Central hypoventilation syndrome (CHS) is a rare disorder that affects breathing. It is also known as Ondine's curse or congenital central alveolar hypoventilation syndrome (CCAHS). Some synonyms for CHS include autonomic or respiratory dysregulation, hypoventilation, and central sleep apnea. Other terms that may be used include respiratory failure, nocturnal hypoventilation, and Cheyne-Stokes respiration. CHS is often characterized by abnormal breathing patterns that can lead to respiratory failure if left untreated. Treatment may include supportive measures such as oxygen therapy and/or mechanical ventilation, as well as medications to manage symptoms. With proper management, people with CHS can live full and healthy lives.