Chronic urticaria and intermittent anaphylaxis. Reactions to lophendylate.

In a case of chronic, severe urticaria and intermittent episodes of anaphylaxis due to an iophendylate injection (Pantopaque) given in the course of myelography, almost complete relief was obtained from the removal of approximately 8 ml of residual iophendylate from the spinal canal. Data obtained from direct skin testing, Prausnitz-Küstner testing, peptide inhibition of Prausnitz-Küstner testing, and IgE levels quantitated before and after removal of iophendylate indicate that these symptoms were mediated via an IgE anti-iophendylate reaction.