Updated April 27, 2026

Many parents spend the first few years of their child’s life closely monitoring their breathing and listening for new or unusual sounds. These sounds may include wheezing, congestion, stridor, or rough breathing that can be difficult to interpret for both parents and care teams.

"It's important for parents to realize that breathing noises mean different things and these sounds sometimes point to a serious health issue," says pediatric otolaryngologist Jonathan Walsh, M.D., who explains how to tell what the differences in your child's breathing can mean and what to do about them.

How can I tell the difference between wheezing, stridor and stertor?

Changes in breathing sounds can be scary for parents and family, yet noisy breathing is common among infants and toddlers.

"Children's airways are softer and narrower than adults', so they're more prone to make loud breathing noises," Walsh says. "But not all noisy breathing is equally concerning—and some of these sounds will resolve on their own over time."

Here's how the distinct noises break down:

Wheezing

In general, a wheeze is a high-pitched musical sound coming from the small airways of the lungs that happens with breathing out (exhalation), though it can occasionally happen on the inhale. It occurs when the lower airway is partly blocked or narrowed. "To tell if the sound you're hearing is a wheeze or not, you have to listen to the lungs," Walsh says.

The most common causes of wheezing are:

• asthma
• reactive airway disease, a condition often triggered by a viral infection

"Wheezing can also happen when a child has a virus, asthma, or if they choke on something that makes its way to the lungs," explains Walsh.

Stridor

Less musical sounding than a wheeze, stridor is a high-pitched, turbulent sound caused by narrowing of the airway that can happen when a child inhales or exhales. Stridor usually indicates an obstruction or narrowing in the upper airway, outside of the chest cavity. "Stridor in infants, particularly without any associated illness, should always be checked out by a physician," Walsh says.

A number of conditions can block or narrow the upper airway and cause stridor. The most common is a viral infection called croup. Other causes include:

• swallowing a small object that gets lodged in the airway
• upper respiratory infection
• inflammation
• cysts or masses
• vocal cord problems
• scarring
• laryngomalacia
• tracheobronchomalacia
• certain congenital heart conditions

Stertor

While stertor is less well-known than either wheezing or stridor, it's also a lot more common. "The sound that a nasally congested child makes is stertor," Walsh says. "It's almost like a snoring sound that indicates obstruction in the mouth and nose."

Stertor can happen with a common cold. It can also indicate adenoid enlargement from allergies or flu. In rare cases, stertor may result from a structural abnormality in the back of the nasal cavity.

When should you see a specialist for a child's noisy breathing?

Figuring out the cause of noisy breathing isn't clear-cut. Parents and primary care doctors may not be able to tell the difference between wheezing, stridor and stertor in an infant or young child by exam alone. Diagnosing the problem often requires a thorough evaluation of the lungs and upper airways.

"Most of the time, noisy breathing is not dangerous and will resolve without treatment, Walsh says. "If noisy breathing doesn't quiet down after an illness has passed, if it worsens with increasing respiratory distress, or if it goes away and comes back, the child should be evaluated by a specialist."

The specialist may perform a variety of tests to determine the source of noisy breathing. A few of the most common:

• Laryngoscopy, an in-office procedure to examine the throat and upper airway
• Bronchoscopy, a procedure that requires anesthesia but provides a clearer view of the entire airway
• Chest x-ray, to check for signs of blockage
• Pulmonary function test, to evaluate the lower airways
• Swallow study, to determine whether the airway is compressed or functioning normally

What are the treatment options for children with noisy breathing?

Treatment for noisy breathing depends on the underlying cause. A child who is sick and wheezing may be less concerning than a child who has wheezing from both lungs and without any noticeable illness.

Successful treatment often relies on having a team of pediatric professionals, which can include:

• an ear, nose, and throat specialist
• a pulmonologist
• a gastroenterologist
• a cardiologist

Doctors may take a "wait-and-see" approach, while providing children with supportive care. Children may require use of a nebulizer, a device that turns liquid medicine into a mist that can be inhaled, to help them breathe easier. Severe cases can require immediate surgery.

Questions your doctor will ask that will inform your child's treatment include:

• When did you first notice the condition?
• Has your child been ill recently?
• Did your child put a foreign object in his mouth?
• Does your child have trouble swallowing?
• Is your child struggling to breathe?
• Was your child born prematurely or spent time in the neonatal ICU?
• Has your child ever had a breathing tube placed (intubated)?

"If your child is struggling to breathe or showing signs of labored breathing, such as bluish hue on the lips, skin or body or the chest collapsing inward, call 9-1-1 or take your child to the nearest emergency room," notes Walsh.

Medically reviewed by Jonathan Walsh, MD