Croup in Kids: Barking Cough, Night Care and When to Go to the ER • Living Life as Moms | Mom Hacks, Toddler Snacks, and Kids Activities

Quick answer: croup is a viral infection of the upper airway that swells the voice box and windpipe, causing a barking, seal-like cough, a hoarse voice and sometimes a high-pitched sound when a child breathes in. It is most common in children between six months and three years old and is often worse at night. Most cases are mild and last three to five days. Keep your child calm, offer fluids and call the doctor, who may prescribe a steroid. Call 911 or go to the emergency room if your child has noisy breathing while resting, pulling in at the ribs or neck, blue lips, drooling or extreme sleepiness.

Few sounds wake a parent faster than a barking cough in the middle of the night. A child who was fine at bedtime suddenly sounds like a seal, with a raspy voice and noisy breathing. It is frightening, and it is also one of the most common childhood illnesses in the fall and winter. Knowing what croup is, what you can do at home and when to get help makes a scary night much easier to manage. This guide is part of our family health and safety guide.

Sources: American Academy of Pediatrics (AAP) HealthyChildren.org guidance on croup; Centers for Disease Control and Prevention (CDC) information on human parainfluenza viruses; Mayo Clinic and MedlinePlus pages on croup; U.S. Food and Drug Administration (FDA) advice on cough and cold medicines for children. This article is general information, not medical advice. If you think your child is struggling to breathe, call 911.

What Is Croup?

Croup is a respiratory illness that causes swelling in the larynx (voice box) and trachea (windpipe), just below the vocal cords. A child’s airway is narrow, so a small amount of swelling can change the sound of the voice and the cough and, in more serious cases, make breathing harder.

Doctors sometimes call it laryngotracheitis. In most children, croup is caused by a virus. The most common is parainfluenza virus, which circulates mostly in the fall and early winter, though other viruses such as influenza, RSV, adenovirus and the viruses that cause common colds can also cause croup.

Who gets croup?

Croup is most common in children between six months and three years of age, because their airways are small. Older children can get it, but they usually have milder symptoms. Boys get croup slightly more often than girls. Many children have croup more than once.

Croup Symptoms

Croup often starts like an ordinary cold, with a runny nose, mild fever and cough. After a day or two, the cough changes. Typical symptoms include:

A barking cough: a harsh, seal-like sound that is very distinctive.
A hoarse or raspy voice: the voice sounds rough or weak.
Stridor: a high-pitched, squeaky sound when the child breathes in. It is often heard when the child cries or coughs, and in more serious croup it can be heard even at rest.
Low-grade fever: often between 100 and 102 degrees Fahrenheit.
Symptoms that are worse at night: croup often flares in the evening and overnight, and children may look better in the morning.
Trouble breathing in some cases: in more serious cases, the child may breathe fast or show signs of struggle.

Children with mild croup have the barking cough and hoarseness but breathe comfortably. Moderate and severe croup involve stridor at rest and visible effort to breathe.

How Long Does Croup Last?

Most children recover in three to five days. Symptoms are usually the worst on the second or third night and then improve. A cough can linger for a week or more. If symptoms last much longer, or if your child gets worse after seeming better, call the doctor.

Is Croup Contagious?

Yes. The viruses that cause croup spread through coughs, sneezes, shared toys and unwashed hands. A child is usually most contagious in the first few days of illness. Many schools and child care centers ask that children stay home while they have a fever and until they feel well enough to take part in activities. Our guide on when to keep your child home from school explains common rules.

What to Do at Home

For mild croup, the doctor will often recommend care at home. These steps can help.

Stay calm and keep your child calm

Crying and agitation can make the airway swell and the breathing noisier. Holding your child, rocking, reading a book or singing softly helps. Your calm voice and body language matter. Let your child sit upright on your lap, which many children find easier than lying flat.

Offer fluids

Offer water, breast milk or formula, or warm, clear drinks to older children, in small, frequent sips. Fluids keep the throat moist and prevent dehydration. Do not force a child to drink if breathing is fast or difficult.

Try cool air or a steamy bathroom, with caution

Many parents have heard that a steamy bathroom or cold night air helps. Studies have not shown that humid air reliably treats croup, and the AAP does not consider it a proven treatment. Some families find that stepping outside into cool night air, or sitting in a bathroom filled with steam from a hot shower, seems to calm a child. If you try the bathroom, stay with your child and keep the water far enough away that your child cannot get burned. Do not use hot steam vaporizers or hot water bowls near children, because they can cause serious scalds.

A cool-mist humidifier in the bedroom is a safer option for comfort and for dry winter air, although it has not been proven to treat croup. Clean it regularly according to the instructions.

Elevate the head carefully

An older child can sleep with a slightly raised head if the doctor agrees. Never put pillows or wedges in an infant’s crib. Safe sleep rules for babies still apply, so ask the doctor before changing anything.

Treat fever and discomfort

Fever reducers such as acetaminophen or ibuprofen may be used if your child is over the minimum age on the label and the dose is based on weight. Ask the doctor for the right amount.
Never give aspirin to a child.
Our guide to fever in kids and when to call the doctor explains what temperatures matter.

