A sudden “barking” cough in the middle of the night can feel like an alarm bell. Your child sounds hoarse, breathing turns noisy, and seconds later you are watching every breath. Croup often looks dramatic, but most episodes improve with the right calm, positioning, and (when needed) targeted medication that reduces swelling just below the vocal cords. The challenge is triage: spotting typical croup signs, easing your child’s breathing, and recognizing the few situations that need urgent care.

Recognizing croup: the signs parents notice first

The cold phase (often the day before)

Croup commonly starts like a standard viral upper respiratory infection: runny nose, mild sore throat, low fever, and a cough that still sounds “normal.” Then the larynx (voice box) becomes inflamed, the subglottic area (just under the vocal cords) puffs up, and the sound changes.

The classic trio: barking cough, hoarse voice, stridor

Parents describe croup as:

A barking cough (seal-like, dry, rough)
Hoarseness (the voice may sound weak or scratchy)
Stridor (a high-pitched, harsh noise on breathing in)

You might wonder: “Why does it get louder when my child cries?” Because agitation increases airflow speed and turbulence through a narrowed upper airway. Calm truly matters.

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Breathing effort: noise is not everything

With croup, the intensity of stridor is important, but the work of breathing is even more informative. Watch for:

Retractions (skin pulling in between ribs, under ribs, or above the collarbones)
Nasal flaring
Faster breathing than usual
Head bobbing, difficulty staying lying down, or a preference for sitting upright

Stridor at rest (when your child is calm) is a red flag and deserves prompt medical assessment.

Fever, fatigue, and “behavior clues”

A low-grade fever often accompanies viral croup. Higher fever can occur with influenza and some other viruses.

What raises concern is the combination: fever plus a child who looks very unwell, drools, refuses to swallow, or seems to struggle for air.

Behavior changes can also guide you:

A very agitated child can look worse quickly.
A child who becomes unusually quiet, drowsy, or exhausted may have more severe airway narrowing.

Drinking less: the part that sneaks up

When breathing is hard work, drinking becomes a chore. During croup, watch for:

Shorter feeds or frequent pauses
Vomiting after coughing bouts
Fewer wet diapers, dark urine, dry mouth, no tears

Hydration is not a “detail.” It influences recovery and helps you judge how well your child is coping.

What croup is (and why nights can feel brutal)

Croup is usually a viral inflammation of the upper airway, often called laryngotracheitis. The narrowest point in many young children is the subglottic area, even mild edema there can sharply reduce airflow.

Why nighttime? Several small factors stack up:

Lying down can worsen the sensation of blockage
Dry heated air irritates mucosa
Tired children cry more easily (and crying amplifies stridor)

Most croup episodes occur between 6 months and 3 years, and are uncommon after age 5 because the airway diameter increases.

Causes of croup and factors that can make it flare

Viruses: the usual starting point

The leading cause of croup is parainfluenza virus. Other viruses can do the same job: RSV, rhinovirus, influenza, adenovirus, and SARS-CoV-2. The immune response triggers inflammation and swelling, especially under the vocal cords, producing the bark and stridor.

Contagion at home or daycare

Croup is a clinical syndrome, the viruses behind it spread via droplets, close contact, and hands/surfaces. The “cold-like” phase is often when children are most contagious.

Irritants and dry air

During croup, the airway lining is sensitive. Tobacco smoke (even if “not directly near the child”), strong fragrances, pollution, and very dry indoor air can make nights noisier.

Recurrent episodes: reflux, allergy background, airway sensitivity

If croup returns repeatedly, clinicians may think about contributing factors:

Gastroesophageal reflux (GERD) irritating the larynx (clues: cough when lying down, discomfort after feeds, hoarseness that lingers)
Allergic rhinitis maintaining chronic inflammation (itchy eyes, sneezing, clear nasal discharge, seasonal pattern)
Environmental irritants
A naturally narrower subglottic airway

This does not mean something “serious” is automatically present, it means patterns are worth discussing.

Croup severity: mild, moderate, severe (how it tends to look)

Mild croup: barking cough, comfortable breathing, stridor only when crying or active
Moderate croup: stridor when calm, visible retractions, reduced drinking
Severe croup: persistent stridor at rest, marked retractions, agitation that may shift to fatigue, difficulty speaking/crying, poor intake

If you are hesitating between “moderate” and “severe,” the safest move is medical assessment.

Conditions that can mimic croup (and when to think beyond it)

Not every noisy breathing episode is croup.

Bronchiolitis: lower airway disease, more wheeze (often on breathing out), crackles, and feeding difficulty in young infants
Asthma/reactive airway disease: wheeze and prolonged exhalation, bronchodilators help (unlike typical croup)
Pertussis (whooping cough): long coughing fits, post-tussive vomiting, illness lasting weeks

Urgent evaluation is needed if symptoms suggest:

Epiglottitis: high fever, drooling, trouble swallowing, very ill appearance
Bacterial tracheitis: toxic look, high fever, worsening distress despite standard croup therapy
Foreign body aspiration: very sudden onset during eating/play
Anaphylaxis: hives, facial/lip swelling, vomiting, rapid airway swelling

How clinicians diagnose croup

Diagnosis of croup is usually clinical: history, listening for stridor, observing retractions, checking hydration, and often pulse oximetry (oxygen saturation). Imaging or viral tests are reserved for unusual, severe, or prolonged cases, or when another diagnosis is suspected.

