Dr. Paul G. Donohue responds to a reader's question about ongoing hoarseness and what might cause such a problem. Dr. Donohue says that hoarseness that lasts more than two weeks is a signal that a doctor should be consulted. The problem, he explains, may be due to a viral infection of the voice box, or even cancer. A little-known cause may be gastroesophageal reflux disease (GERD). Stomach acid may back up into the throat and irritate the voice box causing a raspy, irritated throat. Dr. Donohue...