Whenever your child has a cough, you probably go through the list of possible causes in your head. Is it COVID‑19? Is it strep? Is it a cold or allergies? How can you tell?
Your child could also be experiencing croup, an illness that many kids experience during the fall and winter months.
Michael Lee, M.D., pediatrician with Children's Health℠ and Professor at UT Southwestern, shares signs of croup in children and when to see a doctor.
What is croup?
Croup is an infection in the upper airway. It causes your child's voice box (larynx) and windpipe (trachea) to swell. The swelling narrows the airway and obstructs breathing, making your child's breathing very noisy, and when they cough, it sounds like a barking sound.
How do kids get croup?
Croup is mainly caused by a viral infection in your child's throat, often by the same viruses that cause the common cold (called viral croup). An allergy or acid reflux from your child's stomach can also cause croup (called spasmodic croup).
Croup is more common in younger kids aged 3 months to 5 years old. As your child grows, their airways become larger and less susceptible to croup.
What are signs of croup in kids?
Viral croup might begin like a cold, with a stuffy nose, fever and fatigue. But over time, your child will develop a cough, a hoarse or scratchy voice, and breathing that is noisy and labored. Croup caused by allergies or reflux comes on suddenly, with no previous symptoms.
Does croup cause fever?
Children with croup may have a fever that can be controlled with fever-reducing medication. Some children with croup may develop a high fever.
What does croup cough sound like?
A croup cough sounds like barking (often compared to a barking seal). Children might also have stridor, a squeaking or whistling noise when they breathe in and out.
You can find examples of both croup cough and stridor sounds online. You can compare those examples to your child's cough to help you figure out if your child might have croup. If you are concerned your child might have croup, contact your child's primary care provider. They will be able to evaluate your child's symptoms and provide a diagnosis.
Does COVID‑19 cough sound like croup?
Recent reports suggest that the Omicron variant of COVID‑19 might be causing more cases of croup in children. "It's important to remember that many respiratory viruses, like the common cold and flu, can also cause croup," says Dr. Lee.
It's not clear if the Omicron variant is the actual cause for the increase in the number of cases of croup or if the rise is because of the surge in COVID‑19 and other respiratory illnesses in general.
Croup vs. COVID‑19
Symptoms of COVID‑19 in children may be similar to many other common illnesses, including croup. Both croup and COVID‑19 can cause cold-like symptoms, fever and cough.
If your child is coughing and showing cold-like symptoms, it is best to get them tested for COVID‑19 so you can protect yourself and others. Remember, getting your child vaccinated when eligible is the best way to prevent severe COVID‑19 symptoms. If you think your child may have COVID‑19, watch for these warning signs that they need emergency care.
Is croup contagious?
Viral croup can be contagious. When your child coughs or sneezes, they may spread viruses through the air. They should be considered contagious for about 1 day before symptoms start and up to 4-5 days after their symptoms have started.
"Overall, a child with croup is less contagious when without a fever for 24 hours, when there are less symptoms and when they are feeling better," explains Dr. Lee.
Both adults and other children can get infected with the virus that causes croup. However, older kids and adults probably won't develop croup cough and stridor. An adult's airways are larger, so while swelling is uncomfortable, it doesn't make it hard to breathe.
How long does croup cough last?
Fortunately, croup is typically mild and lasts less than one week. The cough may be more severe at night.
How do you treat croup?
The sounds of stridor can scare your child, making it even harder for them to breathe. It's important you stay calm and help them calm down by hugging them or rubbing their back. You can also coach older toddlers and children through deep breaths.
If your child has a fever, make sure to give them plenty of fluids. If their fever is going up, you can give them appropriate doses of fever-reducing medications (such as acetaminophen or ibuprofen) to help bring it down. Check the label or call your pediatrician for the correct dosage for your child. See other ways to help manage fever in children.
Cool, moist air can also be soothing for a swollen throat. You can put a cool-mist humidifier in your child's room to help them breathe better at night. See other home remedies for cough in children.
If your child has severe croup symptoms, they might need a breathing treatment and/or steroids to reduce swelling. Your doctor can help you determine if your child needs this treatment.
When to go to the hospital for croup
In rare cases, swelling in your child's airway can be dangerous. You should seek immediate medical attention at an emergency room or call 911 if your child:
- Can't speak because they are struggling to breathe
- Has bluish lips or fingernails (cyanosis)
- Has stridor when lying still or sleeping
- Has excessive drool or seems to have trouble swallowing saliva
- Makes whistling noises that get louder with every breath
- Struggles to catch their breath
These are signs that your child's windpipe is swollen. "If croup progresses to having persistent stridor at rest with labored breathing, this is cause for worry, and you should take your child to the emergency room," explains Dr. Lee. A doctor can give your child medicines to take the swelling down quickly.
Learn more and get care now
The Primary Care Clinic at Children's Health℠ is here to care for all aspects of your child's health, from well-child exams and treatment of common illnesses to treatment of chronic conditions. Learn more about our primary care services.
You can also videoconference with a health care provider 24 hours a day, 7 days a week with Virtual Visit by Children's Health℠ Virtual Care. Learn more and download the Virtual Visit app today.

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