Background In December 2010 withdrawal of drugs with expired date was done in Clinical Center of Serbia. It was noticed that value of these medicines presented significant part of money invested in medicines.

Purpose The aim of this research was to determine main reasons for large amount of drugs which had to be withdrawn due to expiration.

Materials and methods An inventory of all withdrawn medicines was done. It was noticed that change of protocols (including appearance of modern drugs for one indication on the market), cessation of financing by Republic Institute for Health Insurance (RIHI) and carelessness of healthcare professionals were main reasons that led to expiration date of drug usage. Therefore, all withdrawn medicines were classified in these three groups.

Results Total value of medicines that were withdrawn due to expiration date of usage in 2010 presented 0,045% of money which was spent for acquisition of all drugs in Clinical Center of Serbia. 53.14% of these expenditures were spent on anticancer group of drugs, 32.71% on antibiotics and 14.15% on other therapeutical groups. Medicines that were withdrawn as a result of protocol change or appearance of modern drugs took 51.88% of money invested in dated drugs. On the group of drugs withdrawn due to cessation of financing by RIHI was spent 24.18% of all the money spent on withdrawn drugs. Medicines withdrawn because of carelessness of healthcare professionals occupied 23.94% of money.

Conclusions Even though carelessness of healthcare professionals doesn't occupy the biggest part of expenditures spent on dated drugs, interventions of hospital pharmacists in this area could significantly contribute to money savings. Therefore, special precautions are taken in acquisition of anticancer drug, hospital pharmacists are more involved in drug prescription, communication between medical doctors and hospital pharmacists is improving from day to day, and FEFO principles are to be established through appropriate SOPs.