup, a common childhood illness that is especially frequent in the fall and winter. Croup can be scary, but most cases are mild and can be managed at home. Knowing what to expect, and which signs mean your child needs help quickly, can make those long nights much easier.
What Is Croup?
Croup is an infection that causes swelling in the voice box (larynx) and windpipe (trachea), the upper part of the airway just below the throat. In young children, this part of the airway is narrow, so even a small amount of swelling can make breathing noisy and the cough harsh.
Croup is usually caused by viruses, most often parainfluenza viruses, although other respiratory viruses, including influenza, RSV and COVID-19, can also cause it. It most often affects children between 6 months and 3 years of age, but it can occur up to about age 5 and occasionally in older children. Some children get croup more than once.
Symptoms of Croup
Croup often begins like a regular cold, with a runny nose, mild cough and sometimes a low fever. After a day or two, the classic symptoms appear:
- A loud, barking cough that sounds like a seal
- A hoarse voice or cry
- Stridor: a high-pitched, squeaky or harsh sound when breathing in
- Symptoms that are often worse at night and when the child is upset or crying
Croup symptoms typically last 3 to 5 days and are usually worst on the first two or three nights. The cough may linger in a milder form for up to a week.
How Croup Spreads
The viruses that cause croup spread through coughs, sneezes and contact with contaminated hands and surfaces. Older children and adults who catch the same virus usually just get a cold, because their larger airways are less affected by swelling. Handwashing, covering coughs and keeping sick children home help prevent spread. Staying up to date on vaccines, including the yearly flu vaccine, protects against some infections that can cause croup-like illness.
Home Care for Mild Croup
Most children with croup have mild symptoms: a barking cough with no stridor or only occasional stridor when crying. These children can usually be cared for at home.
Stay calm and comfort your child
Crying and anxiety make croup worse because they increase the effort of breathing. Hold your child, read a story, sing or offer a favorite toy. Your calm voice is one of the best treatments.
Try cool air
Many parents find that breathing cool night air seems to help: bundle your child up and sit outside or near an open window for a few minutes, or use a cool-mist humidifier in the bedroom. Research has not proven that mist or cool air shortens croup, but these steps are safe and some children find them soothing. Avoid hot steam, which can cause burns.
Keep your child upright and hydrated
Sitting upright can make breathing more comfortable. Offer fluids frequently.
Treat fever and discomfort
Acetaminophen or ibuprofen (for children 6 months and older) can ease fever and discomfort. Give the correct dose for your child's weight. Cough medicines don't help croup and are not recommended for young children.
Sleep nearby
Because croup tends to worsen at night, consider sleeping in the same room as your child for the first couple of nights so you can hear changes in breathing.
How Doctors Treat Croup
If your child has croup with stridor or more than mild symptoms, your pediatrician may prescribe a single dose of a steroid medicine (such as dexamethasone), given by mouth or by injection. Steroids reduce swelling in the airway and can make breathing easier within a few hours, with effects lasting a day or more. Children with moderate to severe croup may receive a breathing treatment with epinephrine in the emergency department and be watched for several hours. A small number of children need to stay in the hospital.
Antibiotics are not used for croup because it is caused by viruses.
When to Call 911 or Go to the Emergency Department
Get emergency help immediately if your child:
- Has stridor (noisy breathing in) while resting or calm, not just when crying
- Is working hard to breathe, with the skin pulling in between the ribs, above the collarbone or at the base of the neck
- Has blue or gray color around the lips or face
- Is drooling, has trouble swallowing or can't speak or cry
- Is unusually sleepy, limp, very agitated or hard to wake
- Seems to be getting worse quickly
When to Call the Pediatrician
Contact our office if your child:
- Has stridor that comes and goes, even if it improves at home
- Has a fever lasting more than 3 days, or a fever of 104°F (40°C) or higher
- Has croup symptoms that last longer than a week, or keeps getting croup
- Is younger than 6 months
- Is not drinking well or has fewer wet diapers
Croup or Something Else?
Other conditions can cause noisy breathing, including an inhaled object, a severe allergic reaction, or rare infections of the epiglottis or windpipe. If your child suddenly starts coughing or choking while eating or playing with small objects, or if swelling of the face or lips appears, seek emergency care. Children with frequent episodes of croup-like symptoms without a cold should be evaluated, because asthma or airway differences can sometimes be involved. Learn more about signs of asthma in children.
Frequently Asked Questions
Is croup contagious?
Yes. The virus that causes croup is contagious, usually for a few days after symptoms begin and while your child has a fever. Keep your child home until they are fever-free and feeling better.
Can adults get croup?
Adults can catch the same viruses, but they usually develop cold symptoms rather than croup.
Will my child outgrow croup?
Yes. As children grow, their airways get larger, and croup becomes much less common after age 5.
The Bottom Line
Croup is common, usually mild and often frightening mostly because of how it sounds. Calm comfort, fluids and close watching at night are the mainstays of home care. Watch especially for noisy breathing at rest and signs that your child is working hard to breathe. If you are ever unsure, trust your instincts and seek care. For other respiratory illnesses this season, read our guides on RSV in babies and cold vs. flu.
This article is general health information for parents and is not a substitute for medical advice. If you are worried about your child, contact your pediatrician; in an emergency, call 911.
Questions about your child's health?
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