Objectives: To characterise the pharmaceutical care provided by a clinical pharmacists working in a tertiary health care institute, where the extent to which the pharmacist contributes to changes in prescribing patterns use of medications, and patient knowledge was described. Methods: A retrospective single cohort study design was used. Qualitative and quantitative evaluation of a documented pharmaceutical care plan was undertaken. Electronic pharmaceutical care descriptor (Microsoft Access® database) was used for analysis. 167 patients [mean age of 53 yrs, 70% male] from a Medical Health Centre in a tertiary hospital where a clinical pharmacist had provided a medication review. The study patients were those who had either been admitted to cardiology or infectious disease wards. Results: There were 291 pharmaceutical care issues [PCIs; mean per patient (2)] comprising of 67% (n=194) relating to treatment monitoring and 33% (n=97) relating to treatment changes, representing a total of 291 drug therapy problems [DTPs; mean per patient (2)]. The resolution rate of DTPs was 70%, where 61% of recommended changes and 75% of recommended monitoring were implemented. Conclusion: The clinical pharmacist successfully addressed most PCIs while attending ward rounds, reviewing in-patient prescriptions and counselling discharged patients. The electronic pharmaceutical care plan was very effective in recording the pharmacist's ward activities and the pharmaceutical care provided. However, further studies are required in order to explore longterm clinical pharmacists in-put using a well established electronic care plan; part of Al-Shifa computer system in Omani health centres.