This book deals with role of genetic polymorphism in Tramadol related toxicities among Egyptian addicts. Tramadol addiction leads to destruction of the individual and society, destruction of the individual; where it destroys him completely, and exhausting his strength, and afflicted by many diseases, becomes a useless person, dependent on his family and society. treatment of Tramadol addiction is too complex, and different strategies have been employed without effective outcomes. This push researches to find new treatment modalities where genetic testing plays a pivotal role. Genetic testing helps in identification of high risk addicts whom to develop target organ toxicities as well as management of addicts. In this book you can find the association between CYP2D6 gene polymorphism and susceptibility to Tramadol induced toxicities, and which genotype was the prevalent one among Egyptian addicts who develop such toxicities.