SAN DIEGO -- If you have asthma you may also be suffering with another condition: acid reflux.

The connection is being studied by the American Lung Association and University of California, San Diego, researchers.

They are investigating whether a popular acid reflux drug can help people with both conditions.

Kerry Hebert, 31, often finds herself breathless because of asthma.

"It feels like somebody is taking your air tubes and squeezing them," said Hebert.

When Hebert is not fighting to breathe, she's dealing with another health problem.

Acid reflux or "gerd" is common in people with asthma.

"If you wake up in the morning with respiratory difficulties from asthma... one possibility is that you were having reflux during the night," said UCSD researcher Dr. Stephen Wasserman.

Wasserman is heading a study to determine whether a popular acid-reflux drug called Nexium can ease symptoms of both acid reflux and asthma.

The drug, a proton pump inhibitor, has shown promise in easing asthma in animals who did not have acid reflux.

Hebert never realized acid reflux could be the cause of her frequent sore throats.

Since Hebert enrolled in the study three months ago, she religiously takes a tablet twice a day.

Hebert doesn't know if it's Nexium or a placebo pill, but she says she's noticed a positive change in her breathing.

Researchers say they don't know if treating people for acid reflux will help their asthma control, but they are hopeful.

If you are interested in finding out more about the study, call the UCSD Clinical Trials Center at 888-UCSD-AIR.