Background: Medication errors are common in nursing homes and may result in poisonings and hospitalizations. Objective: This study describes potential drug poisonings in nursing home residents reported to the Danish Poison Information Centre (DPIC), focusing on identifying the reasons of reported potential or occurred poisonings. Methods: A retrospective analysis was conducted on data from the DPIC database covering January 1st, 2014 to October 31st, 2019. Results: We identified 1132 inquiries as potential poisonings in nursing home residents aged 65 years and older, accounting for less than 1% of all inquiries to the DPIC. Drugs were included in 707 inquiries (62%). Of the 707 inquiries, 516 drug poisonings were initially rated as having a limited or no risk (73%), while 146 cases were rated as at risk of life-threatening or manifest poisonings (21%). Hospitalization was recommended in 101 (14%) of 707 cases while the patient was at the nursing home, and in 104 cases (15%) the patient was already in hospital at the time of the call; 38 (37%) of the 104 patients already being hospitalized were rated with a limited or no risk. Most drug poisonings were due to failure in administration processes. Residents ingesting another resident’s medication were seen in 243 cases (34%). Incorrect dosing was seen in 306 cases (43%). Conclusion: Although it is not known to what extent potential poisonings are reported to the DPIC, the data can be used to describe reasons behind medication errors and potential poisonings that occur in nursing homes and thus contribute to the work of preventing medication errors.