Switching cough off

Most of the time, there’s nothing to do about a cough other than wait until it passes. Most cough medicines either don’t work very well or have serious side effects, like drowsiness. This isn’t what you want to hear if you’ve been coughing for days. But recent research has turned up a possible new way to cure a cough.

Coughing may come with the common cold or it may be triggered by smoke or pollen in the air. There’s always a trigger, though we don’t always know what it is.

Doctors and scientists don’t fully understand coughing. But recent studies suggest that nerve cells in the body’s airways may point to a new way to treat coughing. Nerve cells are messengers: They send information from parts of the body to the brain, and from the brain back to the body. On the outside of nerve cells are molecules called receptors. Irritants like smoke and pollen that get inside the body’s airways through the mouth and nose stick to these receptors. Then the nerve cell sends a message to the brain, and the brain responds with a clear order to the body:

Cough!

Scientists are investigating these nerve cell receptors because if they can be blocked — at least for a while — then maybe the coughing will stop. One of these receptors, called TRPV1, caught scientists’ attention because it plays a part in coughing and in feeling pain. A medicine that blocks this receptor may relieve pain and coughing. However, further studies soon revealed that blocking this receptor caused people to feel temperatures differently, which might make them more susceptible to burns.

More recently, scientists have focused on a receptor called TRPA1. This receptor detects an ingredient in wasabi and mustard oil that gives these foods their punch.

This same receptor also responds to a wide variety of breathing irritants, including garlic and tobacco smoke, Sven-Eric Jordt told Science News. Jordt, a scientist who helps develop new medicines at Yale University, led a study on TRPA1. So far, blocking TRPA1 with drugs seems to be a safe treatment, but more studies are needed before scientists can determine if it can cure coughing. If all goes well, says Jordt, TRPA1 might lead to a new kind of cough medicine — and a new approach to treating cough.

Most cough medicines are swallowed and have to travel through the body to get to the lungs. But “what I think may be better for cough is producing a formula that has to be inhaled,” Jordt told Science News.

The recent studies on receptors as possible targets for cough medicine show that cough research is picking up.

“Cough in general has until recently been grossly under-researched,” Peter Dicpinigaitis told Science News. Dicpinigaitis is a pulmonologist, which means he’s a doctor who treats diseases that affect how we breathe. He runs the Montefiore Cough Center in New York City. Sometimes, when Dicpinigaitis arrives at work, he finds that his waiting room is full of patients who have traveled far for his help. Perhaps one day he’ll be able to offer them a better cure for cough.

POWER WORDS (adapted from the New Oxford American Dictionary and the American College of Physicians)

pulmonology The area of medicine concerned with diseases of the respiratory system.

nerve cell A cell that transmits nerve impulses.

receptor A molecule on the outside of a cell that responds specifically to a particular substance.

respiration The act of breathing.