There are five levels of warnings to the physician beginning with a list of adverse reactions and ending with the most serious – the Black Box. Unfortunately, the FDA has never issued rules defining the requirements for the application of a Black Box warning and, therefore, there is no specific level of seriousness that says a Black Box warning should be applied. It is of interest that not all drugs with the potential for serious side effects or death actually carry a Black Box warning. Currently in the world of allergy, there are five drugs with Black Box warnings: Long-acting beta agonists (1. Salmeterol [in Serevent, Advair] and 2. Formoterol [in Brovana, Foradil, Perforomist, Symbicort]); Topical calcineurin inhibitors (3. Tacrolimus [Protopic] and 4. Pimecrolimus [Elidel]); and the biologic response modifier omaluzimab (5. Xolair ). A sixth drug, very occasionally used by allergists, with a Black Box is the ketolide antibiotic (6. Ketek ). While there is little disagreement about the side effects caused by Xolair, there is a fair amount of disagreement about the scope of the side effects resulting from the long-acting beta agonists and the topical calcineurin inhibitors. [Excerpted from an article by Donald W. Aaronson, M.D.] I have been able to completely avoid using Ketek with my patients. The latter 2 classes of drugs remain in widespread use because physicians and their patients accept the questionable risks and usually get strong improvement from using these drugs. When indicated, I usually have no reservations about using these 2 classes of drugs to treat allergic diseases. In addition, when the opportunity presents itself, I recommend tapering use of these drugs, which minimizes any risk, and reduces the patient's overall drug burden. If you have a question about this, ask your doctor.