Flat warts are usually caused by viral infections. Flat warts on the hands can be removed by medication, laser removal, cryotherapy and so on. 1. medication: patients can follow the doctor’s instructions to use topical medication, such as retinoic acid cream, tazarotene gel, and so on. You can also take thymidine enteric-coated tablets, transfer factor capsules and other drugs to improve the body’s immunity. 2. laser removal: if the use of drugs is not obvious, flat warts area is relatively large, the patient can follow the doctor’s instructions to take carbon dioxide laser burning and other ways to remove. 3. Freezing therapy: the patient can also use the freezing technique to remove, through the liquid nitrogen to the affected area for freezing, so that the flat warts warts necrosis off. As flat warts are contagious, if you scratch them, they will grow in the direction of the scratches. Patients should try to minimize irritation and use sterilized cotton pads or washcloths when washing their faces to avoid cross-infection. In addition, they should pay attention to hygiene and hand cleaning in normal times, and avoid eating spicy, stimulating and greasy food. It is recommended that patients go to the hospital in a timely manner, standardize treatment under the guidance of the doctor, and all medications must be used in accordance with the doctor’s instructions.