Hiccups occur as a result of sudden, involuntary contractions of the diaphragm, the thin muscular membrane that divides the chest and abdomen and is involved in breathing. When the diaphragm tightens, the vocal cords suddenly close, which results in the characteristic “hic” sound being made at the top of the windpipe.

Hiccups are very common, with most people experiencing them at some point in their lives. They may occur in the absence of any trigger, but episodes of hiccupping have been associated with eating a large meal, drinking alcohol, becoming excited or stressed, eating too quickly, smoking, eating spicy foods, and drinking fizzy or hot drinks. Generally, hiccups are not a serious problem and only last a few minutes, but in some cases, they persist for a long time and even for months.

Hiccups that do not pass after two days are referred to as “persistent” or protracted” and if the problem lasts for more than a month they are referred to as “intractable.” In the rare instance of hiccups lasting for these longer periods, an underlying medical condition may be the cause and people who experience recurring hiccups or those that last for more than two days should visit their doctor to check whether any tests or treatments are needed.

Since hiccups generally pass after a short period, treatment is not usually necessary. However, if hiccups are persistent or causing problems with breathing, sleeping, or eating, there is a number of techniques people can use to eliminate them. There is no certain way to stop hiccups, but the following may help to provide relief:

• Breathing into a paper bag
• Gargling with or sipping ice-cold water
• Holding the breath
• Pulling knees towards the chest to compress the diaphragm
• Biting on a lemon
• Tasting vinegar
• Swallowing a teaspoon of granulated sugar
• Leaning forwards so that the chest is compressed
• Pulling on the tongue
• Sneezing
• Swallowing large amounts of water while the nostrils and ears are closed
• Performing the valsalva maneuver – this involves forcing breath out while the nostrils and mouth are closed

Although these techniques may provide relief in some cases, they have not been clinically tested, meaning it has not been proven how effective they actually are.