The number of aesthetic medicine procedures performed is increasing year on year. Among the most common procedures are those involving tissue fillers. Despite their high safety profile, it is essential to consider that these procedures may be associated with adverse reactions. This paper describes the cases of two patients, who have experienced delayed adverse reactions in the form of persistent lumps, after the administration of poly-D,L-lactic acid in the tear trough area. Due to the lack of an established etiology for these occurrences, a standardized treatment has not been described to date. Further research on the safety of using poly-D,L-lactic acid in the tear trough area as well as into the effective treatment of any adverse reactions after its application is necessary.