A hiccup or hiccough (generally pronounced "hiccup" independent of the spelling) is an involuntary spasm of the diaphragm; typically this repeats several times a minute. The sudden rush of air into the lungs causes the glottis to close, creating the "hic" noise. A bout of hiccups generally resolves by itself, although many home remedies are in circulation to shorten the duration, and medication is occasionally necessary. By extension, the term "hiccup" is also used to describe a small and unrepeated aberration in an otherwise consistent pattern. The medical term is singultus. more...
While many cases develop spontaneously, hiccups are known to develop often in specific situations, such as eating too quickly, taking a cold drink while eating a hot meal, eating very hot or spicy food, laughing vigorously or coughing, or drinking an excess of an alcoholic beverage. Hiccups may be caused by pressure to the phrenic nerve by other anatomical structures, or rarely by tumors.
It is still unclear to scientists exactly why hiccups occur, particularly because it doesn't seem to give us any specific benefit.
The following are some commonly suggested home remedies. It should be noted that while numerous remedies are offered, the vast majority fall into just a few broad categories. These categories include purely psychosomatic cures centered around relaxation and distraction, cures involving swallowing and eating (with the rationale generally that this would remove irritants or reset mechanisms in the affected region), and cures involving controlled/altered breathing.
While the first two categories may prove effective for many short lived and minor cases of hiccups, those suffering from an intractable case may become desperate sorting through various ineffective home remedies. Many of the cures centered around controlled breathing (i.e. holding breath) are often ineffective. The only underlying rationale could be the displacement of an irritated nerve through prolonged diaphragmatic expansion.
However, one respiratory remedy has a fairly sound rationale underlying it. Breathing into a bag or small enclosed container (ensuring that it is completely sealed around the mouth and nose) induces a state that is termed respiratory acidosis. The effect is caused by increasing the amount of inspired carbon dioxide, which then increases the serum level of carbon dioxide. These increased levels of CO2 lower the pH in the blood, hence creating a state of acidosis. This state of acidosis produces vasodilation and depression of the central nervous system. The effect allows for increased blood flow to the affected muscles, and suppression of the aberrant nervous impulses. Inducing a state of acidemia through hyperventilation is particularly effective in curing hiccups because the diaphragm rests directly against the pulmonary vasculature that is then flowing with especially low pH blood. It should be noted that this is a potentially dangerous action and should only be done with another person present. As the serum CO2 level rises abruptly, the person will begin to feel lightheaded and within a few minutes will pass out. If done without a spotter, the person might either injure him or herself as he or she passes out, or pass out in such a way that the bag or container continues to prevent oxygen intake (see also asphyxia).
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