Psoriasiform eruption and oral ulcerations as adverse effects of topical 5% imiquimod treatment in children: a report of four cases.

Imiquimod 5% cream is a topical immune-response modifier indicated in the treatment of multiple cutaneous conditions including actinic keratoses, superficial basal cell carcinoma, and condylomata acuminata. In children, it has been approved only for ages 12 and older in the treatment of external genital and perianal warts. It has also been used off label for a variety of pediatric skin disorders, including molluscum contagiosum (MC), trichoepitheliomas, verrucae plana, and verrucae vulgaris. Local and systemic adverse reactions have been reported, with the most frequently reported events being application site reactions including itching, burning, erythema, and erosion. Although these local reactions are well known, other rare local and systemic reactions can occur. There have been multiple case reports in adults of rare adverse cutaneous reactions occurring with imiquimod, but few have been reported in children. We present four cases of rare adverse cutaneous reactions. In all cases, the children were being treated with imiquimod 5% cream for verrucae or MC. Two of these patients developed a localized psoriasiform eruption, and two developed mucosal ulcerations.