16 months baby suddenly do not drink milk may be due to physiological factors, such as eating too much complementary food, pacifier hole is too small, etc., or due to pathological factors, such as indigestion, oral ulcers and so on. 1. Physiological factors: (1) eating too much complementary food: 16 months of the baby can add a variety of complementary foods, if the baby ate too much complementary food, occupying the space for milk, can lead to the baby suddenly do not drink milk. (2) nipple hole is too small: if the nipple hole of the bottle is too small, it is difficult to meet the baby’s sucking, which can also lead to the baby suddenly do not drink milk. 2. Pathological factors: (1) indigestion: if parents do not feed properly, it can trigger indigestion, resulting in 16-month-old babies suddenly do not drink milk, and may appear bloating, vomiting and other phenomena. (2) oral ulcers: if the 16-month-old baby suffers from oral ulcers, can be due to the pain of the ulcers when drinking milk, the phenomenon of suddenly do not drink milk, and can be seen in the baby’s mouth with round or oval ulcer surface. 16 months baby suddenly do not drink milk may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.