Your baby is mid-teething — drooling, gnawing, miserable — and now the thermometer is showing a fever. The internet told you teething causes fevers, so maybe this is just teeth? Here's the honest, important answer: a true fever is never just teething. Teething can nudge a temperature up a little, but a real fever is a separate illness that deserves its own attention.
This is one of the most common — and highest-stakes — teething myths, so let's get it exactly right, calmly.
What the science says
Real teething symptoms cluster in the few days around a tooth breaking through: drooling, chewing, sore swollen gums, and crankiness. The temperature piece is where parents get misled. Per the American Academy of Pediatrics and the NHS, teething may cause a slightly raised temperature — but slightly is the operative word.
Teething does not cause a true fever. A temperature of 100.4°F (38°C) or higher is a real fever from something else — most often a run-of-the-mill virus that happened to show up the same week as a tooth. The reason these overlap so often is simple: babies who are teething put everything in their mouths, which is exactly how they pick up the viruses going around. So a tooth and a cold genuinely do arrive together a lot — but the cold is doing the fever, not the tooth.
The practical rule: if the reading is 100.4°F or higher, treat it as illness, not teething. Don't write it off. Our full teething timeline and relief guide covers everything teething does and doesn't cause, and the newborn fever guide explains how to read a fever by age.
Why this myth is worth correcting
Blaming a fever on teething feels reassuring at 2 a.m. — it's a tidy explanation that means you don't have to do anything. But that's exactly the trap. A true fever can be the body's response to a genuine infection, and in young babies especially, a fever can be the only outward clue that something needs evaluating.
Teething also does not cause diarrhea, a runny nose, a cough, a rash, or vomiting. Those, like a true fever, are signs of illness. So if your teething baby also has a fever plus any of those, that's a sick baby with a tooth coming in — two things at once — and the illness is what you respond to.
What helps a baby who's teething and sick
When both are happening, comfort measures overlap nicely:
- For sore gums: a clean finger or damp gauze rubbed on the gum, a chilled (not frozen) teething ring, or a cold washcloth.
- For the fever and discomfort: the right weight-based dose of acetaminophen, or ibuprofen for babies over 6 months — dose by weight, not age, and never aspirin. See our infant medication dosing guide, or ask your pediatrician or pharmacist.
- Fluids: keep breast or bottle feeds going on demand; a fever raises fluid needs.
Skip the benzocaine gels, homeopathic teething tablets, and amber necklaces the FDA warns about — none of that touches a fever anyway.
When to call your pediatrician
A fever during teething is a reason to look at the fever on its own terms. Call — and treat it as illness, not teeth — using these thresholds, drawn from AAP guidance:
- Any rectal temperature of 100.4°F (38°C) or higher in a baby under 3 months is a medical emergency — call your doctor or go to the ER immediately, even if your baby looks fine. This rule has no exceptions.
- For older babies, call if the fever repeatedly tops 104°F (40°C), lasts more than 24 hours in a child under 2, or your baby still "acts sick" once it's down.
- Diarrhea, vomiting, a rash, a persistent cough or runny nose, or a baby who seems genuinely unwell — none of these are teething, so look for the illness.
- Signs of dehydration: far fewer wet diapers, no tears, a dry mouth.
Logging the temperature, the time, and any medicine in the TinyWins app means that when you call the nurse line, you can say exactly when the fever started instead of guessing.
The bottom line
A slightly raised temperature can come with teething — a true fever cannot. Anything 100.4°F (38°C) or higher is a real fever from another cause, and the safest move is always to treat it as illness rather than blame the tooth. When teething and a virus overlap (which they often do), comfort the gums and respond to the fever by the rules for your baby's age — and never forget the one that's absolute: 100.4°F under 3 months means call now.
This article is educational and not medical advice. Always check with your pediatrician/provider.