Background: Great progress has recently been made in immunotherapy of solid carcinomas. The advent of immunotherapy with checkpoint inhibitors has brought not only a completely different mechanism of action but also different types of adverse reactions. These adverse reactions are similar to those of autoimmune diseases and are referred to as immune-related adverse events. Most adverse reactions are due to lower grade toxic effects. Neurotoxicity is a less frequent. On the other hand, with the spread of immunotherapy, it can be assumed that adverse events with a lower incidence may occur in a relatively higher frequency due to borader usage of immunotherapeutics and thus, physicians outside of cancer centres may be presented with these events. The main therapeutic intervention is immunosuppressive therapy with corticoids. However, in some cases, or in case of delayed intervention, they may be fatal. Purpose: Therefore, it is of great importance to increase the physician’s and patient’s knowledge of the possible complications of this promising treatment modality. It is essential to apply proper management and help patients engage positively to prevent these situations occurring.