Croup: A-to-Z Guide from Diagnosis to Treatment to Prevention

Sick child. With a barking cough, it could be croup.

Introduction to croup:

Picture this scene: A couple is spending a quiet evening at home with their one-year-old daughter, who has had a bit of a cold. At about 8 o’clock she begins coughing — an unusually loud, resonant cough. Over the next few hours, the sporadic cough becomes increasingly frequent. She gets a fever. At 11 o’clock (when all the After Hours Clinics have closed, and her doctor is in bed), her breathing becomes noisy and labored. Each breath now makes a worrisome crowing noise unlike anything the parents have ever heard. Concerned, they bundle her up and take her to the local emergency room.

As they are pulling into the ER driveway, they notice that the child seems much, much better. After some heated debate (during which the little girl falls asleep peacefully), they decide to head home without being seen. An hour later, at home, the little girl is woken up by the loud cough, and her breathing is even more difficult…

What is it?

Croup, bronchiolitis, bronchitis, and pneumonia are all words that denote the location in the body of a problem. Bronchiolitis refers to inflammation in the bronchioles, the smaller airways that branch off from the main bronchi or breathing tubes. Bronchitis is inflammation in these larger, main breathing tubes. Pneumonia refers to inflammation of the lungs themselves.

The word croup comes from an old Germanic word for the voice box. Today, croup, or laryngotracheobronchitis, refers to swelling centered at the larynx or vocal cords. Infection, allergy, or an inhaled foreign body can cause croup. GE reflux can trigger croup.

It is usually (75 percent of the time) caused by parainfluenza viruses, but RSV, measles, adenovirus, and influenza can all cause croup.

Before the era of immunizations and antibiotics, croup was a dreaded and deadly disease, usually caused by the diphtheria bacteria. Today, most cases of croup are mild. Nevertheless, it can still be a dangerous disease.

Who gets it?

It tends to appear in children between 3 months and five years old, but it can happen at any age. Some children are prone to croup and may get it several times.

In the Northern hemisphere, it is most common between October and March, but can occur at any time of the year.

What are the symptoms?

Croup is characterized by a brassy cough that sounds rather like a seal barking. Most children have what appears to be a mild cold for several days before one evening when the barking cough becomes evident. As the cough gets more frequent, the child may have stridor (a harsh, crowing noise made during inspiration).

Croup is typically much worse at night. Cool air or steam can briefly decrease the swelling in the larynx and improve the symptoms.

Is it contagious?

Croup caused by an infection is contagious. Croup caused by allergies or foreign bodies is not.

How long does it last?

Croup often lasts 5 or 6 nights, but the first night or two are usually the most severe. Rarely, croup can last for weeks. Croup that lasts longer than a week or that recurs frequently should be discussed again with your doctor to determine the cause.

How is it diagnosed?

Children with croup are usually diagnosed based on the history and physical exam. Sometimes a doctor will even identify croup by listening to a child cough over the phone. Occasionally other studies, such as x-rays, are needed.

How is it treated?

Most cases of croup can be safely managed at home, but you will want to call your physician for guidance, even in the middle of the night.

Acetaminophen can make the child more comfortable and lower any fever, lessening his or her respiratory needs. Avoid cough medicines especially in children under 6 years old unless you discuss them with your doctor first.

You may want your child to be seen. Steroid medicines can be very effective at promptly relieving the symptoms of croup. Medicated aerosol treatments, if necessary, are also powerful.

If your child is not responding to home treatment, or is struggling to breathe, has stridor at rest, retractions (tugging-in between the ribs with inspiration), dusky lips, drooling, or is very tired or agitated, she should be seen immediately. If you suspect a foreign body or an insect sting as the cause of croup, she should be also seen immediately. Some children with croup require hospitalization for a few days.

How can it be prevented?

Most causes of croup are spread by direct contact, droplet transmission, and by fomites. Careful hand washing and other appropriate precautions can decrease the spread of these viruses.

