Refractory Subacute Cutaneous Lupus Erythematosus Resolved by Identifying an Unconventional Trigger: A Case of Cannabis-Induced Exacerbation

Subacute cutaneous lupus erythematosus (SCLE) is an autoimmune condition marked by nonscarring, photosensitive lesions on sun-exposed areas. Cigarette smoking is known to exacerbate cutaneous lupus through inflammatory and immunomodulatory pathways; however, the impact of cannabis smoke is not well characterized. We present a case of a 45-year-old woman with systemic lupus erythematosus and SCLE whose cutaneous disease had been refractory to multiple immunomodulatory and immunosuppressive therapies. After prolonged treatment failure, further social history revealed prolific cannabis smoking. Following the transition from smoked to edible and vaporized cannabis, the patient entered sustained remission of her skin lesions. This case suggests that inhaled cannabis smoke may share pathogenic mechanisms with tobacco smoke and contribute to disease activity through common toxins, including aromatic amines and polycyclic aromatic hydrocarbons. The case also highlights the importance of facilitating open communication about social and smoking history, as well as educating patients on how these factors can influence disease activity. Incorporating tobacco cessation recommendations along with harm reduction strategies, such as recommending nonsmoked cannabis formulations, offers a practical, patient-centered approach to managing SCLE flares, particularly in cases unresponsive to standard therapy.