Case of a patient with acute lymphocytic leukemia (ALL) who developed serious adverse reactions caused by drug interactions between vincristine (VCR) and itraconazole (ITCZ)

Abstract

A 51-year-old man diagnosed with acute lymphocytic leukemia, was treated with a multi-drug regimen including vincristine (VCR), along with itraconazole (ITCZ) as prophylaxis against potential fungal infections. He developed adverse reactions, included constipation, numbness of the extremities and hyponatremia, in addition to hepatic damage, all of which were thought to have resulted from the use of VCR, with ITCZ was discontinued, the fluid replacement volume was decreased along with sodium supplementation, and the patient's condition improved. Vinca alkaloids are metabolized by CYP3A4, an isoform of cytochrome P450. In this connection all of the azole antifungals are known to inhibit CYP3A4 inhibitors. In our case, the serious adverse reactions observed were thought to have resulted from the drug interactions between VCR and ITCZ which led to a delay in VCR metabolism.