Case report: lichen planus in a patient with ulcerative colitis receiving sulfasalazine: a drug effect or a disease manifestation?

Lichen Planus is an inflammatory skin disease that has been reported to be associated with inflammatory diseases like Inflammatory Bowel Disease or with medication use such as sulfasalazine. We report a case of lichen planus in a 62-year-old patient with ulcerative colitis receiving sulfasalazine. Within three years of treatment, the patient developed an erythematous rash on her forehead and wrists, which gradually worsened and spread to her arms, forearms, neck, and upper back. Lichen planus was suspected and later confirmed through histopathological examination. Consequently, sulfasalazine was discontinued, leading to partial resolution of the skin lesions. Our case highlights the importance of a thorough patient interview, as the timeline of skin lesions in relation to medication use and disease activity.