The treatment of pathological scar has always been a research hot topic for plastic surgeons, but no effective treatment has been found so far. There are many kinds of invasive treatment and noninvasive treatment for pathological scar, but they all have high recurrence rate.Therefore, local injection therapy with less trauma and simple operation is more popular. Through reading the literature, we found that the commonly used drugs in the injection treatment of pathological scar are botulinum toxin type A, corticosteroids, verapamil, 5-FU. However, theclinical studies of these four drugs in the treatment ofpathological scar are mostly randomized controlled studiesof the clinical efficacy of two or three of them. Thesestudies included fewer patients. Therefore, the conclusionsof the study cannot comprehensively and systematicallyguide plastic surgeons in the choice of drugs in the treatmentof pathological scars by injection. For the above