Medically reviewed
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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K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
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