A fever of 38.5 degrees overnight is usually not dangerous. However, it is important to pay attention to whether the temperature has continued to rise, and whether there is any high fever, convulsions (seizures) or epileptic conditions. It is also important to actively identify the cause of the illness and treat the cause to relieve the fever. Most fevers are caused by upper respiratory tract infections, influenza, pneumonia and other diseases. Fever is usually recurrent and is usually not dangerous as long as it is treated properly. The following situations are still dangerous and need to be dealt with in time: high fever, convulsions: the patient may have a complete loss of consciousness, eyes staring, squinting or upturned, head tilting, convulsions, respiratory arrest and even bruising and other clinical manifestations. Epilepsy may appear involuntary twitching and spasm in the whole body, localized, and may also have symptoms such as impaired consciousness. Patients with a fever of 38.5 degrees can be treated with physical cooling or medications such as ibuprofen and acetaminophen. In general, a fever of 38.5 degrees overnight is not dangerous if there are no abnormalities or if the temperature continues to rise. If medication is needed, it should be used under a doctor’s supervision.