Objectives: The increased complexity of medical therapy and surgical procedures while increasing the cost of treatment has enabled the clinical evolving profession of hospital pharmacist in th emid-twentieth century. It has been shown that clinical pharmacist provides safe and effective use of drugs while reducing health care costs. Although the role of the clinical hospital pharmacist as an important part of th emultidisciplinary team has been studied, little is known from the literature about the impact of pharmaceutical interventions on optimizing pharmacotherapy in abdominal surgery patients. In Croatia so far has not been found any such literature information. Material and methods: The prospective survey was conducted in the period from 01 October 2014 to 31 March 2015, at the Department of abdominal surgery, General Hospital „Dr. Tomislav Bardek“ Koprivnica. All patient shospitalized at the Department in the examined period were included in the study. A daily analysis of pharmacotherapy was provided for each patient using a form that has been created by the pharmaceutical team led by an experienced clinical pharmacy specialist. The study was conducted by analyzing the pharmacotherapy of patients after a morning ward round, using LexiCompOnLine®, databases such as medicine bases of the Croatian Agency for Medicinal Products and Medical Devices (HALMED), MEDLINE®, Medscape®. The pharmaceutical interventions (PI) were documented on a form entitled "Pharmacotherapy analysis" which was presented to the physcian team on the next day morning rounds. The original form was archived in the medical patient records and a copy in the archives of the hospital pharmacy. Clinical significance of PI was evaluated using the above databases and medical records. Acceptance rate was noted as a change of therapy which has been seen on the next day while controling the pharmacotherapy. Results: The study included a total of 539 patients, of which 54% (n = 292) were men. A total of 3773 therapy forms were analyzed of which there were 57 PI wherein more than half (n = 30 or 52.63%) of the interventions were accepted. The most common drugs involved in FI were drugs that affect nervous system (38,37 %), musculoskeletal system (20,93%), and cardiovascular system (13,95%). Drug interactions stage D and X were the most common type of intervention (77%) of which almost half were accepted (47,73 %). All interventions regarding dosing interval (n=6) and duplication of therapy (n=1) were accepted. Conclusion: The study confirmed the importance and essential role of clinical pharmacists as part of the multidisciplinary team, especially in abdominal surgery patients. With the knowledge based on clinical evidence, pharmacists´ accepted interventions by physicians can optimize pharmacotherapy and patient safety.