The role of Complementary and Alternative Medicine (CAM) treatments in oncology has always been heavily debated. It is estimated that about half of cancer patients experience at least one form of CAM through their life and because of the growing spread of these on the internet, the proportion is destined to grow. There is no clear distinction between alternative and complementary treatment due to the possibility to use the same remedy both alongside and instead of traditional therapies. The use of CAM may expose the patients to a wide spectrum of risks that may range from under treatment due to the delay in using official medicine treatment, to toxicities derived both as a direct consequence of the alternative molecule or because of drug interaction with conventional treatments. Because of the uncertainty regarding the risk-benefit ratio and the fact that the patients often do not declare their use if no specifically requested, this topic is relevant for physicians. Aim of this review is to cover the preeminent CAM, their supposed benefits, toxicities and interactions with conventional therapeutic agents.