It can be incredibly nerve-wracking when your baby or toddler comes down with a bad cough, and decoding your child’s cough symptoms can be tricky. Is it a cold? The flu? COVID-19? Or something else like whooping cough, croup or RSV?

Fortunately, croup does have some telltale signs and symptoms and treatments that can bring some relief. Here’s what you need to know. 

What is croup?

Croup (laryngotracheobronchitis) is primarily a viral infection that causes inflammation in the voice box (larynx) and windpipe (trachea). This causes the airways just below the vocal cords to swell and narrow — making breathing difficult and producing a harsh, barking cough.

Babies, toddlers and preschoolers between the ages of 3 months and 5 years are most at risk for croup due to their tiny airways, but anyone can get it at any age. The illness shows up most frequently in the colder months — between October and March.

Most cases of croup are not serious, but a severe case can require hospitalization.

What causes croup in babies and toddlers?

Croup is most often caused by respiratory viruses, including:

The Omicron variant's spread has correlated with increased reports of croup in children with COVID-19, but croup in children is most often caused by the parainfluenza virus, a different respiratory virus.

Genetics may also play a role in whether a baby or toddler catches croup. Were you or one of your siblings babies with croup? Talk to your family to find out your history. 

Some children may have recurrent episodes of croup. Hopefully, your little one doesn’t fall into that category, but if he does, you might want to ask your pediatrician if it’s time to see a pediatric otolaryngologist (ENT doctor) for a thorough evaluation of the upper airway. Structural abnormalities can be a cause of recurrent croup.

What are the symptoms of croup in babies and toddlers?

Croup usually begins like the common cold — runny nose, maybe a fever, and plenty of irritability. But after a few days, your child’s voice or cries may sound hoarse. Then comes the barking seal cough — which may be accompanied by labored or noisy breathing, including a high-pitched squeaky sound when your child inhales (called stridor).

Here are the symptoms of croup:

  • Hoarse, raspy voice
  • Stuffy or runny nose 
  • Difficulty swallowing
  • Irritability
  • Fever (sometimes)
  • Barking cough that sounds like a seal (usually worse at night) 
  • Shortness of breath 

If your child has symptoms of croup, call your pediatrician for an appointment. Babies who are born prematurely are most at risk for complications. 

How is croup diagnosed?

Unlike whooping cough, doctors are typically able to diagnose croup simply by listening to a cough and getting a health history. 

Your child may need more tests if the pediatrician thinks he has another illness, such as pneumonia or COVID-19. These tests include:

  • COVID test
  • Neck or chest X-rays
  • Blood tests 
  • Pulse oximetry

Is croup contagious?

Yes, croup is contagious. Your child (and you) can become exposed by direct contact with an infected person — especially if that little person coughs or sneezes on them or gives them a hug or a high-five. Croup germs can also survive on surfaces (e.g. doorknobs, toys, shared drinks.) 

Croup is usually contagious for three days after symptoms start or until the infected person is fever-free. So pack it in and get ready for at least a three-day quarantine from day care, preschool and other activities.

How long does croup last?

Croup in children generally lasts from several days up to a week, and it may recur. 

In general, mild cases of croup go away by themselves and can be managed at home. (And no, you don’t need antibiotics. Croup is almost always caused by a virus, not a bacteria). 

If your child’s croup is severe, or if he isn't breathing well, hospital care may be needed. Always call your pediatrician with any questions or concerns.

