The age rule comes first
A temperature of 38°C or above in a baby under three months needs urgent medical advice. Do not wait until morning to see whether it settles.
For babies aged three to six months, 39°C or above is a reason to get urgent advice. At any age, how your baby looks and acts matters as much as the number.
How we check a temperature
A digital thermometer in the armpit is the usual home method for a young child. We report the number and where we took it rather than adding or subtracting anything.
Watch the baby between the spikes
Are they looking at you, drinking and reacting normally? Or are they floppy, unusually quiet, hard to wake or struggling to breathe? Those changes matter.
At home, small frequent drinks and one comfortable light layer can help. A cool cloth may feel soothing, as it did for Ari, but it does not treat the fever.
For pain or discomfort, use only medicine suitable for your child and follow advice from your baby’s doctor, nurse or pharmacist. We are leaving exact dosing out because age, weight and the product all matter.
Trust the part of you that knows your baby. If something looks wrong, ask for help quickly even if the thermometer has not reached a neat threshold.
Call your doctor if
- Under three months with 38°C or more
- Three to six months with 39°C or more
- A rash that does not fade under a glass
- Hard to wake, floppy or struggling to breathe
- A seizure, very few wet nappies or your instinct says something is wrong