Recently, the number of elderly people who take medicines daily has been increasing due to the aging population. Because elderly persons tend to experience cognitive deterioration, some may have difficulties in complying with their medication regimens. Therefore, we propose a new fuzzy-based inference algorithm to assist caregivers by providing them with remote monitoring capabilities. In this study, we developed an intelligent living environment with radio frequency identification (RFID) readers to detect when a person inappropriately self-administer medications with meals or drinks, for which coadministration is contraindicated and would decrease beneficial effects of the medicines or produce serious adverse effects. In the laboratory, RFID readers were strategically placed in a novel intelligent medicine case and around the kitchen. The readers recognized RFID tags affixed on objects such as medicines, foods, beverages, and drinking vessels. A wireless device with flow sensors was also placed in the kitchen unit to measure tap water consumption. Our experiments confirmed that based on the proposed algorithm, the system was able to recognize the presence of objects and usage of tap water, and to detect a typical contraindicated coadministration of a medication with a particular food product. The results indicate the potential of the system to directly alert caregivers by using the intelligent medicine case, in order to prevent inappropriate medication administration.