THURSDAY, Aug. 16, 2001 (HealthDayNews) -- Ordinary iron supplements could provide relief from the dry, hacking cough that forces some patients to stop taking ACE inhibitor drugs for their heart conditions, Korean researchers report.
ACE inhibitors are widely prescribed to improve survival and reduce complications for people with high blood pressure, heart failure and other cardiac conditions. Perhaps 20 percent of people taking the drugs experience a chronic cough that some find unbearable.
Researchers, led by Dr. Kyung Pyo Hong, chief of the division of cardiology at Samsung Medical Center in Seoul, say a small daily dose of iron provided significant relief for most patients in a small but carefully controlled study. The finding is reported in the August issue of the journal Hypertension.
The six men and 13 women in the study, all with persistent coughs attributed to ACE inhibitors, were asked to keep daily diaries rating cough-related symptoms on a scale of 1 to 7 before and after they began taking either 256-milligram ferrous sulfate tablets or a placebo.
The average cough score was 3.07 before the study began. It dropped to 1.69 after four weeks for the patients who took the iron tablets, but remained virtually unchanged for the placebo group. Eight of the 10 iron takers but only one of the placebo takers reported improvement in their cough problem.
A treatment for the cough problem would be welcome because "right now there are no treatments other than stopping the medicine," says Dr. Joseph A. Diamond, an assistant professor of medicine specializing in hypertension at the Mount Sinai School of Medicine in New York City.
ACE -- angiotensin-converting-enzyme -- inhibitors block an enzyme that produces angiotensin 2, a molecule that tightens blood vessels and thus lowers blood pressure and stress on the cardiovascular system. But they also increase blood levels of another molecule, bradykinin, that induces a cough.
"In most cases, the cough is not very troublesome, but a small percentage of patients say they are coughing all the time," Diamond says.
Many doctors are concerned about persistent coughing when prescribing an ACE inhibitor, says Dr. Jay A. Gold, senior vice president of MetaStar, Inc., a company that counsels physicians in the Medicare program.
"My work involves persuading physicians and hospitals to use ACE inhibitors more consistently," says Gold, whose company has no ties to pharmaceutical manufacturers. "This is very important for patients whose cardiac function is compromised. Studies have made it very clear that ACE inhibitors have a positive effect on their health. When I talk to physicians about why they are not prescribing ACE inhibitors, there is a real concern about cough. Obviously, if you can find a way to cut down on cough, you can make it easier for physicians to prescribe ACE inhibitors. That is why this study could be important."
Gold, Diamond and the Korean researchers say more work is needed before wide use of iron supplements can be considered. The small number of patients in the study is one concern, they say. Another is the possibility of side effects caused by interaction of the iron with the drug.
Studies of patients given intravenous iron to treat kidney conditions while they were taking ACE inhibitors found several side effects, such as fever, joint pain and allergic reactions, Gold and Diamond say.
"If this ever is commonly used, you would have to be careful in terms of the doses or the way the iron is put together with the medication to be sure you would not get serious side effects," Gold says.
What To Do
Anyone bothered by a cough related to ACE inhibitor treatment should not take an iron supplements before consulting a doctor.
Learn more about ACE inhibitors and other high-blood-pressure drugs from the American Heart Association or St. James's Hospital of Dublin.
