OBJECTIVE: Evaluation of drug expenditure and consumption during year 2001. METHODS: A retrospective study was done by statistical evaluation of drug files in Drug Administration archives. RESULTS: In 2001, an estimate of 19.77 billion numbers drug equal to 4132 billion Rials has been sold in Iran. Comparing the year 2000, the average increase of 5.7% in drug numbers and 22.3% in costs was reported. We have to add 241 billion rials that are subsidized by government on mentioned amount. These data show that each Iranian used more than 304 number drugs equal 63584 Rials in 2001. Analgesics, Anti Infectious and Gastrointestinal drugs were the most common used drugs in 2001 respectively. In this regard Acetaminophen-Codeine (500-8mg, tab), Acetaminophen (325mg, tab), Amoxycillin (500 mg, cap), Adult Cold; Ranitidine (150 mg, tab), Glibenclamid (5mg, tab), Ferrus sulfate (50 mg, tab) and ASA (100mg, tab) are the first 10th drugs that have been sold in 2001. Concerning drug expenditure according to therapeutic class, CNS drugs, Anti Infectious and Gastrointestinal drugs with 6.694, 2.754, and 2.370 billion numbers were the most common sold drugs. CONCLUSIONS: Since the present data have been derived from wholesalers thus it is possible that some drugs have not been used by patients and some might be smuggled. Further studies should be undertaken to determine the relationship between rates of different therapeutic drugs sold and incidence of related diseases in our country.