OBJECTIVES:  The inappropriate uses of hypnotic-sedatives will likely cause drug abuse. It has been known that patients visit different hospitals back and forth to get a duplicate prescription of hypnotic-sedatives. The purpose of this study is to explore the decrease of refill frequency of prescribing sedative-hypnotics and drug cost. METHODS: This is a cohort study. Adult patients, who were prescribed two or more than two sedative-hypnotics with same pharmacological mechanism over a week by different physicians, will be retrieved from the claim database of a medical center in southern Taiwan. The retrieved patients were received a questionnaire to evaluate their knowledge about the appropriate use of hypnotic-sedatives before clinical pharmacists provided patients with education for appropriate use of hypnotic-sedatives. The primary outcome was the reduction of total consumption on  hypnotic-sedatives and drug cost before and after pharmacist education. RESULTS: A total of 100 patients were included in this study. The results showed that about 62.8% of patients with duplicate use of hypnotic-sedatives were female and  59.1% of patients aged ³50 years. Their chief complains was insomnia and/or anxiety which cannot be relieved by taking only one hypnotic-sedatives. The most frequently prescribed drugs in their duplicate prescription were zolpidem (30.45%), Fludiazepam (22.34%), Alprazolam (14.9%), Flunitrazepam(8.45%) and Brotizolam (7.93%) . The average total consumption on hypnotic-sedatives per day for each patient was decreased from 1.68 to 1.33 tablets. The monthly hypnotic-sedatives costs were reduced form NT$ 21,000 to NT $ 15,600. CONCLUSIONS: Pharmacist education on the appropriate use of hypnotic-sedatives and lifestyle management is likely to reduce the total consumption on hypnotic-sedatives and save drug costs.