OBJECTIVES: :Our objective was to compare cost saving before and after of pharmaceutical care implementation and Octreotide use evaluation at surgical ward. METHODS: This study was conducted during October 1, 2008 to April 30, 2009. The research instruments were octreotide use criteria with approval by surgical staffs. Pharmacist reviewed and evaluated the medical chart in order to identify medication related problems by focusing on medication regimens. Medication related problems were classified into three categories: inappropriate route, inappropriate duration and inappropriate indication of administration. Cost saving was based on drug costs. The pre- and post-pharmaceutical care implementation and octreotide use evaluation results were compared and analyzed with descriptive retrospective statistics and paired t–test at 95 % significant level. RESULTS: There were 302 patients received Octreotide. 193 patients (63.9%) were prescribed Octreotide appropriately. Medication related problems were found in 109 patients (36.1%). The most frequent problems were inappropriate duration (44.95%), inappropriate indication (34.86%) and inappropriate route of administration (20.18%). The cost of Octreotide use for inappropriate duration, inappropriate indication and inappropriate route of administration were significantly decreased after pharmaceutical care implementation 3,062,160 versus 1,946,400 baht, 657,000 versus no money, and 919,800 versus 226,800 baht, respectively (p <0.005). The total cost of Octreotide use was 9,529,950 baht reducing to 7,015,008 baht after pharmaceutical care implementation with statistically significant (p <0.005). CONCLUSIONS: The implementation of pharmaceutical care and evaluation of Octreotide use resulted in significant cost saving. The drug utilization program, consisting of deriving quality criteria for prescribing, structured order form and good cooperation between physicians and pharmacists with strong support of the therapeutics committee, was an effective strategic approach to promote rational drug use and develop Octreotide use guidelines.