Nodule: A small collection of tissue that is palpable (can be felt) at any level of the skin (in the epidermis, dermis, or subcutis) or in another tissue of the body. Nodules characteristically range in size from 1 to 2 cm in diameter. From Healthy Resources How IL Inhibitors Work to Treat PsoriasisModerate to Severe UC: Targeted SolutionsExpert Insight on a New Treatment for C3G Featured Centers What Are the Best PsA Treatments for You?Understanding Biologics 10 Things People With Depression Wish You Knew