Successful switch to oral tacrolimus in a patient with hypersensitivity reaction to parenteral vitamin K, cyclosporine, and tacrolimus: A case report.

Introduction: Calcineurin inhibitors are widely used for the prevention and treatment of graft versus host disease in patients undergoing allogeneic hematopoietic stem cell transplantation, and successful treatment with calcineurin inhibitors is very important for the management of these cases.

Case Report: A 19-year-old man with thalassemia major experienced hypersensitivity reaction to parenteral vitamin K, cyclosporine, and tacrolimus before hematopoietic stem cell transplantation. All three episodes of reaction appeared a few minutes after administration of offended drugs and cause systemic signs and symptoms of anaphylaxis, i.e. itching, flushing, difficulty in breathing, and hypotension.

Management And Outcome: Hypersensitivity reaction was fully controlled by immediately discontinuing the drug and administering hydrocortisone, chlorpheniramine, epinephrine, and intravenous fluids. During hospitalization, the patient tolerated oral tacrolimus without any complication.

Discussion: It appears that Cremophor EL (polyoxyethylated castor oil) which acts as a carrier, solubilizer, and emulsifier in intravenous calcineurin inhibitors is responsible for the occurrence of anaphylactic reaction (anaphylaxis); therefore, it is suggested that the administration of cremophor-containing drug should be avoided in patients with a previous history of hypersensitivity reaction to one of these drugs.