Swelling of the base of the tongue may be caused by contact with allergens, traumatic edema or tumors of the tongue. 1. Allergy: when the body contact with allergic substances can lead to rapid swelling of the tongue, serious cases can be compressed respiratory tract, need to immediately find out the allergens to stop contact, and take anti-allergy drugs loratadine. 2. Traumatic edema: when traumatized upper and lower teeth accidentally bite together, biting the tongue can also cause swelling of the tongue, including the root of the tongue, general trauma suture to stop bleeding, the swelling will slowly subside. 3. Tumor: when there is a tumor on the floor of the mouth or tongue, it can also cause the swelling of the root of the tongue, after checking in the hospital, surgical resection is needed according to the situation. The root of the tongue is swollen, you need to go to the hospital to do oral examination in order to clarify the cause of the disease.