Flat moss can be treated with oral medication, physical therapy and localized treatment as prescribed by the doctor. 1. Oral medicine: you can take vitamin B, vitamin C, etc.; or oral retinoic acid, isoniazid, etc.; thalidomide treatment of oral lichen planus is more effective, methotrexate for the treatment of warty lichen planus is more effective. 2. Physical therapy: carbon dioxide laser and YAG laser can be used to treat warty hyperplastic lichen planus. 3. Topical treatment: zinc oxide lotion containing menthol or glycerite lotion can be used for acute and extensive cases; retinoic acid can be used for chronic or subacute cases. If you have lichen planus, you should go to a regular hospital in time and choose the appropriate treatment under the guidance of a professional doctor, do not use your own medicine.