A hiccup is an involuntary spasmodic contraction of the muscle at the base of the lungs (diaphragm) followed by the rapid closure of the vocal cords. Usually, hiccups last for a few hours or, occasionally, a day or two. However, chronic hiccups are ones that continue for an extended period of time. Episodes that last for more than two days and less than a month are sometimes called persistent hiccups. On rare occasions, hiccups persist even longer than a month or recur frequently over an extended period of time. The longest recorded episode of these chronic hiccups lasted 60 years.
Sometimes, although not always, hiccups that persist may indicate the presence of another medical problem. Some illnesses for which continuing hiccups may be a symptom include: pleurisy of the diaphragm, pneumonia, uremia, alcoholism, disorders of the stomach or esophagus, and bowel diseases. Hiccups may also be associated with pancreatitis, pregnancy, bladder irritation, liver cancer or hepatitis. Surgery, tumors, and lesions may also cause persistent hiccups.
Hiccups are unmistakable, and rarely taken for anything else. They often start for no apparent reason, and usually go away on their own in a few minutes. Of concern is the period of time required for an episode to run its course. Hiccups that persist over a period of time may cause exhaustion and weight loss from lack of sleep and the interruption of normal eating patterns.
The cause of hiccups often is not known, but some of the triggers sometimes thought to cause them include the following: spicy foods, hot liquids, any disease or illness that irritates the nerves that control the diaphragm.
The hiccup reflex involves the synchronized action of the diaphragm, the muscles that open and close the windpipe (trachea), and the nerves that act upon these muscles. Within the spinal cord, the “hiccup center” seems to be located somewhere between the cervical vertebrae numbered C3 and C5. There, nerve fibers from the brain monitor the activity and signal the contraction of the nerve (phrenic nerve) that permits exhalation.
If any of the nerves in this cycle is irritated for whatever reason(s), the diaphragm may contract involuntarily (spasm) and air is drawn into the lungs. This triggers the trachea to close, generating the typical hiccup sound.
The list of conditions that may lead to intractable hiccups is very long and may require long periods of time to isolate and identify. These include but are not limited to: brain lesions, tumors, intestinal diseases, liver or kidney disorders or uremic poisoning. Chronic hiccups may be caused by surgery or the drugs used during surgery. In some cases, a cause is not identified.
Hiccups affect males more often than females. Hiccups occur in practically every human being, but chronic hiccups are very rare.
The diagnosis of chronic hiccups may be obvious, but blood, imaging, and other laboratory studies may be used to determine the underlying cause.
Treatment of intractable hiccups often involves drug therapy with chlorpromazine (Thorazine), frequently prescribed. Among other medications used are haloperidol, and metoclopramide. If the hiccups occur during anaesthesia or surgery, the treatment is usually ephedrine or ketamine. Hypnosis has been used in some patients, as well as acupuncture. Surgical procedures such as injections into the phrenic nerve, or severing the phrenic nerve in the neck, have been used in cases where all other therapies have failed.
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Studies suggest that the drug amitriptyline may be a possible treatment option for chronic hiccups. More research is needed to determine the safety and effectiveness of this drug for treating hiccups.
Researchers in Italy have studied the use of the drug gabapentin (Neurontin) to treat people with chronic hiccups. Additional study is needed to determine the long-term safety and effectivenees of this drug.
Beers MH, Berkow R., eds. The Merck Manual, 17th ed. Whitehouse Station, NJ: Merck Research Laboratories; 1999:240.
Berkow R., ed. The Merck Manual-Home Edition.2nd ed. Whitehouse Station, NJ: Merck Research Laboratories; 2003:545.
Larson DE. ed. Mayo Clinic Family Health Book. New York, NY: William Morrow and Company, Inc; 1996:745.
Bennett JC, Plum F, eds. Cecil Textbook of Medicine. 20th ed. W.B. Saunders Co., Philadelphia, PA; 1996:442-43.
Moretti R, Torre P, Antonello RM, et al. Gabapentin as a drug therapy of intractable hiccup because of a vascular lesion: a three-year follow up. Neurologist. 2004;10:102-06.
Smith HS, Busracamwongs A. management of hiccups in the palliative care population. Am J Hosp Palliat Care. 2003;20:149-54.
Friedman NL. Hiccups: a treatment review. Pharmacotherapy. 1996;16:986-95.
Nagayama T, Kaji M, HiranoH, et al. Intractable hiccups as a presenting symptom of cerebellar hemangioblastoma. Case report. J Neurosurg. 2004;100:1107-10.
Witoonpanich R, Pirommai B, Tunlayadechanont S. Hiccups and multiple sclerosis. J Med Assoc Thai. 2004;87:1168-71.
Morgan JA, Ginsburg ME, Sonett JR, et al. Advanced thoracoscopic procedures are facilitated by computer-aided robotic technology. Eur J Cardiothorac Surg. 2003;23:883-87.
Strate T, Langwieler TE, Mann O, et al. Intractable hiccup: an odd complication after laparoscopic fundoplication for gastroesophageal reflux disease. Surg Endosc. 2002;16:1109.
Dobelle WH. Use of breathing pacemakers to suppress intractable hiccups of up to thirteen years duration. ASAIO J. 1999;45:524-25.
Funakawa I, Terao A. Intractable hiccups and syncope in multiple sclerosis. Acta Neurol Scand. 1998;98:136-39.
FROM THE INTERNET
Martell B. Hiccups. Medical Encyclopedia. MedlinePlus. Update Date: 5/4/2003. 2pp.
Wilkes G. Hiccups emedicine. Last Updated: January 11, 2005. 20pp.
Clark C. Dealing with cases of hiccups. The Pharmaceutical Journal. 30 October 2004. 2pp.
Shmerling RH. The Myth and Mystery of Hiccups. IntelliHealth. March 9, 2004. 5pp.
Singultus (Hiccups). National Center for Emergency Medicine Informatics. NCEMI. nd. 2pp.