Bioavailability of Tyrosine Kinase Inhibitors: An Added Component of Assessment

The growing prominence of tyrosine kinase inhibitors (TKIs) as treatment for malignancies prompts oncology nurses to expand the scope of their patient assessment. Because TKIs as oral agents have a different bioavailability than parenteral agents, factors that alter drug absorption and metabolism can have a measurable effect on the amount of active, available drug when TKIs are prescribed. In relation to TKIs as cancer therapies and intended dosing, this article reviews three drug absorption and metabolism factors: changes in stomach pH, as well as P-glycoprotein and cytochrome P450 interactions.