Safety and Efficacy of Phytomedicines in Cancer Prevention and Treatment

Abstract In this review we discuss some aspects of herbal use either to prevent
cancer or to treat the disease or the side effects of chemotherapy. The most powerful
reasons, for cancer patients, to use phytomedicines are related to the wish to leave no
option untried and to the dissatisfaction with mainstream oncology treatments. In the
review, herbs commonly used in cancer and their mechanism of action are referred.
Moreover, clinical trials about the use of some herbs for treating the side effects of
chemotherapy and radiation are cited.

As regards the safety data of phytomedicines in cancer patients, considering the narrow therapeutic window of chemotherapic drugs, the risk of clinically relevant herb-drug interactions can increase: in the USA more than 100,000 deaths per year can be attributed to drug interactions, most of them connected to the use of herbs. Some experts believe that the potential risk of herb drug interactions is enough to recommend patients on chemotherapy not to
use herbal therapies.

At present, oncologists must be encouraged to discuss herbal use with their patients, and they should be aware of possible herb anticancer drug interactions. Furthermore, physicians should advise patients to refrain from using herbs, especially when their effects have not been well investigated.