The Ins and Outs of Hiccups

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We’ve all had them. They come suddenly, they’re weird, and they’ll always overstay their welcome. We all know the various ways to get rid of them—drinking water, holding your breath, getting a fright—but all of them only work sometimes, and the phenomenon remains a mystery.

For all the knowledge on how to cure this peculiar bodily function, most of us understand very little about what exactly causes them.

What Happens When We Hiccup?

So what exactly happens when we hiccup? The effect that we feel is simply a twitch of the diaphragm, but that’s only the end process. The mechanism is a reasonably complex motor act.

During a hiccup, the diaphragm, the intercostal muscles (external, internal, and innermost, the Subcostalis, and the Transversus Thoracis), and the neck muscles all make a very sudden and dramatic contraction.

Within a fraction of a second of this contraction beginning, the vocal cords (the glottis) close suddenly, making the classic “Hicc” sound that the affliction was named for. In addition, the roof of the mouth and the back of the tongue both move upwards during the process, resulting in a small burp that sometimes accompanies the hiccups.

A bizarre and mostly unknown physiological side effect also occurs—Your heart slows down just a little bit during the hiccup.

As we all know, hiccups seldom occur in isolation and almost always happen at regular intervals, sometimes for as long as a few hours.

As mentioned, some common stopping methods seem to work for some people, but they’re certainly not a one-size-fits-all cure.

Potential Root Causes

Many potential medical and physiological causes might or might not be the root cause of the hiccups. The most common of these is when the stomach distends, and stomach acid rises to the esophagus, usually during or after eating. Hiccups can be a result of eating too fast, but can also be caused by stress of excitement, or drinking carbonated beverages or alcohol. In some cases, it can even be due to temperature changes.

There are also a few other rarer but also possible causes, including disease or irritation in the thorax, phrenic nerve irritation (the nerve connected to the diaphragm, neurological lesions often to do with the brain stem, metabolic disorders, or taking medications that cause acid reflux.

Since hiccups are extremely common, however, these potential causes are not considered by medical professionals unless the hiccups are unusually persistent or arise dramatically at random times.

The most common treatment for regular bouts of hiccups might be acid reflux medication and perhaps a tweak in food consumption to see if that is a potential trigger.