Mesotherapy is a medical technique that administers cosmetic nutrients directly to the dermis through microdrop injections for aesthetic purposes. Its application has become increasingly widespread. However, there have also been a growing number of reported cases of multiple foreign body granulomas following mesotherapy. It is crucial to find an effective and safe treatment. In this study, 31 patients with facial foreign body granuloma after mesotherapy were included. A mixture of 5-fluorouracil, lidocaine injection , and normal saline was prepared in a ratio of 1:1:4 and injected subcutaneously. Triamcinolone acetonide, 5-fluorouracil, lidocaine injection, and normal saline were prepared in a ratio of 2:5:3:10. Subcutaneous injections were administered to each papule using a 34G needle. The treatments were scheduled at intervals of 10-14 days. Color Doppler ultrasound was used to evaluate the condition before the initial treatment and after the final treatment. The preoperative ultrasonography revealed diffuse hypoechoic areas in the dermis of the facial skin. After an average of 2-4 treatment sessions, a significant improvement was observed in all patients' appearance, with reduced redness and swelling, softened nodules, absence of pain and itching symptoms, and no evident abnormal echo on ultrasound examination. During a follow-up period ranging from 1 to 8 months, no recurrence or adverse reactions were reported. This technique demonstrates clear efficacy. And this formulation effectively reduces the dosage of triamcinolone acetonide and minimizes the risk of adverse reactions such as skin atrophy. Therefore, it can be considered an effective treatment for multiple foreign body granulomas following mesotherapy. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .