[Complications of heparin administration].

Heparin as an indirect anticoagulant is used in the clinical practice for more than 60 years. It is an effective drug, but it has limitations. To the side effects belong the heparin resistance, risk of bleeding (haemorrhage), hypersensitivity reactions and heparin-induced osteoporosis. The low-molecular-weight heparins exhibit fewer side effects, but it is still necessary to know about them.