The cough sounds tight, metallic and like a barking seal. The baby's voice or cry is usually hoarse. A harsh, raspy, vibrating sound is heard when the child breathes in. The high pitched noise is called stridor. Stridor occurs, as the opening between the vocal cords becomes narrower.
Stridor is usually only present when crying or coughing.
As the croup gets worse, stridor also occurs when the child is sleeping or relaxed. Because croup is a viral infection, antibiotics have no effect on the condition unless a secondary infection develops such as an Upper Respiratory Infection. Croup usually lasts 5 to 6 days and generally gets worse at night. During this time, it can change from mild to severe many times. Croup is very common in the winter months.