Convulsions after fever may be caused by the following factors: 1. febrile convulsions: Most commonly seen in children aged 6 months to 6 years, due to the imperfect development of the child’s nervous system, the rapid rise in body temperature will lead to abnormal discharge of the child’s brain cells, so there are convulsions, the convulsions will last for ten seconds or a few minutes, the longest time will not exceed 15 minutes, there will be no sequelae after the convulsion. 2. Central nervous system infection: It may also be caused by encephalitis, meningitis and other central nervous system infectious diseases, intracranial inflammation will lead to increased intracranial pressure, so the patient will have fever and convulsions. 3. Toxic encephalopathy: Severe infections can cause toxic encephalopathy, which can be recovered after dealing with the original disease and will not leave sequelae. 4. Seizures.