Constant hiccups are usually caused by disturbances that lead to irritation of the phrenic and vague nerves, which innervate the diaphragm. The diaphragm is a muscle that separates the thorax from the abdomen and participates in the breathing movements. Disorders that irritate the vagus and phrenic nerves can cause irregular movements in the diaphragm, causing the hiccups.
Although hiccups may be related to illnesses, some of them serious, most of them arise in common situations like after eating a lot, drinking alcoholic drinks and soda, laughing a lot, sudden changes in temperature and intake of hot or cold liquids. In these cases, it is benign and tends to disappear after some time.
Some possible causes for the appearance of constant hiccup are: reflux esophagitis, anxiety and stress, gastroesophageal reflux, neurological disorders and after some surgical procedures and anesthesia.
Hiccups lasting up to 48 hours are considered acute. If they last longer than 48 hours, they are considered to be persistent. In any of these situations the general practitioner should be sought for the identification of its cause and treatment.
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