DefinitionHyperventilation is rapid or deep breathing that can occur with anxiety or panic. It is also called overbreathing, and may leave you feeling breathless.See also: Rapid shallow breathingAlternative NamesRapid deep breathing; Breathing - rapid and deep; Overbreathing; Fast deep breathing; Respiratory rate - rapid and deepConsiderationsWhen you breathe, you inhale oxygen and exhale carbon dioxide. Excessive breathing leads to low levels of carbon dioxide in your blood. This causes many of the symptoms you may feel if you hyperventilate.Feeling very anxious or having a panic attack are the usual reasons that you may hyperventilate. However, rapid breathing may be a symptom of a disease, such as:BleedingHeart or lung disorderInfectionYour doctor will determine the cause of your hyperv