ACE Inhibitors and Angioedema

May 2, 2012 — Tens of millions of people in the United States take an ACE Inhibitor medication to treat high blood pressure (hypertension), cardiovascular disorders, diabetes, and kidney problems. Now, doctors are warning these people about the risk of angioedema.

This life-threatening side effect can cause rapid, severe swelling of the face, tongue, and throat, which can block a patient’s airway and cause death. One doctor says: “If you have swelling, stop the drug and call 911, because minutes can matter.”

When you used an ACE inhibitor, you may have been unaware about the risk of angioedema. Some doctors are concerned that there is not a strong enough warning on the labels of ACE inhibitors. When people develop swelling, they may delay treatment because they do not realize the swelling can rapidly become deadly.

In 2002, an emergency medicine physician named James Feldman sent a petition to the FDA asking the administration to place a “Black Box” warning on ACE Inhibitors. The “Black Box” is the administration’s strongest warning, and it is reserved for deadly side effects of a medication. Within 6 months, Dr. Feldman treated 4 patients with life-threatening ACE inhibitor angioedema.

Dr. Feldman wrote in the petition:

“Patients who develop life threatening upper airway obstruction from ACEI are among the most challenging patients encountered in the practice of emergency medicine. Such patients often present with massively distorted anatomy, protruding and enlarged tongues, and may have anatomic features (short, large neck) that may make it quite difficult to establish a surgical airway rapidly should intubation be impossible.”

The FDA ultimately denied Dr. Feldman’s request to include the Black Box warning. The administration felt that the “the current labeling of ACE inhibitors educates physicians about the potential reaction and adequately protects public heath.” Furthermore, “a boxed warning is unlikely to reduce the incidence.”

It is unknown exactly how many people suffer from ACE inhibitor angioedema every year. Studies have estimated that fewer than 1% of patients will get angioedema. However, ACE inhibitors are used by tens of millions of people in the U.S. to treat a wide variety of ailments. Because so many people use these medications, even a small risk translates to potentially tens of thousands of life-threatening ACE inhibitor angioedema cases.

Even more troubling, the risk appears to be greatest for black people. One study found that, between 2000 to 2009, the rates of ACE inhibitor angioedema increased from 8.9 to 18 per 100,000 taking the drugs. Black people made up 37% of all ACE inhibitor angioedema cases.

Another study analyzed 91 cases of ACE inhibitor angioedema. Of these cases, 35% needed treatment in the intensive care unit, 4% needed to have a breathing tube inserted, and one patient died.

ACE Inhibitors include popular brand-name drugs Vasotec and Zestril. Generic ACE Inhibitors include captopril, enalapril, lisinopril, and ramipril. These medications work by forcing the smooth muscles along blood vessels to relax, causing the blood vessels to widen. This makes it easier for blood to flow through the body, and lowers blood pressure. Unfortunately, in some people, the medication can cause the blood vessel to widen too much. The vessel then leaks fluid into nearby tissue, causing it to swell rapidly. This is called angioedema. When the swelling occurs in the mouth or throat, the patient can easily suffocate to death.