The CDC considers a person to have a fever when he or she has measured temperature of 100.4°F (38°C).

Mild or moderate states of fever (up to 105 °F [40.55 °C]) cause weakness or exhaustion but are not in themselves a serious threat to health. More serious fevers, in which body temperature rises to 108 °F (42.22 °C) or more, can result in convulsions and death.

Outlook for hyperpyrexia? Hyperpyrexia, or fever of 106°F or higher, is a medical emergency. If the fever is not lowered, organ damage and death can result. In fact, if you’re experiencing a fever of 103°F or higher with other significant symptoms, it’s important that you seek immediate medical care.

Once a fever goes beyond the high level, an adult enters dangerous fever levels (104 F – 107 F). Once a fever reaches the dangerous level, also known as hyperpyrexia, it is a medical emergency and you should seek medical care immediately.

Viruses that can cause hyperpyrexia include enterovirus infection, roseola, rubeola, and malaria. Hyperpyrexia is associated with a body temperature of more than 106.7°F or 41.5°C. Typically, treatment for hyperpyrexia focusses on the underlying disease, if one exists.

Get Treatment for High Fever at Dignity Health Acetaminophen (Tylenol) and nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, Motrin), are options. Your doctor will treat any underlying infection if necessary.

How to break a fever

1. Take your temperature and assess your symptoms.
2. Stay in bed and rest.
3. Keep hydrated.
4. Take over-the-counter medications like acetaminophen and ibuprofen to reduce fever.
5. Stay cool.
6. Take tepid baths or using cold compresses to make you more comfortable.