The diphtheria, Haemophilus influenzae (Hib), and measles vaccines protect children from the most dangerous forms of croup and infectious airway obstruction.

Related concepts:

Laryngotracheobronchitis, Infectious croup, Spasmodic croup.

Dr. Alan Greene

As a father of four himself, Dr. Greene has devoted himself to freely giving real answers to parents' real questions -- from questions about those all too common childhood conditions to those that address the most recent and rare pediatric illnesses. His answers combine cutting edge science, practical wisdom, warm empathy, and a deep respect for parents, children, and the environment. He is also an electrifying public speaker, and has personally touched many during his talks in North America, Europe, Asia, and the Middle East.

Dr. Greene is a graduate of Princeton University and the University of California at San Francisco. Upon completion of his pediatric residency program at Children's Hospital Medical Center of Northern California he served as Chief Resident. He entered primary care pediatrics in January 1993.

Dr. Greene is the Past President of The Organic Center and on the Board of Directors of Healthy Child Healthy World. He is a founding partner of the Collaborative on Health and the Environment. He also consults for the Environmental Working Group.

In 1995, he launched, cited by the AMA as “the pioneer physician Web site” on the Internet. His award-winning site has received over 80 million Unique Users from parents, concerned family members, students, and healthcare professionals. In addition to being the founder of, he is the Medical Director for HealthTap.

In 2010 Dr. Greene founded the WhiteOut Movement to change how babies in the United States are fed. In 2012 he founded TICC TOCC - Transitioning Immediate Cord Clamping To Optimal Cord Clamping. He is also the founder of KidGlyphs, a free iPhone app that provides a tool for young children to express themselves beyond their verbal skills while teaching them important language skills.

Dr. Greene is the Founding President of the Society for Participatory Medicine and has served as both President and Board Chair of Hi-Ethics (Health Internet Ethics. He is on the Board of Directors for Healthy Child Healthy World, The Lunchbox Project, and The Society for Participatory Medicine. He has also served as an advisor to URAC for both their inaugural and their updated health web site accreditation program. He is a founding member of the e-Patient Scholars Working Group, and a founding board member of the Center for Information Therapy.

Dr. Greene is a regular columnist for Parenting Magazine. He is also the Pediatric Expert for The People’s Pharmacy (as heard on NPR) and Healing Quest (seen on PBS stations). He was the original Pediatric Expert for both Yahoo! and iVillage.

Dr. Greene is the author of Feeding Baby Green (Wiley, 2009), Raising Baby Green (Wiley, 2007), From First Kicks to First Steps (McGraw-Hill, 2004), The Parent's Complete Guide to Ear Infections (People's Medical Society, 1997), and a co-author of The A.D.A.M. Illustrated Family Health Guide (A.D.A.M., Inc., 2004). He is the medical expert for three additional books, The Parent's Soup A-to-Z Guide to Your New Baby, (Contemporary Books, 1998) The Parent's Soup A-to-Z Guide to Your Toddler, (Contemporary Books, 1999), and The Mother of All Baby Books, (Hungry Minds, Inc., 2002).

Dr. Greene is a frequent keynote speaker at important events such as Health 2.0 2011 held in San Diego, CA, IFOAM 2008 (International Federation of Organic Agriculture Movements), held in Modena Italy, the first European Internet health conference, held in Maastricht, the first International eHealth Association Conference, held in Jeddah, and the largest e-Healthcare World Conference, held in Las Vegas, and the first Green Power Baby Shower, held in Hollywood. Dr. Greene also appears frequently on TV, radio, websites, and in newspapers and magazines around the world, including such venues as the TODAY Show, Good Morning America, Fox and Friends, The Dr. Oz Show, CNN, ABC, CBS, and NBC network news, NPR, The New York Times, The Wall Street Journal, USA Today, Time Magazine, Parade, Parenting, Child, Baby Talk, Working Mother, Better Home's & Gardens, and the Reader's Digest.

Dr. Greene loves to think about challenging ideas, he enjoys being where nothing manmade can be seen, and he wears green socks.

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