The aim of this study was to determine the number of potentially inappropriate medications (PIMs) among elderly patients in the database of spontaneously reported adverse drug reactions (ADRs) given by the Agency for Medicinal Products and Medical Devices. A comprehensive protocol was used with the aim to determine the causal connection between PIMs and spontaneously reported ADRs. The retrospective observational study included patients aged 65 years and older whose ADRs were reported to the Agency for Medicinal Products and Medical Devices of Croatia during the period from Jan 9, 2013 to Dec 20, 2013. Potentially inappropriate medications were determined by using a comprehensive Croatian protocol. As a reference source for determining the causal connection between the reported ADR and identified PIMs, the Summary of Product Characteristics (SPC) was used, whereas the Clinical Support Decision System, Lexicomp was used for determining the consequences of potentially inappropriate interactions. The study included 50 patients ( age of 73,48 ± 6,08) with an average number of diagnoses of 2,72 ± 0,99. On average, the patients used 3,82 ± 0,98 medications and experienced 2,42 ± 1,53 ADRs. According to the Comprehensive protocol, 36% of patients used at least one potentially inappropriate medication. The most prevalent potentially inappropriate medications were the long-acting benzodiazepine diazepam and the centrally acting antihypertensive moxonidine, while the most prevalent drug interaction was the combination of NSAID with an antihypertensive drug. The analysis of the entire sample shows that 16,5% of total ADRs report were caused by PIMs which leads to the conclusion that the PIM use is not associated with more ADRs reports than any other medication not classified in this way. None of the side effects classified as serious were actually a result of the application of a potentially inappropriate drug. Despite the lower percentage of potentially inappropriate drugs in our sample, we believe that the using a Croatian comprehensive protocol for the detection of potentially inappropriate medication can result in more rational application of medicines and improve the health care of patients which can ultimately result in better compliance of patients and greater confidence in the health system.