Why does croup cause cough?

Croup is usually caused by a viral infection affecting the upper airway. The tissues around the larynx and trachea can become swollen, particularly in young children whose airways are smaller. Air passing through this narrowed area creates the familiar seal-like cough; it may be more noticeable at night or when a child is upset. Cough is a very common presentation of Croup.

Some children also develop a high-pitched noise while breathing in, called stridor. A cough alone can occur with many illnesses, so the sound of breathing and the child's effort to breathe matter more than the cough label.

Keep your child calm and upright, offer frequent drinks, and check them regularly. Crying can make airway noise more pronounced. Use fever or pain medicine only as directed for your child's age and health needs. Do not use steam, as hot water can cause burns and it does not treat the airway swelling. A clinician may prescribe medicine that reduces swelling when appropriate.

Get urgent medical help if your child is struggling to breathe, has stridor while resting, is pulling in at the ribs or neck with breaths, looks blue or unusually pale, drools and cannot swallow, is very drowsy, or is difficult to wake. Seek same-day advice if symptoms are worsening, fluids are being refused, or you are concerned about their breathing.

Ask whether the breathing sounds are consistent with croup, whether treatment to reduce swelling is needed, and what changes should prompt urgent review. Mention any previous airway problems, medicines, allergies, or trouble drinking.