Intravenous tacrolimus and cyclosporine induced anaphylaxis: what is next?

Tacrolimus and cyclosporine have been used in various formulations, but their hypersensitivity reactions are rare in practice. Castor oil derivatives are nonionic surfactants used in aqueous preparations of hydrophobic active pharmaceutical ingredients. Castor oil derivatives that can be used as additives to tacrolimus and cyclosporine may play a role in the development of hypersensitivity reactions, especially anaphylaxis. Various immunologic and nonimmunologic mechanisms have been implicated in hypersensitivity reactions induced by castor oil derivatives. Physicians should be aware that not only the drug itself, but also its additives or metabolites could induce hypersensitivity reactions. We report a case of anaphylaxis caused by vitamin K (phytonadine), serotonin antagonist (granisetron), intravenous tacrolimus, and cyclosporine. Interestingly, the patient tolerated oral cyclosporine, which did not contain Cremophor EL or polysorbate 80.