On July 7, 2007, the U.S. FDA said the popular asthma drug Xolair will now carry a “black box” warning – the FDA’s most serious warning – because the drug may cause patients to have a severe allergic reaction.

The black box will warn patients of anaphylaxis, signs of which include:

wheezing, shortness of breath, cough, chest tightness, or trouble breathing; low blood pressure, dizziness, fainting, rapid or weak heartbeat, anxiety, or feeling of “impending doom;”
flushing, itching, hives, or feeling warm; swelling of the throat or tongue, throat tightness, hoarse voice, or trouble swallowing.

The warning adds patients may experience anaphylaxis immediately after injecting Xolair or hours later. It may happen after the first injection of Xolair or after receiving many injections. The FDA also urges patients who think they are experiencing anaphylaxis to contact their physician immediately.

Source: FDA Healthcare Professional Information Sheet, updated July 7, 2007.