does not refer to a single illness, but rather a group of
conditions involving inflammation of the upper airway that leads to
a cough that sounds like a bark, particularly when a child is
Most croup is caused by viruses, but similar symptoms may
occasionally be caused by bacteria or an allergic reaction. The
viruses most commonly involved are parainfluenza virus (accounting
for most cases), adenovirus,
respiratory syncytial virus
Most children with viral croup are between the ages of 3 months
and 5 years old. Croup is most likely to occur during the fall,
winter, and early spring, and symptoms are most severe in kids
younger than 3 years of age.
Most cases of croup due to viruses are mild and can be treated
at home, though rarely it can be severe and even life-threatening.
Some kids are more prone to developing croup, especially those who
or with narrowed upper airways, and babies with a history of
breathing problems like asthma.
refers to a condition similar to viral croup, except that there are
few accompanying symptoms of an infection. The cough frequently
begins at night with a sudden onset and is often recurrent. The
child usually has no fever with spasmodic croup. The symptoms are
treated the same for either form of croup.
Signs and Symptoms
Croup is characterized by a loud
that may sound like the barking of a seal and may be accompanied by
fast or difficult breathing and sometimes a grunting noise or
wheezing while breathing.
At first, a child may have cold symptoms like a stuffy or runny
nose for a few days and may also have fever. As the upper airway
(the lining of the windpipe and the voice box) becomes
progressively inflamed and swollen, the child may become hoarse,
with a harsh, barking cough.
If the upper airway becomes swollen to the point where it is
partially blocked off, it becomes even more difficult for a child
to breathe. This happens with severe croup. With severe croup,
there may be a high-pitched or squeaking noise when breathing in
(this is called stridor). A child will tend to breathe very fast,
and the stomach or the skin between the ribs may seem to pull in
during breathing since he or she is working hard to get air in to
the lungs. The child may also appear pale or bluish around the
mouth from not getting enough oxygen. These are signs that a child
needs immediate medical attention.
Symptoms of croup often worsen at night and when the child is
upset or crying. In addition to the effects on the upper airway,
the infections that cause croup can result in inflammation further
down the airway, including the bronchi (breathing tubes) and the
Croup tends to occur in outbreaks in the fall, winter, and early
spring when the viruses that usually cause it peak. Many kids who
come in contact with the viruses that cause croup will not get
croup, but will instead have symptoms of a head cold. The viruses
that cause croup can be passed when someone coughs or sneezes.
Doctors can usually diagnose croup by looking for the telltale
barking cough and stridor, the squeaking sound on inhaling. They
will also check for fever, cold symptoms (like a runny nose), or a
recent viral illness, and ask questions to find out if the child
has a prior history of croup or upper airway problems.
If croup is severe and slow to respond to treatment, a neck
X-ray may also be taken to rule out any other reasons for the
breathing difficulty, such as a foreign object lodged in the throat
or epiglottitis (an inflammation of the epiglottis, the flap of
tissue that covers the windpipe). Typical findings on an X-ray if a
child has croup includes the top of the airway narrowing to a
point, which doctors call a steeple sign.
Most, though not all, cases of viral croup are mild. Breathing
in moist air seems to relieve many of the symptoms. Doctors will
also sometimes treat with steroids, which helps with the airway
One way to humidify the air is with a cool-mist humidifier.
Having your child breathe in the moist air through the mouth will
sometimes break a croup attack. Or try running a hot shower to
create a steam-filled bathroom where you can sit with your child
for 10 minutes. While sitting in the bathroom (but outside of the
shower), try cuddling and reading a bedtime story to help calm your
Sometimes, during cooler months, taking your child outside for a
few minutes can help break the attack because the cool air can
shrink the swollen tissues lining the airway. Parents can also try
driving the child in the car with the windows down to bring in cool
If your child has croup, consider sleeping overnight in the same
room to provide close observation. If your child is breathing
quickly, working hard to breathe, has any stridor, seems less alert
than usual, or seems to be worsening in any way, seek medical
Medical professionals will need to evaluate your child if the
croup appears serious or if there's any suspicion of airway
blockage or bacterial infection. Medications such as epinephrine or
corticosteroids may be given to reduce swelling in the upper
airways. Oxygen may also be given, and sometimes a child with croup
will need to remain in the hospital overnight for observation and
further treatment. As with most illnesses, rest and plenty of
fluids are recommended.
The symptoms of croup generally peak 2 to 3 days after the
symptoms of infection start. Croup resulting from viral infection
usually lasts less 3 to 7 days.
The vast majority of kids recover from croup with no
complications. Rarely, some will develop complications like
Children who were born prematurely or who have a history of
breathing problems or lung disease (such as asthma) are more likely
to develop severe symptoms of croup and may require
hospitalization. Croup rarely causes any long-term
and avoiding contact with people who have respiratory infections
are the best ways to reduce the chance of spreading the viruses
that cause croup.
When to Call the Doctor
Immediately call your doctor or seek medical attention if your
child has any of the following symptoms:
- difficulty breathing, including rapid breathing, belly
sinking in while breathing
- the skin between the ribs pulling in with each breath
- pale or bluish color around the mouth
- drooling or difficulty swallowing
- greater inactivity than usual when ill or less alert than
- high fever
- very sick appearance
- seems to be getting worse
Larissa Hirsch, MD
Date reviewed: May 2008
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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