Approximately 6% of elderly patients present to primary care offices with hypertension and upper respiratory infection. Elderly people develop an acquired immunity to many rhinoviruses, making them less susceptible than younger people to the common cold. But because of the decreased vigor of their immune systems, they are less able to fight infection, particularly secondary bacterial infections. Upper respiratory infections require close monitoring in elderly patients to detect secondary infections and other complications. Most published research on respiratory symptom treatment is not limited to elderly subjects.