Treatments for croup in babies and toddlers

You can treat most cases of croup at home. Though the cough may sound scary, these simple measures will usually relieve discomfort in your barking baby or toddler:

  • Hang out in a steamy bathroom. Take your child into the bathroom, get a hot shower running and close the door. Then stand together in the steamy bathroom (not in the shower) for 15 to 20 minutes. The warm moist air should lessen the inflammation in the airways and make breathing easier.
  • Go out into the night air. On a cool evening, you could also take your little one outside into the fresh air for 15 minutes, or open the freezer and have him breathe in the air for several minutes. You can also try cracking the window open or turning on the ceiling fan if you have one.
  • Use a humidifier. Run a cool-mist humidifier in baby’s room when he’s asleep at night. Use filtered or distilled water and don’t forget to clean it daily with a bleach-and-water solution.
  • Stay upright. Try to keep your little one in an upright position while he's awake, because it makes it easier to breathe. Strap your baby or toddler in his high chair or another seat. At night and during naptime, steer clear of pillows and other devices designed to help your child's head stay elevated, as they can be dangerous.
  • Avoid dehydration. Give your child plenty of fluids to soothe his throat. Offer breastfed babies under 6 months old more frequent feeds and those over 6 months more frequent feeds plus sips of water in between. For formula-fed babies under 6 months, offer the usual amount of formula in smaller but more frequent feeds, and do the same for those over 6 months along with sips of water between feeds. For babies and toddlers over 1 year, offer water or a rehydration fluid like Pedialyte, possibly in smaller, more frequent amounts (like a few sips every 15 minutes or so).
  • Comfort and cuddles. When dealing with croup in children, do your best to keep your little one calm (read stories, sing songs or cuddle). Crying can make breathing difficulties worse.
  • Try some honey. If your child is over 12 months, give 1 teaspoon of honey before bedtime to help ease their throat from the coughing. Never give honey to babies under 1 year.
  • Fight fevers. If your little one has a fever, check with your pediatrician about giving her acetaminophen (Tylenol) to bring it down to normal.

How to prevent croup in babies and toddlers

Though it's not always possible to prevent croup in your baby or toddler, here's what you can do to reduce your child's risk of getting sick:

Practice good hygiene

Like many other respiratory illnesses, croup spreads by coughing and sneezing in close contact with others who then breathe in the bacteria. To practice good hygiene, teach your little one to cover his mouth and nose when he coughs or sneezes using a tissue (or the inside of his elbow).

You’ll also want to school him in proper hand washing after blowing his nose, coughing or sneezing. Use an alcohol-based hand sanitizer if soap and water are not available. Modeling this behavior and coaching when needed will help the healthy habits stick.

Steer clear of anyone who is sick

Your little one’s immune system is vulnerable to all sorts of germs. Don’t hesitate to ask any well-meaning but feeling-under-the-weather friends or relatives to postpone visits to your house until they’re completely recovered.

Get your child vaccinated

Because the influenza virus can sometimes cause croup, a flu shot might reduce the chance of your child developing the condition. The American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) recommend a flu vaccine every year for all children 6 months and older.

Kids older than 5 should also receive the COVID-19 vaccine. Parents of younger children can help protect their littlest ones by getting the flu and COVID vaccines themselves.

A vaccine against parainfluenza viruses, the most common croup-causing viruses, is not currently available. In the first few months of life, infants do have protection against some types of parainfluenza because of antibodies from their mothers.

When should I go to the doctor for croup?

Whenever you suspect croup in your baby or toddler, call the doctor for a diagnosis. Be sure to get in touch if you see any of these symptoms:

  • The steam or cold air doesn’t stop the barky, croupy cough
  • Your child lacks good color, or there’s a bluish or grayish hue around your child’s mouth, nose or fingernails
  • You hear stridor (the high-pitched breathing sound) during the day, or the nighttime stridor doesn’t promptly go away with exposure to steam or cold
  • Your child has difficulty catching his breath, especially during the day
  • You notice retractions, which is when the skin between the ribs pulls in with each breath
  • Your baby has signs of dehydration (like crying without tears and few wet diapers)

If your child’s croup seems especially severe or doesn’t improve with these suggested treatments, your pediatrician may prescribe steroids to relieve swelling in the airways and make breathing easier. Hospitalization is sometimes required in more serious cases.

You know your child best, so trust your instincts if your little one doesn’t seem well. If he's having trouble breathing, has pale or blue skin or lips, or is drowsy or hard to wake up, call 911 or take him to the emergency room right away.