Acute viral bronchiolitis in babies and young children

It begins when a virus inflames the smallest breathing tubes and increases mucus. Babies can tire while breathing or feeding because their airways are narrow. Antibiotics do not treat the virus.

Bronchiolitis often presents first with a blocked or runny nose, followed by cough, faster breathing, wheezing or crackly sounds. Fever can occur. Feeding may take longer, and a baby may drink less because coordinating sucking, swallowing and breathing becomes harder.

A clinician assesses breathing effort, alertness, hydration and oxygen level. Wheezing alone does not show how unwell a child is; chest pulling, pauses in breathing, colour change and poor feeding are more concerning signs.

Offer smaller feeds more often and keep the child upright while awake and supervised. Saline nose drops and gentle clearing of nasal mucus before feeds may help. Keep the home free from tobacco smoke and check the child regularly, including during the night.

Use fever medicine only if it is suitable for the child's age and follow the product or clinician instructions. Cough medicines are not suitable for babies. Nebuliser treatment is not routinely helpful for straightforward viral bronchiolitis, although a clinician may consider inhaled treatment when another airway problem is suspected.

Call emergency services if the child has pauses in breathing, blue or grey lips, severe chest pulling, grunting, is floppy or cannot be woken normally. These signs indicate that breathing or oxygen delivery may be seriously affected.

Seek prompt medical review if breathing is becoming harder, feeds are much smaller than usual, nappies are noticeably drier, the mouth is dry, or the child is increasingly sleepy or irritable. Very young babies and children with heart, lung or immune problems should be assessed early when symptoms develop.

Ask how to judge breathing effort, what feeding amount or urine change should prompt reassessment, whether any medicine is appropriate, and how underlying health conditions affect the plan for monitoring at home.