Keloids are defined as the formation of collagen-rich scar tissue extending beyond the original lesion. Not all keloids respond to conventional treatment with intralesional triamcinolone injections. Recurrence of keloids after primary excision is reported in almost 100% of cases and should therefore always be followed by adjuvant treatment. Currently, consensus on preferred adjuvant treatment in relation to keloid excision is lacking. This study seeks to systematically review evidence on the efficacy of adjuvant treatments in relation to keloid excision. A systematic literature review was conducted on PubMed. Titles, abstracts, and articles were screened and sorted according to defined inclusion- and exclusion criteria. Each study was evaluated according to the Oxford Centre for Evidence-Based Medicine, OCEBM, Levels of Evidence by two independent authors. Seven studies were eligible. Adjuvant treatment methods included intralesional triamcinolone injection, radiotherapy, silicone gel, pressure therapy, verapamil hydrochloride and 5-fluorouracil. While all the included studies reported promising results, two studies showed that minimizing dosages when treating with radiotherapy or triamcinolone should be considered to avoid adverse events. However, a high risk of bias was found in all the included studies.