Home care for croup: practical steps that often help

1) Calm and upright positioning

Hold your child upright. Dim lights. Use a soft voice. In croup, panic spreads quickly, yet calm can reduce stridor.

2) Fluids in small, frequent offers

Offer frequent sips (water, milk, oral rehydration solution). Popsicles can be useful for toddlers. If the nose is blocked, saline drops/spray and gentle suction can make feeding easier.

3) Humidification and steam: comfort, with safety

A cool-mist humidifier may help comfort in dry rooms. Clean it carefully to avoid mold.

Hot steam “setups” risk burns and are not a safe overnight strategy.

4) Cool air: a short trial

Some families see brief improvement by stepping into cool night air for a few minutes (warmly dressed, supervised). If croup stridor at rest persists, do not delay medical care.

What to avoid

Over-the-counter cough syrups for young children (limited benefit, possible harm)
Smoke exposure and strong fragrances
Essential oils/menthol rubs in infants or used close to the nose (can irritate)

Medical treatment for croup: what may be offered

Corticosteroids (often dexamethasone)

A single dose of dexamethasone is widely used for croup because it reduces upper-airway inflammation. The effect is not instant, improvement often appears over a few hours and can reduce the need for further care.

Some services use prednisolone depending on local protocols and availability.

Nebulized epinephrine (adrenaline)

For moderate-to-severe croup, nebulized epinephrine can rapidly reduce swelling. Because the effect can wear off, monitoring is needed afterward to ensure stridor does not rebound.

Oxygen and hydration support

If oxygen saturation is low, supplemental oxygen is provided. If drinking is too difficult, clinicians may support hydration and observe until breathing eases.

Antibiotics: usually not

Typical croup is viral, so antibiotics do not help. They are used only when bacterial complications are suspected (for example, bacterial tracheitis).

When to get medical advice – and when to seek emergency care

Contact a clinician the same day if

Stridor appears easily or lingers
Retractions are visible
Drinking drops or dehydration signs appear
Your child is under 6 months, was born very prematurely, or has chronic airway/heart/lung conditions
Symptoms worsen or do not improve over 24-48 hours

Seek emergency care now if you see

Stridor at rest or clearly labored breathing
Blue/gray lips or face
Pauses in breathing, fainting, or a concerning episode
Drooling or trouble swallowing
Severe exhaustion, unusual sleepiness, or inability to drink

While you are getting help: keep your child close, upright or semi-upright, and focus on calm. It can make breathing easier while you wait.

How long croup lasts

Most croup follows a familiar pattern: cold symptoms first, then the bark and stridor peak over 1-3 nights, with gradual improvement over several days. The bark often eases within about 48 hours, a regular cough may linger 1-2 weeks.

Return to daycare/school is usually reasonable once fever has resolved and your child can drink, sleep, and participate comfortably.

Key takeaways

Croup is usually a viral upper-airway illness with swelling below the vocal cords, nights often feel worse.
Barking cough, hoarseness, and stridor are typical, stridor at rest and visible retractions need prompt assessment.
Calm, upright positioning and frequent fluids support recovery, avoid smoke and irritating fragrances.
Dexamethasone is commonly used, nebulized epinephrine is reserved for more severe croup with monitoring.
If you are worried, resources and professionals can guide you, and you can download the Heloa app for personalized tips and free child health questionnaires.

Questions Parents Ask

Can adults catch croup from a child?

Croup itself is a syndrome (barking cough/stridor) most common in young children because their airways are smaller. The viruses that cause it (like parainfluenza, RSV, influenza) can spread to adults, so parents may catch the same virus and feel like a regular cold, sore throat, or hoarseness. Rassurez-vous: adults rarely develop true croup-like breathing noise. Handwashing, tissues, and cleaning shared surfaces help reduce spread at home.

Is croup contagious, and when can my child go back to daycare?

Yes—because it’s usually viral, it’s generally contagious during the cold-like phase and early days of coughing. Many parents worry about the “night bark,” but contagiousness is more about the underlying virus than the sound. Returning to daycare is usually reasonable once your child has no fever, can drink and sleep comfortably, and has enough energy for normal activities. If the cough is improving but still present, that’s often okay.

Why does my child keep getting croup?

Recurrent croup can happen, and it doesn’t automatically mean something serious. Some children simply have a more sensitive upper airway. In other cases, triggers like reflux (GERD), allergies, frequent viral exposure (daycare), or irritants (smoke, strong fragrances, very dry air) may contribute. If episodes are frequent, severe, or happening outside the usual age range, a clinician can help explore patterns and reassurance options.

Croup in children: symptoms, causes, and treatment