An 8-month-old has a cold and is making a noisy, rattly sound when breathing. After nasal suctioning the sound goes away. What was this?
Whistling Sound When Breathing Out (Wheezing)
Wheezing is a high-pitched whistling sound that happens when a child breathes out. It occurs because the small breathing tubes inside the lungs have become narrowed — by swelling, mucus, or tightening of the muscles around them. Air being pushed through these tighter tubes vibrates and creates the whistle, similar to the sound made when blowing through a pinched straw.
Hearing a whistling sound when your child breathes out can be worrying. This guide explains what wheezing sounds like, what causes it in babies and young children, and when to call your pediatrician.
- Clinical term: Wheezing
- Parents often search for: whistling sound when toddler breathes out, baby wheezing whistling sound chest, child makes whistling noise when breathing out, wheezing infant cold, high pitched whistle when baby exhales
Video demonstrating wheezing on breathing out
What does normal breathing sound like in babies and young children?
- Normal breathing is quiet or nearly silent when the baby is calm — parents may hear soft even airflow but no whistling, squeaking, or musical sounds from the chest.
- Babies make many normal noises — snorts, snuffles, and rattling from the nose and throat — caused by nasal congestion, not the lungs.
- Normal breathing in babies ranges from about 30 to 60 breaths per minute and is regular and effortless — the chest and belly rise and fall smoothly without visible strain.
- Noisy breathing from a stuffy nose is not wheezing — congestion sounds wet and rattly and comes from the nose, while true wheezing is a musical whistle from the chest during breathing out.
- A helpful test: if the noisy breathing clears when the nose is suctioned, it was likely nasal congestion.
- If the whistling continues after clearing the nose, it is more likely true wheezing from the lungs.
What causes wheezing in babies and young children?
- The two most common causes in children under six years old are bronchiolitis — a viral infection of the small airways, most common in babies under 12 months — and asthma, more common in toddlers and older children.
- Viral infections — especially RSV, rhinovirus, and influenza — cause swelling and extra mucus inside the small airways, narrowing them and creating the whistling sound.
- In children over one year old, wheezing can also be caused by a small object being inhaled — which blocks one airway and causes sudden one-sided wheezing.
- Wheezing that only happens during colds and goes away completely between illnesses is called episodic viral wheeze.
- Wheezing that also occurs between illnesses — during exercise, laughing, or at night — may suggest asthma.
- Less common causes include stomach acid irritating the airways, congenital airway abnormalities, and rarely heart conditions.
What does wheezing look and sound like — and how can parents recognize it?
- True wheezing is a continuous, high-pitched, musical whistling sound heard mainly when the child breathes out — it may be audible from across the room in moderate cases, or only heard by placing an ear close to the child's chest.
- Nasal congestion, stridor, and normal baby snuffles are not wheezing — wheezing specifically comes from the chest during exhaling.
- Along with the sound, parents may notice faster breathing, nostrils flaring, or skin pulling in between the ribs — these are signs of increased effort.
- The child may cough frequently in bursts and pause during feeding to catch their breath — difficulty finishing a normal feed is an important clue that breathing is harder than usual.
- Recording a short video with sound on a phone can help the pediatrician hear exactly what the child sounds like — especially since symptoms may change by the time of the office visit.
What can parents do at home when their child is wheezing?
- Stay calm and observe — note whether the wheezing is constant or comes and goes, whether it is getting better or worse, and whether the child is still feeding and producing wet diapers normally.
- Clear nasal congestion with a bulb syringe and use a cool-mist humidifier — this will not stop true wheezing but can improve comfort.
- Offer smaller more frequent feeds — a wheezing child may tire quickly during feeding, so shorter sessions with breaks can help maintain hydration.
- If the child has a known asthma condition and the pediatrician has provided a written action plan with a prescribed inhaler, follow that plan as directed.
- Do not use over-the-counter cough or cold products in young children — these are not recommended and can be harmful.
- Track the pattern — note when wheezing started, what seems to trigger it, and whether it is improving or worsening, so this can be shared with the pediatrician.
When should parents call the doctor or seek care?
- Call the pediatrician if wheezing is new and persistent, if the child is feeding less than half of normal amounts, or if wet diapers have decreased noticeably.
- Seek emergency care immediately if the child shows blue or gray color around the lips, tongue, or fingertips, or if the child is limp, unusually sleepy, or very difficult to wake.
- Seek urgent care if breathing rate is consistently fast and the child appears to be working hard with each breath — skin pulling in at the neck, ribs, or belly.
- A sudden onset of wheezing in a previously well toddler without cold symptoms should raise concern for a swallowed or inhaled foreign object — this warrants prompt medical evaluation.
- If the child has a known asthma condition and the prescribed inhaler is not providing relief within the expected time frame, contact the pediatrician or seek emergency care.
