What is the term for difficulty breathing while lying down?

The term for difficulty breathing while lying down is orthopnea. This condition typically occurs when a person is unable to breathe comfortably in a supine position and often relieves itself when standing or sitting up. Orthopnea is commonly associated with heart failure, where lying flat increases venous return to the heart, exacerbating pulmonary congestion and leading to shortness of breath.

In contrast, dyspnea refers to the general sensation of breathlessness or difficulty breathing, which can occur in various positions and isn't limited to lying down. Asthma is a condition characterized by chronic inflammation of the airways, leading to wheezing, coughing, and shortness of breath but isn't specifically related to body position. Apnea refers to a temporary cessation of breathing, which is fundamentally different from the experience of difficulty breathing.