Targeted therapies are increasingly being used in the medicinal therapy of tumors. The targeted manipulation of molecular signalling pathways or immune reactions can result in adverse effects which are in part novel and require special attention. Research and analysis of the literature. This article reviews the side effects of multikinase inhibitors, MAP kinase inhibitors (in particular EGFR, KIT and BRAF inhibitors) and CTLA-4 inhibitors and discusses the management. The knowledge of these side effects must be thoroughly inccorporated in the clinical examination and the treating physician should have a comprehensive knowledge of them.