Question

A patient in your clinic has a new diagnosis of chronic phase Philadelphia chromosome positive CML and the provider wants to order treatment with Tasigna (nilotinib). During your drug review, you notice the patient is on fluconazole. Which of the following is true regarding the interaction between Tasigna and fluconazole?

1) There is no interaction, no change is necessary
2) Fluconazole may increase Tasigna concentrations and should be monitored
3) Fluconazole may increase Tasigna concentrations and is contraindicated
4) d. Fluconazole may decrease Tasigna concentrations and in contraindicated

Answer 1

Fluconazole may increase Tasigna (nilotinib) concentrations due to fluconazole's inhibition of the cytochrome P450 enzyme CYP3A4, which is responsible for metabolizing Tasigna. This interaction is significant and fluconazole is contraindicated with Tasigna, necessitating careful monitoring or potential alteration of therapy.

Step-by-step explanation:

The interaction between Tasigna (nilotinib) and fluconazole should be carefully considered in clinical settings. Tasigna, used for the treatment of chronic phase Philadelphia chromosome-positive chronic myelogenous leukemia (CML), is metabolized by the cytochrome P450 enzyme system within the liver, particularly by the enzyme CYP3A4. Fluconazole, a triazole antifungal medication, is known to inhibit CYP3A4 and can thus increase the plasma concentrations of drugs metabolized by this enzyme, including Tasigna. This interaction can result in higher levels of nilotinib in the body, leading to an increased risk of toxicities and side effects associated with Tasigna. Therefore, the correct response is:

Fluconazole may increase Tasigna concentrations and is contraindicated.

It is essential for healthcare providers to monitor drug interactions and potentially select alternative antifungal or antileukemic medications, or adjust doses accordingly under careful medical supervision to ensure patient safety.