Avoid cough and cold medicine

The FDA and the AAP advise against giving over-the-counter cough and cold medicines to children under four years old, because they have not been shown to work and may cause serious side effects. Cough suppressants are not helpful for croup anyway, since the cough is part of how the child clears the airway.

What Doctors Do for Croup

Children with croup should see a doctor, especially the first time or if symptoms seem more than mild. Treatment depends on severity.

Examination: the doctor listens to breathing, checks oxygen levels and looks for signs of struggle.
Steroid medicine: a single dose of an oral steroid such as dexamethasone is the standard treatment for most children with croup. It reduces swelling and often improves breathing within a few hours. The effect can last for a day or two.
Nebulized epinephrine: for moderate to severe croup, a child may breathe in medicine as a mist, which can quickly reduce swelling. Children who receive it are usually observed for several hours afterward.
Oxygen: if blood oxygen is low.
Hospital care: a small number of children need to stay in the hospital for observation or more treatment.
Antibiotics: these are not used unless there is a bacterial complication, because croup is viral.

Chest or neck X-rays are not usually needed, although a doctor may order one if the diagnosis is unclear.

Warning Signs: When to Call 911 or Go to the ER

Call 911 or go to the nearest emergency room right away if your child:

Has noisy, high-pitched breathing (stridor) while resting or sleeping
Has trouble breathing, breathes very fast or seems to be working hard
Pulls in the skin between the ribs, below the ribs or at the base of the throat with each breath
Has blue, gray or very pale lips or skin
Drools, cannot swallow or sits leaning forward with the neck stretched out
Is unusually sleepy, hard to wake, limp or very agitated
Cannot speak, cry or cough with sound
Seems to be getting worse instead of better

Also call the doctor quickly if your child has a high fever, shows signs of dehydration, such as no urine for many hours, or has croup symptoms and is less than six months old. Rarely, a different condition such as epiglottitis or an object in the airway can look like croup, which is another reason to seek care if your child looks very ill. Our guide on how to teach kids to call 911 helps older children know what to do in an emergency.

A Night Plan for Parents

When croup strikes after midnight, a simple plan helps.

Stay calm, and keep your child upright and comfortable.
Listen and watch. Check whether the breathing is quiet when your child is calm.
Call the doctor’s after-hours line, and describe the symptoms. Many practices have a nurse line.
Try cool night air or a steamy bathroom for a few minutes if your child seems to find it soothing, with close supervision.
Give fluids if your child can drink comfortably.
Follow the doctor’s instructions about steroids or a visit.
Call 911 if you see any of the warning signs above.
Rest nearby. Many parents sleep in the child’s room, or have the child sleep near them, for a night or two to watch the breathing.

Croup Versus Other Illnesses

Several conditions can resemble croup. A doctor can help tell them apart.

Common cold: a runny nose and cough without the barking sound.
RSV and bronchiolitis: mostly affect babies and cause wheezing and fast breathing. See our guide to RSV in babies and young kids.
Asthma: causes wheezing, usually on breathing out, and often repeats after triggers like exercise or allergens.
Whooping cough (pertussis): causes long coughing fits, sometimes with a whooping sound. Vaccines help prevent it.
Epiglottitis: a rare, serious bacterial infection that causes drooling and severe distress. It has become uncommon since the Hib vaccine.
Foreign object in the airway: sudden coughing or choking, often in a toddler who was eating or playing with small items.

Can You Prevent Croup?

There is no vaccine for the viruses that most often cause croup, but several habits reduce the chance of infection and complications:

Wash hands often, and teach children to wash their hands before eating and after coughing or sneezing.
Keep sick children away from others where possible.
Clean shared toys and surfaces during illness.
Keep childhood vaccines up to date, including the flu shot each year. Vaccines such as Hib, DTaP and measles protect against illnesses that can cause serious airway problems.
Avoid tobacco smoke, which irritates children’s airways.

When Croup Keeps Coming Back

Some children get croup several times. Repeated episodes are usually due to a narrow airway that grows out of the problem as the child gets older. If your child has repeated or severe attacks, talks about breathing problems when not sick or has noisy breathing that never goes away, ask the doctor about an evaluation. A specialist may want to look for an anatomic cause, allergies or reflux.

Looking After Yourself

A night of barking coughs and worry is exhausting. After the worst has passed, take time to rest, eat and drink water. Ask a partner, relative or friend to help for a day if you can. Once your child recovers, write down what helped, the number of the after-hours line and the signs that worried you, so you feel prepared next time.

Frequently Asked Questions

What does a croup cough sound like?

A croup cough is harsh and barking, often compared to the sound of a seal. The voice may also sound hoarse.

Does cold air help croup?

Some families find that stepping outside into cool night air calms a child, but studies have not proven that cold air or steam treats croup. The doctor may prescribe a steroid, which is the proven treatment.

Can croup go away on its own?

Many mild cases improve on their own in three to five days, but children should still be seen by a doctor, especially if it is the first time or if breathing seems hard.

Is croup an emergency?

Usually not, but it can be. Call 911 or go to the emergency room for noisy breathing at rest, pulling in at the ribs or neck, blue lips, drooling or extreme sleepiness.

How long is a child contagious with croup?

Children are most contagious in the first few days, especially while they have a fever. Keep them home until the fever is gone and they feel well enough for normal activities.