Six-month-old babies biting the lower lip may be caused by hunger, nervousness, perioral eczema, etc. General treatment, medication, etc. are needed depending on the cause. 1. Hunger: If the baby is hungry, he may bite his lower lip involuntarily, and may also cry and be restless. It is recommended to go to breastfeed the baby in time to replenish the needed nutrients, and it will usually get better. 2. Nervousness: Babies may also bite their lower lip if they are nervous or anxious. As the baby’s feeding may not be satisfied, the need to calm the baby or distract the baby’s attention can improve the situation. 3. Perioral eczema: If suffering from perioral eczema, erythromycin ointment, etc. can be applied under the guidance of a doctor. If your baby is suffering from unsatisfied mouthing, you can use a pacifier. Six-month-old baby biting the lower lip may also be related to other reasons, if the phenomenon of frequent unrelieved or also accompanied by other abnormalities, it is recommended to consult a doctor in order to clarify the cause of the disease, standardized treatment.