Bronchiolitis: Symptoms, Causes, and Treatment

Bronchiolitis is one of those baby illnesses that can look like a plain old cold… right up until it doesn’t.
One day your little one is sniffly and cranky, and the next day they’re breathing fast, eating less, and making a tiny “whistling” sound you definitely didn’t order.
The good news: most cases of bronchiolitis are mild and get better with time and supportive care.
The tricky part: because it affects the smallest airways, symptoms can feel intense (especially for infants), and knowing when to watch at home vs. get urgent care matters.

This guide breaks down what bronchiolitis is, what causes it, the symptoms to look for, what treatments actually help,
what treatments usually don’t, and how to protect your household during respiratory virus season.
(Spoiler: the “best medicine” is often boring stuff like fluids, suction, and patience. Sorry. Science is not always flashy.)

What Is Bronchiolitis?

Bronchiolitis is a viral infection of the lower respiratory tract that causes inflammation and swelling in the bronchioles
(the tiniest airways in the lungs). When those small airways get irritated, they can narrow and fill with mucus.
That combination makes it harder for air to move in and outespecially when a baby’s lungs are already small and their nose is basically their favorite breathing device.

Bronchiolitis is most common in children under age 2, with many cases occurring in the first year of life.
It tends to show up more during colder months (when respiratory viruses throw their annual party).

Bronchiolitis vs. Bronchitis (They’re Not Twins)

People mix these up all the time:

• Bronchiolitis affects the smallest airways (bronchioles), mostly in infants and toddlers.
• Bronchitis affects the larger airways (bronchi) and is more common in older kids and adults.

What Causes Bronchiolitis?

Bronchiolitis is almost always caused by a virus. The most common culprit is RSV (respiratory syncytial virus),
but other viruses can do the same thing, including rhinovirus (the common cold), parainfluenza, influenza, and human metapneumovirus.

How It Spreads

Viruses that cause bronchiolitis spread through respiratory droplets and contaminated hands/surfaces.
Translation: coughing, sneezing, shared toys, shared spoons, shared anything, and that one relative who “isn’t that sick.”

Who’s More Likely to Get a More Severe Case?

Most children recover at home, but the risk of severe illness is higher in babies who are:

• Very young (especially under 2–3 months)
• Born prematurely
• Living with chronic lung disease or significant heart disease
• Immunocompromised
• Having trouble feeding/hydrating because of the illness

Bronchiolitis Symptoms (What You’ll Notice First)

Bronchiolitis often starts like a basic upper respiratory infection. Early symptoms can include:

• Runny or stuffy nose
• Mild fever (not always)
• Cough
• Decreased appetite or drinking less
• Fussiness or low energy

Over the next couple of days, symptoms may move “down” into the lungs and become more noticeable:

• Wheezing (a high-pitched whistling sound, often when breathing out)
• Fast breathing
• Increased work of breathing (belly breathing, chest pulling in between ribs, flaring nostrils)
• Trouble feeding (because breathing and eating at the same time is hardeven for adults)
• Dehydration signs (fewer wet diapers, dry mouth, less tears)

A Quick “Real Life” Example

A typical pattern: a 6-month-old starts with a runny nose and cough on Monday, seems worse by Wednesday (more coughing, faster breathing),
and hits peak intensity around day 3–5. After that, the breathing gradually improves, while the cough may linger longer.

When to Seek Urgent Care

Trust your instinctsif your child looks like they’re struggling, it’s okay to get evaluated.
Call your pediatrician urgently or seek emergency care if you notice:

• Struggling for each breath, grunting, or pauses in breathing
• Blue/gray lips or face
• Severe chest retractions (skin pulling in around ribs/neck)
• Very fast breathing that doesn’t settle
• Unable to keep fluids down or refusing feeds + fewer wet diapers
• Extreme sleepiness, limpness, or difficulty waking
• Any infant who is very young (especially < 3 months) with significant symptoms

If you’re ever unsure, it’s better to call. Nobody gets a trophy for “waiting it out” with a struggling baby.

How Bronchiolitis Is Diagnosed

Bronchiolitis is usually diagnosed clinically, meaning a healthcare provider listens to the history and examines your child
(breathing rate, effort, wheezing/crackles, hydration, and oxygen levels).

