In the last two decades the number of Internet users increased from 1 to 51% of the global population. The figure increased tenfold between 1999 and 2013, and doubled in the past five years. Nowadays 830 million young people aged 15–24 are online, representing almost 25% of the total number of Internet users globally. In 1996 Kimberley Young was the first researcher to bring attention to the negative consequences of Internet use, by demonstrating the presence of the clinical symptoms of addiction and indicating a severe impulse control disorder among some Internet users. Various aspects of the Internet-related disorder have been analysed, initially focusing on defining the phenomenon and examining specific addictive patterns of behaviour, and now primarily investigating the etiological factors and major trends in the development of the disorder. Controversy has quickly grown around the various related issues. There have been discussions about whether Internet Addiction represents a manifestation of an underlying disorder, or constitutes a separate disease. At present, there are no protocols endorsed for pharmacological treatment; the majority of reports describe the empirical treatment of individual cases, and the available studies are lacking consistency in the definitions used, randomization of groups studied, appropriate control groups or information about treatment effects. It seems that at present our knowledge of the neurobiological processes related to Internet Addiction is too basic to formulate any pharmacological recommendations. The presence of disorders in the reward system is suggested and the implementation of therapeutic procedures advised accordingly. The aim of this publication is to review the scientific reports available to lay the foundations for further discussion.