Monitor for a slight temperature rise, not true fever

Teething may cause a very slight increase in body temperature, but it does not cause true fever. The AAP defines fever in infants as a rectal temperature of 100.4F (38C) or higher. Any temperature at or above that threshold should be evaluated by your pediatrician as a potential sign of illness, not dismissed as teething.

What Is Normal During Teething

• A mild temperature rise of up to about 99-100F (37.2-37.8C) in the day or two surrounding tooth eruption
• The slight warmth is thought to result from localized gum inflammation, not a systemic response

When to Call the Pediatrician

• Rectal temperature of 100.4F (38C) or higher
• Any fever in a baby under 3 months old (seek care immediately)
• Fever lasting more than 24 hours
• Fever accompanied by lethargy, poor feeding, rash, vomiting, or diarrhea

Tips

• Use a rectal thermometer for the most accurate reading in infants -- the AAP recommends this method for children under 3 years
• Do not assume that fever, diarrhea, or rash are teething symptoms -- research shows these are often coincidental illnesses during the teething age window
• Keep a log of temperature readings to share with your pediatrician if needed