Does Teething Really Cause Fever?
The short answer
Research shows that teething may cause a slight increase in body temperature, but it does NOT cause true fever (temperature at or above 100.4 degrees F / 38 degrees C). A large systematic review of studies found that teething may cause temperatures up to about 100 degrees F (37.8 degrees C), along with drooling, gum irritation, and fussiness. If your baby has a temperature of 100.4 degrees F or higher, they likely have an illness that coincidentally timed with teething, and the fever should be evaluated by your pediatrician rather than dismissed as "just teething."
By Age
What to expect by age
Teething typically begins around 6 months - the same age when maternal antibodies begin to wane and babies start getting more infections. This overlap is why teething is often blamed for fevers that are actually caused by illnesses. True teething symptoms include: drooling, gnawing and chewing on objects, mild gum irritation, slight fussiness, and possibly a very slight temperature elevation (but below 100.4 degrees F). Symptoms that are NOT caused by teething include: fever above 100.4 degrees F, diarrhea, rash on the body, congestion, and cough. These indicate illness and should be evaluated.
Toddlers continue to get new teeth through age 3 (molars and canines), and parents may attribute various symptoms to teething. Evidence-based teething symptoms are limited to: gum discomfort, drooling, irritability, and desire to chew. If your toddler has a fever over 100.4 degrees F during teething, look for other causes. Common illnesses in toddlers (ear infections, viral infections, roseola) frequently coincide with teething simply because children are teething for much of their first 3 years. Attributing a fever to teething can delay diagnosis and treatment of actual illness.
What Should You Do?
When to take action
- Drooling and wanting to chew on things during teething
- Mild fussiness around the time teeth are erupting
- A very slight temperature elevation below 100.4 degrees F
- Swollen, tender gums where a tooth is about to emerge
- You are unsure if symptoms are from teething or illness
- Your baby has a temperature at or above 100.4 degrees F and you have been told it is "just teething" - it is worth confirming
- Teething pain seems severe and you want guidance on pain relief
- Any fever of 100.4 degrees F or above in a baby under 3 months (emergency regardless of suspected cause)
- Fever above 102 degrees F - this is NOT teething and needs evaluation
- Fever lasting more than 3 days (not caused by teething)
- Fever with other illness symptoms: rash, diarrhea, vomiting, cough, congestion (not teething)
Sources
Related Resources
Related Medical Concerns
Ear Infection vs. Teething - How to Tell the Difference
Ear pulling is one of the most commonly confused symptoms in babies - it can indicate either teething or an ear infection, and telling the difference can be tricky. Teething causes referred pain to the ear area (especially when molars are coming in), leading babies to pull or rub their ears. An ear infection typically follows a cold and is associated with fever, disrupted sleep, and increased fussiness. The key differences: teething ear pulling is usually without fever and is accompanied by drooling and gum swelling, while ear infections typically cause fever, follow a cold, and may cause more intense pain when lying down.
Baby Has a High Fever Over 104 Degrees F
A fever above 104 degrees F (40 degrees C) in a baby or toddler can be alarming, but the height of the fever alone does not necessarily indicate a more serious illness. Many common childhood viral infections (like roseola) can cause high fevers. What matters more than the number is how your child looks and behaves. A child with a 104 degree F fever who is still alert, making eye contact, and drinking fluids is less concerning than a child with a 102 degree F fever who is limp and unresponsive. However, fevers above 104 degrees F should always be discussed with your pediatrician.
Fever in a Baby Under 3 Months Old
A fever in a baby under 3 months old (temperature of 100.4 degrees F / 38 degrees C or higher taken rectally) is always a medical emergency. Go to the emergency room immediately, regardless of how well your baby appears. Young babies' immune systems cannot fight infections as effectively as older children, and a fever could indicate a serious bacterial infection (urinary tract infection, bacteremia, or meningitis) that needs urgent treatment. Do NOT wait to see if the fever goes down. Do NOT give fever medication and stay home - go to the ER first.
My Baby's Head Shape Looks Abnormal
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I'm Worried About Lazy Eye (Amblyopia)
Amblyopia (lazy eye) is the most common cause of vision loss in children, affecting about 2-3% of kids. It occurs when one eye develops weaker vision because the brain favors the other eye. The tricky part is that amblyopia often has no obvious outward signs - the eye usually looks normal. Early detection through routine vision screening is critical because treatment is most effective in the first few years of life.
Anaphylaxis Signs in Baby
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