Chances are, you know someone right now who is taking chemotherapy drugs. Oral chemotherapy drugs have become quite popular in treating cancer as they can reduce the amount of time patients have to stay in the hospital. But a new study has found that certain common medications may negatively interact with these oral cancer drugs, reducing their efficacy or increasing their toxic side effects.

The study, which was presented at the 2012 American Society for Clinical Pharmacology and Therapeutics (ASCPT) Annual Meeting, was compiled by Medco Health Solutions Inc. The research team found that 23-74 percent of patients were taking one of nine oral cancer drugs along with another medication that interfered with it.

The cancer drugs which the researchers studied are called oral kinase inhibitors and included Imatinib (Gleevec,) Erlotinib (Tarceva,) Dasatinib (Sprycel,) Everolimus (Afinitor,) Lapatinib (Tykerb,) Nilotinib (Tasigna,) Pazopanib (Votrient,) Sorafenib (Nexavar,) and Sunitinib (Sutent.) The medications that interfered with these cancer drugs included calcium channel blockers, certain antibiotics, antifungal medications, some steroids, and proton pump inhibitors.

Researchers also found that in the majority of cases, the cancer medications were prescribed by one doctor while the other medicines were typically prescribed by another, emphasizing the need for better communication between doctors and the need for patients to take more responsibility for understanding the names of medications that they are currently taking and communicating these to other doctors on their health care team.

Not surprisingly, Medco has something to gain by reporting on this problem. The company is a pharmacy benefit manager that offers a program that would alert doctors about potentially troubling medication interactions. So take their recommendations with a grain of salt. But if you are taking medication - any type of medication - be sure you know what it's called and what it's for so that you can tell all the doctors on your health care team before other medications are prescribed.

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