The baby always drooling is caused by a variety of reasons: 1, the baby’s swallowing function is not yet sound, saliva will not swallow in time, so it will flow out, this is a normal phenomenon, with the growth of age, the symptoms will slowly improve. 2, the baby is almost teething, when the teeth will soon grow out, the gums will be very itchy, will stimulate the nerves in the mouth, so there will be a lot of drooling. This is also a normal phenomenon, no need to pay special attention. 3, pathological factors caused by inflammation, herpes, ulcers in the mouth, there will also be drooling situation. This situation should promptly go to the hospital, under the guidance of doctors, symptomatic treatment. 4, may be caused by a lack of trace elements, to check the trace elements, according to the results of the corresponding supplement.