Background. Plasmapheresis is one of the methods of extracorporeal blood purification involving the removal of inflammatory mediators and antibodies. The procedure is used in a variety of ailments, including autoimmune diseases. The aim of the present study was to analyse the incidence of plasmapheresis-related complications in patients treated in the intensive care unit (ICU). Methods. The analysis involved 370 plasmapheresis procedures in 54 patients. The data were collected from patients` medical records, including procedure protocols. Results. The most common diseases treated with plasmapheresis included: myasthenia gravis (33.3%), Guillain-Barré syndrome (14%), Lyell's syndrome (9.3%), systemic lupus erythematosus (7.4%), and thrombotic thromcytopenic purpura (7.4%). The adverse side effects observed most frequently during plasma filtration were decreases in arterial blood pressure (8.4% of all procedures), arrhythmias (3.5%), sensations of cold with temporarily elevated temperature and paresthesias (1.1%, each). In most cases, the symptoms were mild and transient. Severe and life-threatening episodes, i.e. shock, drops in arterial blood pressure requiring catecholamines administration, persistent arrhythmias and haemolysis, developed in 2.16% of procedures. Conclusions. Plasmapheresis can be considered a relatively safe method of treatment of ICU patients. Continuous observation and proper monitoring of patients provided by highly trained medical personnel are essential for its safety.