Topical Anesthetic versus Lidocaine Mixture for Pain Relief During Keloid Treatment: A Prospective, Split Study

BACKGROUND: The most common typical symptoms of keloids can be pain and itchiness. Intralesional corticosteroid administration is generally the first-line conservative treatment. Minimizing pain during intralesional corticosteroid injections into keloids should be aimed, as the treatment is often painful. There has yet to be a report on which local anesthetic technique is superior in keloid treatment between topical anesthetic versus lidocaine mixture injection. METHODS: This was a single-center prospective study. The study included 100 patients with painful multiple/multifocal keloids aged 18 to 85 years and was performed between May 2021 and December 2022. Among multiple keloid lesions in a single patient, we assigned the keloids pretreated with topical cream application versus local injection. Then, subjects received 40 mg of intralesional corticosteroid injections into the keloids with a 26G needle to treat keloids. Patients rated the pain intensity of each lesion pretreated with two different anesthetic techniques on an 11-point numeric rating scale. A separate direct question of "Which technique would you recommend if you had to be injected again?" was given. RESULTS: One-hundred patients with painful multiple/multifocal keloids were included in the study. Data on pain intensity numeric rating scale (NRS) revealed that injection techniques relieved the pain statistically significantly more than topical creams. ( P <0.001) 63% of the participants (n=63) preferred the injection technique, while 25% preferred topical anesthetics. In total, 12% of patients responded that there was no difference between the two techniques. CONCLUSION: When comparing with topical lidocaine/prilocaine (EMLA) cream, a 1:1 mixture of 1% lidocaine and epinephrine significantly alleviated pain during and after the corticosteroid injection.