The baby’s drowsiness and lack of spirit after the fever is gone may be physiological factors, usually no need to deal with, but it may also be meningitis, encephalitis, etc., and it is recommended to take medication, surgical treatment, and so on. 1. Normal physiological factors: the baby will have more physical exertion during the fever, after the fever is gone, there will be drowsiness and lack of spirit, if the baby is not accompanied by other uncomfortable symptoms, such as irritability, crying and restlessness, etc., you can continue to observe, usually without special treatment. 2. Meningitis: may be caused by viral or bacterial infections, may appear after the fever goes down, drowsiness, no spirit phenomenon, accompanied by neck straightening. If caused by viral infection, symptomatic supportive treatment can be taken, and if accompanied by hydrocephalus, cerebrospinal fluid drainage can be taken. Bacterial infection can take ceftriaxone, cefotaxime and other treatments. 3. Encephalitis: Mostly caused by viral infection, drowsiness, malaise, fever, severe headache, nausea, vomiting and other symptoms can occur. It can be treated with antiviral infections such as acyclovir under doctor’s guidance. Parents also need to give the baby more plain water to replenish the water needed by the body to avoid causing dehydration or electrolyte disorders. If your baby is not feeling well after the fever goes down, please go to the hospital to avoid delay.