The topical medications for flat warts include retinoic acid ointment, fluorouracil ointment, 5% imiquimod cream and so on. 1. Vitamin A ointment: mainly through the regulation of cellular immunity and the proliferation of epithelial cells to achieve the therapeutic purpose. The main adverse reactions include allergy, edema and so on. It is contraindicated in patients with lactation and allergy. 2. Fluorouracil ointment: it can leave hyperpigmentation after use, and should be used with caution on the face. Adverse reactions also include nausea, loss of appetite. It is contraindicated in patients with allergy, early pregnancy and lactation. 3.5% imiquimod cream: mainly through the activation of immune cells to stimulate the body to recognize the virus to achieve the therapeutic purpose. It is suitable for the treatment of mild to moderate flat warts. Adverse reactions include localized itching, tingling, erythema and so on. It is contraindicated in patients with allergy, hypersensitivity, early pregnancy and lactation. The appearance of flat warts is recommended to consult a doctor in time, the use of specific drugs should be carried out under the guidance of a doctor, if necessary, can be combined with freezing, laser treatment.