The classic symptom of croup is a harsh, brassy cough that sounds like a seal's bark. This cough is often worse at night. And it usually occurs with hoarseness and loud, raspy breathing.
Other symptoms vary, depending on whether the illness is infectious croup or spasmodic croup.
Children with infectious croup often have a low-grade fever and mild cold symptoms before a cough begins. In many cases, the sick child also has a history of being exposed to a family member, friend or classmate with a cough, runny nose or other signs of a respiratory infection.
Most children with infectious croup are mildly ill and do not develop significant breathing problems.
Among the few who do develop more severe forms of the illness, symptoms can include:
Breathing faster than normal
Having difficulty breathing
An abnormal sucking in of the chest and abdominal muscles (retractions) as the child struggles to take a breath
Unusual restlessness or agitation
A bluish color of the skin, especially at the lips and fingernails
A child with spasmodic croup often looks fairly healthy before coughing starts. Episodes of cough and loud, raspy breathing generally start without warning. They typically occur in the middle of the night.
These symptoms often will pass if the child is carried into cool night air or taken into a steamy bathroom.
Symptoms from spasmodic croup usually improve within a few hours. However, it is common for the symptoms to reappear several nights in a row.