Drug Might Restore Sense of Smell

July 11, 2009 -- A drug once used to treat asthma and other respiratory conditions shows promise in restoring a sense of smell to those who have lost that precious ability.

"More work needs to be done but, for patients for whom other treatments don't work, this may be an option worth trying," said Dr. Ronald Kuppersmith, clinical assistant professor of surgery at Texas A&M Health Science Center College of Medicine and president-elect of the American Academy of Otolaryngology-Head and Neck Surgery.

The drug, theophylline, does have side effects and is now out of vogue for asthma and related disorders, said Kuppersmith, who was not involved in the study.

According to background information in the article, about 20 million people in the United States have some degree of hyposmia, or loss of the sense of smell, affecting their ability to enjoy the flavor of artichokes and the fragrance of azaleas.

"There's a whole spectrum from having mild changes in your sense of smell to complete loss," Kuppersmith said. "It can be very frustrating for the patient, but also for the physician. A lot of people can't enjoy coffee because they can't smell it. They lose weight. They can't smell flowers."

Any number of things can cause the problem. "The most common causes are viruses, head trauma, severe allergies or some kind of anatomic obstruction in the nose or nasal polyps," Kuppersmith explained.

In June, U.S. health officials warned consumers to stop using Zicam nasal cold remedy products because they can cause the loss of a sense of smell.

According to Dr. Robert Henkin, lead author of the study that appears in the June issue of the American Journal of the Medical Sciences, there are few effective treatments out there.

Henkin, director of the Center for Molecular Nutrition and Sensory Disorders in Washington, D.C., and his colleagues had previously discovered that people with hyposmia had reduced levels of cyclic nucleotides in their saliva and nasal mucous, and that treatment with theophylline had increased levels of this growth factor and restored some of the sense of smell.