Haelan is a medication containing the active ingredient aminolevulinic acid, which is used to treat certain skin conditions like actinic keratosis, a type of skin lesion caused by sun exposure. Haelan works by making the affected skin more sensitive to light, allowing targeted destruction of abnormal cells when exposed to a special light source. This treatment is suitable for individuals with actinic keratosis who need localized therapy for their skin condition.