For some healthy adults, getting sick enough to require medication is only half of the problem. The other is getting that pill to go down. Stephen Cassivi, a thoracic surgeon at the Mayo Clinic in Rochester, Minn., who specializes in esophageal disorders, offers one explanation for why some people find it difficult to swallow pills.

Fear Factor

Cassivi says the reasons some people can't even get a baby aspirin to go down the esophagus are varied. "People who have underlying swallowing difficulties, called dysphagia, may have trouble swallowing pills, but that is generally the result of other problems, such as stroke or surgery or gastroesophageal reflux," he says.

For the rest of the population, Cassivi notes, pill-swallowing difficulty is usually related to a fear of gagging, which might come from a bad experience with taking a pill. "Fear of gagging is pretty prominent" and a bad experience can cause one to think a pill is harmful and thus cause the throat muscles to tighten, he says. To swallow pills without worry, one has to "get over the mental hump" and relax the muscles.

It's Just a Phase

There are three phases to swallowing: oral (chewing, moistening and delivering food to the back of the mouth); pharyngeal (which includes the closure of the larynx by the epiglottis and vocal cords, and the temporary inhibition of breathing as the food passes); and esophageal (the rhythmic contractions of the esophagus to deliver food to the stomach, among other actions).

"We have an unconscious ability to know when food is moistened and masticated enough to be delivered to the back of the throat," Cassivi says. For instance, no one chews yogurt—typically one just swallows it—but not being able to chew a hard substance like a pill can throw the mind-body connection in swallowing off, he says.

The oral phase is the voluntary phase and may be the key to helping many people overcome pill-swallowing difficulties.

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