Understanding Croup: What Parents Should Know
If your child has ever woken suddenly in the middle of the night with a harsh, barking cough that sounds like a seal, you know how frightening it can be. The noise can echo through the house, and your child may look panicked or struggle to catch their breath. This common childhood illness, known as croup, can be alarming—but the good news is that most cases are mild, short-lived, and respond well to simple home remedies.
What causes croup?
Croup is usually caused by a viral infection that leads to inflammation and swelling in the upper part of the airway—specifically around the vocal cords (larynx), the windpipe (trachea), and sometimes the upper bronchi. The most common culprit is the parainfluenza virus, but croup can also be caused by other viruses such as respiratory syncytial virus (RSV), influenza, adenovirus, or even COVID-19. The swelling makes the airway narrower, especially in young children whose airways are already small. This is what causes the characteristic barking cough, hoarse voice, and the high-pitched noise called stridor when your child breathes in.
Symptoms often worsen at night, when airways naturally narrow a bit and the cooler, drier air irritates the throat. A child who seemed fine at bedtime may suddenly wake up coughing and struggling to breathe, which is why these nighttime episodes can be so distressing for parents.
Who gets croup—and when is it most severe?
Croup is most common in children between 6 months and 3 years of age, with the peak around the second year of life. This age group is especially vulnerable because their airways are small and easily narrowed by even mild swelling. As children grow, their airways widen, and croup tends to cause only mild hoarseness or a typical “cold” in older children and adults.
Croup can occur any time of year but is most common during the fall and early winter months, often appearing alongside other respiratory viruses. Most cases are mild, but a small percentage can become severe and require medical attention.
Recognizing the symptoms
Croup usually starts with a mild cold—runny nose, congestion, and a low-grade fever. After a day or two, the classic symptoms appear:
A barking cough, often described as “seal-like.”
A hoarse voice.
Stridor, a high-pitched sound when breathing in, especially noticeable when the child is upset or crying.
Labored breathing—you may see the skin pulling in around the ribs or collarbone with each breath.
Difficulty sleeping due to coughing fits, which often worsen at night.
In most children, these symptoms last for about 3 to 5 days, though the cough may linger for up to a week.
Home care and comfort measures
Most cases of croup can be managed at home, and knowing what to do can make a big difference. The main goal is to keep your child calm and help reduce airway inflammation.
Cool, humidified air: Run a cool mist humidifier in your child’s bedroom at night to keep the air moist. Alternatively, you can sit with your child in a steamy bathroom for 5–10 minutes—run the hot shower, close the door, and let them breathe in the warm mist. This can loosen mucus and calm the cough.
Exposure to cool outdoor air: If your child suddenly wakes at night struggling to breathe, wrap them in a blanket and step outside into the cool night air for a few minutes. The temperature change can help the airway swelling subside. If it’s not practical to go outside, opening the freezer door and letting your child breathe in the cool air can have a similar effect.
Hydration: Encourage your child to drink fluids frequently—water, breastmilk, or clear broths—to prevent dehydration, which can worsen symptoms. Popsicles and warm liquids like soup can be soothing as well.
Keep your child calm: Crying and distress can make symptoms worse by tightening the airway muscles. Hold your child upright, comfort them with a calm voice, and help them relax.
When to seek medical care
While most cases of croup can be treated at home, some children may need medical attention. Call your doctor or go to urgent care or the emergency room if your child:
Has stridor at rest (noisy breathing even when calm).
Is working hard to breathe, with visible pulling in of the skin around the ribs or neck.
Has bluish lips or fingernails.
Is drooling or having trouble swallowing.
Appears exhausted or unusually sleepy.
In the clinic or emergency department, your child may receive a steroid medication, usually dexamethasone (Decadron), to reduce swelling around the vocal cords. The medication usually starts working within a few hours and can make a dramatic difference, with improvement lasting up to 72 hours. In more severe cases, nebulized epinephrine may be given to rapidly decrease airway swelling. Fortunately, these treatments are highly effective, and most children can return home after evaluation.
The outlook
Croup usually runs its course within a few days, though the cough may linger for up to a week. Most children recover fully without complications. Because croup is caused by viruses, antibiotics are not helpful, but supportive care and time are. Once you’ve experienced it once, you’ll be better prepared for what to do if it happens again.
Even though the barking cough of croup can sound frightening, remember that it’s almost always temporary and treatable. With calm reassurance, cool air, hydration, and—when needed—a dose of dexamethasone from your healthcare provider, your child will soon be breathing easier and back to normal.
