Infections and allergic reactions are two problems to expect from this piercing. If a muscle has been pierced, if the tongue rejects the metal, if bacterial infection occurs where the tongue has much bacterial activity occurring or food has lodged in the cavity of the piercing, there will be an aggravated reaction until the pierced hole is closed. Sometimes antibiotics are necessary continuously. The chipping of teeth is frequent because of the ring clinking from continuous tongue movement. The change in taste of foods occurs as well because of the metal chemically changing taste buds on the tongue. The possibility of infection by unclean needles and careless piercing is common. A negative list of what could occur goes on. Swelling is one start of problems with tongue piercing. Have the piercing seen by a medical care staff member for diagnosis of what is occurring.