The International Classification of Diseases (ICD) was implemented by the WHO to classify diseases and medical procedures. It is updated regularly, usually every 10 years. The ICD is widely used for the refund purposes and funds deployment in the healthcare system. Due to the rapid development of medicine, the need for detailed recording of new clinical situations increased. The current version of the ICD-10 began to lose its relevance. In 2011 WHO began to work on the new version of ICD. The latest version of ICD-11 will be effective from January 1, 2022. In the article we present the differences between the current ICD-10 and ICD-11 classification, updated rules for classifying and characterizing diseases and describe the newly created chapter on allergic diseases.