Medication reconciliation is a process of comparing the list of medicines prescribed to the patient before, during and after hospitalisation with the medicines the patient is actually taking. It can also be defined as the comparison of the ''Best Possible Medication History'' of the patient with the therapy prescribed by a doctor. Aim of study: Determine the degree of pharmacotherapy compliance of the previous pharmacotherapy compared to the one prescribed on admission of patients to hospital, the frequency and the type of unintentional discrepancies and frequency of potentially inappropriate medications, all of which contributes to a greater therapy success-rate. Participants and methods: Study was conducted at the Department for gastroenterology at Clinical hospital Dubrava. Participants were older people with an average age of 74,4. The pharmacist reviewed the treatment of the patients after their admission to hospital and compared the results with the best possible medication history. The unintentional discrepancies detected in pharmacotherapy have been classified to the type of discrepancies (omission of the drug, admission of a new drug, changing the medicine within the same pharmacotherapeutic groups, changing the dose, dosing interval and route of administration). It was also conducted the medication review defined by the STOPP and Beers criteria. Results: At admission to hospital it was detected at least one discrepancy in 73,9% of cases in total of 46 patients. 35,5% of them were unintentional discrepancies. At least one unintentional discrepancy appeared in 43,5% of patients. The most common discrepancy was the ommision of drug (63,6%). Potentially inappropriate medications appeared in 17,9% of patients according to the STOPP list and 35,9% according to the Beers list. Conclusion: The important and basic step in the medication reconciliation process is to have an accurate and complete patient’s medication history. The participation of pharmacist in this process, as part of a multidisciplinary team, would minimize the discrepancies in the medication of patients upon their admittance to hospital.