While hiccups are a common annoyance that usually go away after a few hours, chronic hiccups may last for days, and in some rare cases (approx. 1 case per 100,000 subjects), they can last for years.
Chronic hiccups causes
The most prominenet known cause of chronic hiccups is esophagitis due to gastroesohpageal reflux. Esophagitis is a general term for any inflammation, irritation, or swelling of the esophagus, the tube that leads from the back of the mouth to the stomach. Gastroesophageal reflux disease (GERD) is a condition in which the stomach contents (food or liquid) leak backwards from the stomach into the esophagus (the tube from the mouth to the stomach). This action can irritate the esophagus, causing heartburn and other symptoms. Surgery, tumors, and lesions may also cause persistent hiccups.
Persistent hiccups can sometimes be an indication of the presence of
another medical problem. Chronic hiccups may be a symptom for some of
Alcoholism, bowel diseases, disorders of the stomach or esophagus, heart failure, pleurisy of the diaphragm, pneumonia, and uremia. Hiccups may also be associated with bladder irritation, hepatitis, liver cancer, pancreatitis, or pregnancy.
Chronic Hiccups Treatment (we recommend trying #1 first, if it doesn't work, go onto #2, and so on):
If these home remedies do not work and your hiccups persist for more than a few days, DO NOT neglect visiting the doctor!
Here's an interesting article on chronic hiccups from the New York
A Horrific Case of Hiccpus, A Novel Treatment
References (for chronic hiccups):
Article: Chronic hiccup by Professor Jean Cabane
National Institues of Health (US Department of Health & Human Services)