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what temp fever to go to hospital

For most people, you should worry less about the exact temperature number and more about how sick the person looks and what other symptoms are happening, but there are clear red-flag temps and signs when you should go to the hospital or ER.

Quick Scoop: When a Fever Needs the ER

Adults

Go to the ER or seek urgent care immediately if an adult has:

  • Fever 103–104°F (39.4–40°C) or higher , especially if it’s not coming down with medicine.
  • Any fever plus:
    • Trouble breathing or chest pain.
    • Confusion, acting strange, or difficulty waking up.
    • Severe headache, stiff neck, or sensitivity to light.
    • Severe abdominal pain, severe muscle pain, or very bad general pain.
    • Repeated vomiting or diarrhea, can’t keep fluids down, or signs of dehydration (very dry mouth, no urine for 8+ hours, very dark urine).
    • Seizure.
  • Fever lasting more than 2 days without improvement, especially if you have heart disease, cancer, are on chemo, are elderly, or have a weak immune system.

If an adult has a lower fever (100–102°F) but looks very unwell , is breathing fast, or is difficult to wake, treat it as an emergency anyway.

Babies under 3 months

This group is extremely high risk.

  • Go straight to the ER/hospital if:
    • Rectal temperature is 100.4°F (38°C) or higher , even once.
  • Do not just watch and wait at home in this age group.

Babies 3–12 months

Go to the ER or urgent care if:

  • Fever 102°F (38.9°C) or higher that lasts more than 1–2 days.
  • Any fever plus:
    • Poor feeding or no wet diapers for 6–8 hours.
    • Trouble breathing, fast breathing, or grunting.
    • Stiff neck, unusual high-pitched cry, or constant inconsolable crying.
    • Rash (especially purple/red spots that don’t fade when you press them).
    • Seizure.
    • Very sleepy, floppy, or hard to wake.

For any child under 3 months , err on the side of going in; for 3–12 months, if you’re unsure, it’s safer to have them seen.

Children over 1 year

Seek ER or urgent care if:

  • Fever 102°F (38.9°C) or higher that:
    • Lasts more than 2 days , or
    • Doesn’t improve with fever reducers, or
    • Keeps coming back high.
  • Any fever plus:
    • Trouble breathing, noisy breathing, or using ribs/neck muscles to breathe.
    • Stiff neck, severe headache, or confusion.
    • Rash that spreads or looks purple/red and does not fade when pressed.
    • Inability to drink or keep fluids down, no urine for 8+ hours, or very dark urine.
    • Seizure or unusual behavior.
    • Severe abdominal pain or they “just don’t look right” to you.

Pediatric hospitals and children’s doctors strongly stress that your gut feeling matters : if your child looks seriously ill to you, go in, even if the number isn’t very high.

What’s “Too High” vs “Can Watch at Home”?

Typical thresholds often used by hospitals and clinics:

  • Adults:
    • Up to 102°F (38.9°C) : often safe to monitor at home if otherwise okay.
    • 103–104°F (39.4–40°C) : call a doctor or urgent care if it doesn’t come down, and go to ER if there are any serious symptoms.
    • Over 104°F (40°C) : seek medical care urgently, especially if it stays that high.
  • Children:
    • Under 3 months: 100.4°F (38°C) = hospital evaluation.
* Over 3 months: **104°F (40°C)** or higher, or 102°F that lasts more than 2 days or with red-flag symptoms, usually needs urgent evaluation.

Remember, how they look and act is as important as the fever number: a child playing, drinking, and waking normally with 102°F is less worrying than a limp, confused child with 101°F.

Safe Home Care (When It’s Mild)

If there are no red-flag symptoms and the fever is below the thresholds above, many doctors recommend:

  • Fluids: water, breast milk/formula, oral rehydration solutions; avoid dehydration.
  • Light clothing and a comfortable room temperature (not ice baths or alcohol rubs).
  • Age-appropriate fever reducers (acetaminophen, ibuprofen for older babies/children), following weight-based doses and not doubling medications.
  • Rest and monitoring: recheck temperature and watch behavior every few hours.

If symptoms change or you feel something is wrong, it’s better to seek help than to wait.

Important: If This Is Happening Right Now

If you or someone near you has:

  • Trouble breathing,
  • Blue/gray lips or face,
  • Chest pain,
  • Seizure,
  • Confusion or can’t wake up,

call your local emergency number now or go to the nearest emergency department.

Information gathered from public forums or data available on the internet and portrayed here.