Stomach, heart, or ears to blame.

The common cough is almost as ubiquitous as the common cold, but its origins can be just as varied, even during the sniffly season. According to William Bria, a lung specialist at the University of Michigan Medical Center, it can be caused by almost any system in the body, including the stomach, the heart, and even the ear.

Impacted wax can stimulate a nerve in the ear canal which, in turn, brings on coughing. "While the problem is more common in children, we've seen it in adults, too. The solution is to dissolve the wax, flush it out, and you've cured the cough."

Problems of the stomach can trigger both coughing and shortness of breath. For example, in acid indigestion and heartburn, acid rising from the stomach can stimulate nerves in the esophagus and trigger a coughing reflex or an asthma attack. Congestive heart failure can bring on the same symptoms when the lungs fill with fluid...