Introduction - Arctium lappa (Lappa) is used in traditional Western and Chinese medicine for acne. It is mentioned in homeopathic literature for acne, but its effect has not previously been evaluated.Objective - To determine the effectiveness of homeopathic medicine Lappa in treatment of acne vulgaris.Methods - An uncontrolled observational interventional study was conducted on human subjects who fulfilled the inclusion criteria and gave written informed consent. Lappa was prescribed in potencies starting from 6c rising to 1M as required, over a period of 6 months. Objective assessment was change in acne lesion counts supplemented with Global Acne Grading System (GAGS) and subjective assessment by using Acne-Specific Quality of Life questionnaire (Acne-QoL).Results - Out of 34 human subjects, 32 completed the follow-up. Statistical significant results were seen in lesion counts, GAGS and Acne-QoL score (p value <0.001).Conclusion - Lappa has shown positive effects in the treatment of acne especially of inflammatory type. Further controlled, randomized studies with larger sample size are desirable.