orthopnea: form of dyspnea in which the person can breathe comfortably only when standing or sitting erect; associated with asthma and emphysema and angina pectoris
dyspnea: difficult or labored respiration
pentoxifylline: a drug (trade name Trental) used to treat claudication; believed to increase the flexibility of red blood cells so they can flow through the blood vessels to the legs and feet