OBJECTIVES: To assess the impact of clinical pharmacist intervention (CPI) on prescribing habit and cost saving throughout 12 months duration for patients receiving some and the same medications include (Human Albumin 20% 50ml, Meropenem 500 mg and Ciprofloxacin 200 mg), this was via a comparison made between the NO-CPI (observation only) and Direct-CPI phases, in term of the number of vials dispensed monthly.  METHODS: It is an observational cohort study and it is divided into two phases; Phase-I: to evaluate prescribing habit of the prescribers throughout two months duration  (30 days with NO-CPI and 30 days with Direct-CPI) for patient using Human Albumin. While phase-II: to assess the impact of Direct-CPI versus NO-CPI on cost saving throughout 10 months duration ( 5 months with NO-CPI and 5 months with Direct-CPI). The number of dispensed vials for each item was recorded by CP. RESULTS: The study findings in phase-I showed that Direct-CPI lead to statistically significant (P < 0.0001) improvement of prescribing for human albumin 20%, especially in cases with albumin level > 3 g/dl, it was 36% with NO-CPI versus 1.6% with Direct-CPI, and in cases with albumin level < 2 g/dl, and it was 6% with NO-CPI versus 42% with Direct-CPI. In phase II, during 5-months of Direct-CPI compared with the same duration of No-CPI, there was a remarkable monthly cost saving, and it was 54% for Human Albumin, 55% for Meropenem and 59% for Ciprofloxacin. This resulted in total cost saving for all three items equal to 123,735 US Dollar during the five months of Direct-CPI.  CONCLUSIONS: Direct-CPI can significantly improve prescribing habit and lead to a substantial cost saving.