The fastest way to heal ulcers under the tongue is to use local medication or systemic medication, as follows. 1. Local medication: the purpose is to anti-inflammatory and analgesic, to promote healing, commonly used drugs are cidadex iodine tablets, watermelon cream powder, dexamethasone ointment and so on. For ulcers with severe pain and delayed healing, submucosal closure of the ulcer can be injected. 2. Systemic medication: the purpose is to prevent secondary infection, reduce recurrence, commonly used drugs are glucocorticoid hormones, such as prednisone, dexamethasone, etc., as well as immune enhancers, such as transfer factor, thymosin, gammaglobulin and so on. All of the above medications should be used under the guidance of a doctor. If the ulcers under the tongue are severe, or if the symptoms persist without improvement, you should go to the hospital in time for treatment.