Figure 2

Relationship between pholcodine exposure, IgE sensitization, and quaternary/tertiary ammonium epitopes (QAI) and estimated risk of IgE-mediated anaphylaxis when receiving suxamethonium during induction of general anesthesia in Norway. IgEab, is the abbreviation of IgE antibodies. The relationships depicted apply for the years before 2007 when pholcodine (PHO) was taken off the Norwegian market. PHO exposure is given as estimated by the former marketing authorization holder in Norway. Percentage IgE-sensitized to PHO and the relative distribution of IgE specificities to the QAI and the non-QAI epitopes of PHO, respectively, is taken from studies by Florvaag et al. [5, 6]. The risk estimates for anaphylaxis during general anesthesia with NMBAs for the general population and individuals IgE sensitized to the QAI epitope before anesthesia with suxamethonium are taken from Harper et al. [22]. Risk is given as the ratio of anaphylactic reactions to number of uneventful general anesthesias using a NMBA. Approximate number of populations in millions is given in italics.