Ingenol mebutate was previously used in dermatology for the treatment of actinic keratosis, a precancerous skin condition caused by prolonged sun exposure. Applied topically to affected areas, it worked by inducing cell death in abnormal skin cells and promoting an immune response to clear damaged tissue. The treatment was short, typically lasting a few days, and its localized action minimized systemic side effects, though common local reactions included redness, swelling, and itching. Valued for its efficacy in reducing skin cancer risk and ease of use, it was marketed as Picato gel. However, due to post-marketing studies indicating a potential increased risk of skin cancer (e.g., squamous cell carcinoma), the product was voluntarily withdrawn from the market worldwide in 2019 and is no longer available for clinical use. It may still be available for research purposes.