Interferon beta 1a anaphylaxis, a case report. Standardization of non-irritating concentration for allergy skin tests.

Multiple sclerosis is a disease with a potentially severe prognosis and epidemiologically increasing. Interferon beta 1a is a very useful maintenance therapy widely used by neurologists. In the literature, there are several case reports of  hypersensitivity reactions. In this case report we describe an anaphylactic IgE mediated reaction to interferon beta 1a. We also describe, for the first time in the medical literature, the non-irritating concentration (NIC) to be used for skin tests.