For most adults, having a temperature above 100.4°F is considered a fever. Most fevers can be managed at home and will start to improve within several days. Still, knowing when to speak with a medical provider for a fever can help you get the care you need and avoid complications.
If you have a fever that won’t go down after several days of rest, have a temperature of 103°F or higher, or experience severe symptoms such as chest pain or difficulty breathing, it’s best to talk to your provider. Read on to learn more.
When to See a Doctor for Fever
Mild fevers can be treated at home. For fevers of 103°F or higher, adults should contact their medical provider or seek emergency care.
Additional symptoms that warrant more immediate medical attention are:
- A fever that does not improve after three days of rest and home care
- Severe headache
- Severe throat swelling
- Unusual skin rash
- Sensitivity to bright light
- Stiff neck (or pain when you bend your head forward)
- Mental confusion
- Persistent vomiting
- Difficulty breathing
- Chest pain
- Abdominal pain
- Pain when urinating
- Extreme fatigue
- Extreme irritability
- Muscle weakness
- Sensory changes
- Seizure
See a doctor online.
Start my visitWhat’s Considered a Fever?
One factor that helps distinguish a fever from normal variations in body temperature is age.
Infant
Any elevated temperature in an infant or child younger than three months old is considered a fever.
Children
A child’s temperature can be read using different types of thermometers. The below temperatures are considered a fever in children three months and older:
- 100°F via oral thermometer
- 100.4°F via rectal thermometer
- 99°F axillary temperature (taken in the armpit)
Adults
Any temperature above 100.4°F is considered a fever in adults.
Common Fever Causes
A fever can be a sign of many conditions. Some of the most common causes of a fever include:
- A viral or bacterial infection
- Medicines (including antibiotics and blood pressure and anti-seizure medications)
- Heat illness
- Cancer
- Autoimmune disease
- Some vaccines
Additional Possible Symptoms
A fever is a symptom of a condition, rather than an illness itself. Depending on the type of illness you have, you may experience other symptoms such as:
- Chills
- Fatigue
- Body aches
- Loss of appetite
- Dehydration
- Irritability
Medical Treatment
Many fevers can be treated at home with rest, fluids, and over-the-counter (OTC) pain relievers. If you need to seek treatment from a medical provider, depending on the underlying cause of your fever, they might recommend one of the following treatments:
- Antibiotics or antivirals
- Other prescription medications
- Intravenous medications
- Fluid replacement
See a doctor online.
Start my visitFever Risks
Dehydration is a common risk of a fever. That’s why it’s important to rest and stay hydrated by drinking plenty of non-caffeinated liquids (such as water, herbal tea, and electrolyte-based fluids) when you have a fever.
Additional risks are possible in people with certain medical conditions, including diabetes and cancer. If you’re immunocompromised and have a fever, contact your medical provider for guidance.
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Frequently Asked Questions
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