Fever and convulsions are life-threatening and common causes include febrile convulsions (convulsive seizures due to high fever) and epilepsy. If not timely treatment may induce respiratory blockage dyspnea, and may even induce brain hernia and death. 1. Febrile convulsions: When viral or bacterial infections lead to high body temperature and cause febrile convulsions, if not treated in time, respiratory distress can occur due to respiratory blockage, which is life-threatening. In addition, prolonged high fever can also cause cerebral edema, affecting brain function. 2. Epilepsy: If the patient has a history of epilepsy, fever may trigger seizures, if the seizures continue to cause irreversible damage to the neurons in the brain, causing brain dysfunction, and in severe cases, can lead to cerebral edema, increased cranial pressure, leading to cerebral hernia and death.