Do Kids Need Tests?

Often, no. Many cases don’t need blood tests, chest X-rays, or viral testing. Providers may check oxygen saturation with a pulse oximeter,
and testing decisions are typically based on severity, age, and clinical judgment.

Bronchiolitis Treatment: What Actually Helps

There isn’t a magic “cure” that makes bronchiolitis disappear overnight. Since it’s usually viral, treatment focuses on
supportive care: helping your child breathe more comfortably, stay hydrated, and get through the worst days safely.

At-Home Care (Most Mild Cases)

• Nasal saline + gentle suction: Clearing a stuffy nose can make breathing and feeding easier.
  Many parents find it most helpful before feeds and sleep.
• Fluids: Offer smaller amounts more often. Hydration is a big deal in infants.
• Fever comfort: Use fever reducers only as directed by your child’s clinician (and never give aspirin to kids).
• Humidified air: A cool-mist humidifier may help comfort (clean it regularly so it doesn’t become a science experiment).
• Rest: Your child’s body is doing repair work.
• Smoke-free environment: Avoid tobacco smoke and vaping aerosolsthey can worsen symptoms.

Hospital Treatment (For Moderate to Severe Cases)

A child may be hospitalized if they need extra breathing support, can’t maintain hydration, or need close monitoring.
Hospital care may include:

• Oxygen if oxygen saturation is low or work of breathing is high
• Hydration support (oral, NG tube feeds, or IV fluids depending on the situation)
• Suctioning to relieve nasal obstruction
• Respiratory support such as high-flow nasal cannula; in severe cases, more advanced support may be needed

Treatments That Usually Don’t Help (And Why)

This is where bronchiolitis is famously unimpressed by many common “respiratory” medications:

• Antibiotics: Not helpful for viral bronchiolitis (unless there’s evidence of a secondary bacterial infection).
• Albuterol/bronchodilators: Generally not recommended for routine bronchiolitis because most infants don’t get consistent benefit.
  (Your clinician may consider exceptions based on individual factors, but it’s not standard.)
• Steroids: Not routinely recommended for typical bronchiolitis.
• Cough/cold medicines in young children: Often not recommended and can cause side effects without proven benefit.

In some hospitalized settings, nebulized hypertonic saline may be considered for certain patients,
but it’s not a universal “fix,” and practices vary.

How Long Does Bronchiolitis Last?

Many children improve over about 1–2 weeks, but the timeline isn’t always linear.
Symptoms often worsen for a few days before they get better. The cough can hang around longer than the dramatic breathing phase.

What “Getting Better” Can Look Like

• Breathing rate slows down
• Less belly breathing/retractions
• Feeding improves
• Sleep becomes less interrupted by coughing

Possible Complications

Most kids recover without long-term problems, but bronchiolitis can lead to complications in some cases:

• Dehydration (from poor feeding + faster breathing)
• Low oxygen levels
• Apnea in very young infants
• Hospitalization for breathing support
• Recurrent wheezing in some children later on (the relationship is complexbronchiolitis can be an early marker of airway sensitivity in some kids)

Prevention: How to Lower the Odds (and the Drama)

You can’t bubble-wrap a baby (and even if you could, they’d probably lick the bubble wrap), but prevention helps:

• Handwashing and sanitizing before holding babies
• Avoid close contact with people who are sick
• Clean high-touch surfaces (toys, doorknobs, phones)
• Limit smoke exposure in the home and car
• Breastfeeding can offer immune support (when possible)

RSV Protection Options (Important for Infants)

Because RSV is a leading cause of bronchiolitis, medical prevention options may be available depending on your child’s age,
risk factors, and the time of year. In the U.S., current guidance includes protection for many infants through either:
maternal RSV vaccination during pregnancy (timed seasonally) or an infant monoclonal antibody
given during RSV season. Some higher-risk toddlers may also qualify for protection in a second RSV season.
Ask your pediatrician what’s recommended for your baby in your area.

FAQ

Is bronchiolitis contagious?

The viruses that cause bronchiolitis are contagious. Bronchiolitis itself is the lung responseso you’re really spreading the virus.

Can adults get bronchiolitis?

