Acute laryngitis refers to hoarseness or loss of voice that appears suddenly after a night of singing and shouting, or being exposed to a lot of cigarette smoke. This condition usually improves when you avoid whatever has been irritating the throat (like cigarettes) and when you rest your voice. The common cold and influenza (the flu) are common causes of acute laryngitis, but it can also be a symptom of bronchitis, pneumonia, and measles. Hoarseness may also be part of an allergic reaction.
Chronic laryngitis lasts longer than a week and comes back over time. This condition can involve permanent changes in the lining of the throat. These changes could be due to repeated attacks of acute laryngitis like those sometimes experienced by professional singers, or happen because of repeated exposure to smoke, dust, dryness, or other irritants. Chronic laryngitis can also be caused by allergies and postnasal drip or gastroesophageal reflux disorder (GERD; when stomach acids rise up into the esophagus and cause burning).
Rarer causes of chronic laryngitis include cancer of the throat, noncancerous tumours on the vocal cords, and noncancerous wart-like lesions called papillomas that grow in the throat.