Plastic bronchitis is an uncommon condition with a poor prognosis characterized by an obstructive respiratory pattern due to airway blockage by the presence of bronchial casts. Therefore, it is important to include it in the differential diagnosis of respiratory distress, particularly in patients with underlying pathologies predisposing to this condition. The etiology is multifactorial, but typically occurs in children with congenital heart disease, particularly post‐Fontan procedure. The treatment is based on improving the underlying condition, which can be challenging in this type of patients.