The term “bronchiolitis” is mostly used for infants and young children.
Adults can get lower respiratory infections too, but the diagnosis and patterns differ.

Should my child stay away from daycare?

If your child has fever, significant coughing, trouble breathing, or can’t participate comfortably, staying home is usually bestfor recovery and to reduce spread.
Follow your daycare’s illness policy and your clinician’s advice.

Conclusion

Bronchiolitis is common, stressful, and usually temporary. It typically starts like a cold and can escalate into wheezing,
fast breathing, and feeding strugglesespecially in babies. Most treatment is supportive: clearing the nose, keeping fluids going,
monitoring breathing, and getting medical care quickly if symptoms become severe. Knowing the red flags (breathing difficulty, dehydration, color change, extreme lethargy)
helps you act confidently. And during RSV season, preventive options may reduce the risk of severe disease for many infants.

Experiences From the Real World (What Families Often Notice)

If you’ve ever tried to “just relax” while your baby makes a weird breathing noise at 2:00 a.m., you already know bronchiolitis isn’t just a diagnosisit’s an experience.
Here are a few common patterns families describe, gathered from the typical day-to-day reality of caring for infants with bronchiolitis. (Not medical advicejust the
kind of “oh wow, that’s exactly what happened to us” stuff that makes you feel less alone.)

1) The Day-3 Surprise. Many parents say the first day looks like a standard cold: runny nose, mild cough, cranky mood.
Thenoften around day 3 to 5things peak. The cough sounds harsher, breathing speeds up, and feeding gets harder.
It can feel like the illness is “suddenly worse,” even though it’s a classic bronchiolitis timeline. Families often report that once they learn this pattern,
they stop blaming themselves for “missing something earlier” and start focusing on monitoring and comfort.

2) Feeding becomes the main event. A baby with bronchiolitis may want to eat less, take shorter feeds, or get frustrated because they can’t breathe well through a stuffy nose.
Parents often discover that offering smaller amounts more often works better than trying to force a normal feeding schedule.
For bottle-fed babies, pacing can help. For breastfed babies, shorter, more frequent nursing sessions can be easier. Many caregivers start using “wet diapers” as their calm,
practical scoreboardbecause hydration is one of the clearest signals that things are still okay.

3) Suctioning: awkward at first, helpful later. Families often describe nasal saline and gentle suction as a game-changerafter the learning curve.
The first attempt can feel like you’re wrestling an octopus who’s offended you touched their nose. But once parents get the hang of it,
they tend to use suction right before feeds and sleep. The goal isn’t to make the nose “perfectly clear” (babies have opinions); it’s to make breathing easier for the next activity.
People also mention that gentle suction mattersoverdoing it can irritate the nose and make things worse.

4) The “Do we go in?” debate. One of the most common caregiver experiences is uncertainty: “Is this normal sick… or urgent sick?”
Families often find it helpful to watch for concrete signs: persistent retractions, very fast breathing, pauses in breathing, color changes, or fewer wet diapers.
Many parents describe calling the pediatrician hotline for reassurance and guidance, especially overnight. The emotional takeaway is consistent:
it’s better to be evaluated and told “you’re doing great” than to wait while you’re genuinely worried.

5) If hospitalization happens, it’s usually about supportnot ‘stronger medicine.’ Parents are often surprised to learn that in the hospital,
the big tools are oxygen, fluids, suctioning, and monitoring. Families describe relief when oxygen or high-flow support reduces the work of breathing,
and they often say the scariest part was the uncertainty before getting help. Once the baby is supported, the rhythm becomes: rest, breathing support, hydration,
and waiting for the virus to run its course. It’s not glamorous, but it’s effective.

6) Recovery can be “two steps forward, one step back.” Even after the worst passes, many families report a lingering cough,
uneven sleep, and days that seem better followed by a slightly rougher night. That’s common with many respiratory viruses.
Parents often say it helps to track overall trends (Is breathing easier than two days ago? Is intake improving?) rather than judging recovery hour-by-hour.

If there’s one consistent theme, it’s this: bronchiolitis is usually temporary, but it can feel intense while you’re in it.
Clear return-to-care rules, a plan for hydration, and support from a clinician can turn the chaos into something manageable.