A fever is the body’s normal response to an infection, and most fevers pass in a few days without a doctor. The number on the thermometer matters, but so do the person’s age, how long the fever has lasted, and how sick they look. A 101°F fever in a healthy adult who is drinking fluids is a different situation from the same reading in a six week old baby.
When to go to urgent care for fever
For adults, get seen if your temperature climbs above 103°F (39.4°C), stays high, or lasts longer than two to three days. For children 2 and older, a fever lasting more than three days is the usual cue. For children under 2, the window is shorter: more than 24 hours. Any fever in a baby younger than 3 months is an emergency room visit, not an urgent care visit.
Those thresholds come from Cleveland Clinic’s guide to fever, the National Library of Medicine’s MedlinePlus page on fever, and the American Academy of Pediatrics’ HealthyChildren guidance on when to call about a fever. How a person looks and acts can override every number in this article. A child who is limp, hard to wake, or struggling to breathe needs emergency care even with a modest temperature.
What counts as a fever
Cleveland Clinic says providers most often call 100.4°F (38°C) measured by mouth a fever in adults. In children, MedlinePlus lists 100.4°F (38°C) taken rectally, 99.5°F (37.5°C) by mouth, or 99°F (37.2°C) under the arm. The method matters most in babies, where a rectal reading is the accurate one. Norton Children’s notes that forehead strips, ear thermometers, and pacifier thermometers are not considered accurate for infants under 3 months.
Fever often comes with chills, sweating, body aches, headache, and a poor appetite. When an infection causes it, Cleveland Clinic says a fever typically passes in three to four days.
Fever temperature thresholds by age
This table pulls together the cutoffs from the sources above. Use it as a guide, and trust your instincts if someone seems sicker than the number suggests.
| Age | Get seen at urgent care or call your provider | Go to the ER |
|---|---|---|
| Under 3 months | Not an urgent care situation | Any rectal temperature of 100.4°F (38°C) or higher |
| 3 to 12 months | Fever of 102.2°F (39°C) or higher, or a fever lasting more than 24 hours | Hard to wake, trouble breathing, will not feed, or any emergency sign below |
| 1 to 2 years | Fever lasting more than 24 hours | Any emergency sign below |
| 2 years and older | Fever lasting more than 3 days (72 hours), or rising above 104°F (40°C) repeatedly | Any emergency sign below |
| Adults | Above 103°F (39.4°C), or lasting longer than 48 to 72 hours | Fever with a stiff neck, confusion, trouble breathing, or a seizure |
Fevers that come and go for a week or more also deserve a visit, even if they never get very high, according to MedlinePlus.
Why babies under 3 months go straight to the ER
Norton Children’s advises parents to seek immediate treatment at an emergency department for a rectal temperature of 100.4°F or higher in a baby under 3 months, and not to wait and see whether it goes away. A newborn’s immune system is still developing, and a fever can be the only sign of a serious infection. Cleveland Clinic gives the same advice.
How long can a fever last before a visit?
So when should you go to urgent care for a fever that is not especially high? Count the days. Adults should be seen after two to three days of fever. Children under 2 should be seen after 24 hours, and children 2 and older after three days.
Also get checked sooner if the fever breaks and then returns, if a child still seems sick after the fever comes down, or if new symptoms show up, such as ear pain, a painful sore throat, burning with urination, or a cough that is getting worse. Those patterns can point to a bacterial infection that may need treatment.
People with heart problems, a weakened immune system, or who take steroids or other medicines that affect immunity should call their provider earlier, according to HealthyChildren.
What happens at an urgent care visit for a fever
The provider checks your temperature, heart rate, and breathing, asks how long the fever has lasted, and examines the ears, throat, chest, and belly to look for the source. Often the cause is a virus that just needs time. When a test would change the plan, it helps to have it done in the same building.
LoneStar has a lab and X ray on site. The diagnostic services offered at LoneStar include rapid flu and strep testing, urinalysis, and blood tests such as a complete blood count, so a fever caused by strep throat or a urinary tract infection can be found during the same visit. If the flu is the likely cause, the clinic’s page on flu testing and treatment explains what to expect.
At home, rest and fluids help, and fever reducing medicine can make someone more comfortable when used exactly as the label or your provider directs. Cleveland Clinic notes that fevers below 103°F are usually not dangerous in adults. Do not give aspirin to children.
When a fever needs the ER or 911
The temperature alone does not decide this. MedlinePlus says to call 911 if a person has a fever and any of the following:
- Cannot be woken easily, or seems confused
- Has trouble breathing, even after the nose is cleared, or has blue lips, tongue, or nails
- Has a very bad headache or a stiff neck
- Has a seizure
- Cannot walk, or a child refuses to move an arm or leg
- A child is crying and cannot be calmed
Cleveland Clinic adds abdominal pain, repeated vomiting, and a new rash with fever as reasons to go to the emergency room. In South Texas, also think about heat. HealthyChildren lists a child who has been in a very hot place, such as an overheated car, as a reason to call right away. If someone is hot, confused, or hard to wake after time in the heat, call 911.
Get seen for a fever at LoneStar Urgent Care
If you are unsure when to go to urgent care for fever symptoms that are dragging on, walking in is the simplest way to get an answer. LoneStar Urgent Care has two walk in clinics on the Southside of Corpus Christi: Rodd Field Road at 1702 Rodd Field Rd, Suite 105, and Weber Road at 6409 Weber Road. Both are open Monday through Saturday from 8 AM to 8 PM and Sunday from 10 AM to 6 PM, and no appointment is needed.
You can check in online and wait at home until a text tells you the provider is ready. The clinic accepts most major insurance plans and Medicare, and the self pay visit price is $115.
This article is for general information and does not replace advice from your own medical provider. If you think you are having a medical emergency, call 911.