Background/Aim. Prescription of drugs is a fundamental care component of the elderly. Elderly patients often take multiple drugs, and it is known that polypharmacy may lead to drug interactions and adverse events. The aim of this study was to analyze the long-term drug use and the prevalence of polypharmacy among the elderly population in the Republic of Srpska, Bosnia and Herzegovina. Methods. A retrospective study of outpatient drug use in 2005 and 2010 was conducted, analyzing prescriptions for patients aged ≥ 65 years reimbursed by the Health Insurance Fund. The study population was stratified by gender and age. Long-term drug use was defined as continuous drug dispensing for a whole year or at least two thirds of the year. Polypharmacy was defined as the use of 5 or more different reimbursed drugs. Results. Of all insured people aged ≥ 65 years, long-term drug use was identified in 10% (2005) and in 19% (2010), of whom 62% were women. Two to four different drugs were used by almost 49% (2005) and 54% (2010) of the elderly patients. The polypharmacy prevalence increased from 1.4% (2005) to 3.6% (2010); it increased in all the age groups of both genders. The largest increase was observed in the age group 65-74 years. Polypharmacy prevalence increase was higher in women. The most commonly used drugs were those for to treatment of cardiovascular diseases, in particular drugs for hypertension and cardiac treatment. Conclusion. The study findings point out to the increase of elderly population with a long-term drug use. Over a half of elderly patients use 2-4 different drugs on the long-term basis. The polypharmacy prevalence was low. It increased in the period of 5 years in both genders. The increase was more prominent in women of all the age groups. The use of multiple drugs and polypharmacy increased with ageing.