How to Manage Fever in Babies Under 2

Quick definition: For babies, a true fever is usually a rectal/ear/forehead reading of more than or equal to 38.0 °C, or an armpit reading of more than or equal to 37.3 °C. Use a digital thermometer; ear thermometers are best from about 6 months onward. When in doubt, confirm with a rectal reading.

Step 1 — Take the temperature correctly

• Under 4 weeks: use an armpit thermometer for screening. If febrile, confirm with a rectal reading if trained, or see a doctor.
• 4 weeks to <6 months: armpit or rectal. Ear thermometers are less reliable before 6 months.
• fever more than or equal to 6 months: ear (tympanic), forehead (temporal) or rectal. If readings seem off, confirm with rectal.

Step 2 — Keep baby comfortable at home

• Fluids: offer frequent breastfeeds/formula; a little water only if already on solids (ask your PD).
• Cool environment & light clothing: keep room well-ventilated; avoid over-wrapping.
• Rest: naps are fine; you do not need to wake baby just to check the number if otherwise well.
• Sponging? Not routinely needed. If you choose to sponge, use lukewarm water briefly and stop if baby shivers. Never use cold water or ice.
• Never use rubbing alcohol on skin to reduce fever.

Step 3 — Medicines (when baby seems uncomfortable)

Fever medicines don’t treat the cause; they help comfort. Dose by weight, not age. Check product strength before dosing.

Important: Avoid aspirin in children because of the risk of Reye syndrome. Do not routinely alternate paracetamol and ibuprofen unless your doctor specifically advises a schedule; it adds complexity and dosing errors.

When to see a doctor (non-emergency)

Febrile seizures (what to know)

• They can happen with rapid temperature rises in 6–60-month-olds. They are usually brief and not harmful.
• If a seizure occurs: lay baby on their side on a soft surface, don’t put anything in the mouth, and seek medical care. Antipyretics make babies more comfortable but don’t prevent febrile seizures.

Common myths

• “All fevers must be treated.” Not always. Treat discomfort, not the number.
• “Teething causes high fever.” Teething may raise temperature slightly but does not cause true fever (more than or equal to 38.0 °C). Look for another cause.
• “Sponging with cold water/alcohol helps.” Cold water can cause shivering; alcohol is dangerous. Stick to comfort measures and medicines as needed.

FAQ

Should I wake my baby to give fever medicine?

Generally, no. Prioritise rest and hydration. Give medicine if baby wakes and is uncomfortable, or as advised by your doctor.

Which thermometer should I buy?

A reliable digital stick thermometer works for armpit/rectal readings; add a tympanic (ear) or temporal (forehead) device once your baby is ≥ 6 months.

Could it be dengue?

If there’s high fever with severe aches, poor appetite, or you’re worried about mosquito exposure, see a doctor. Use paracetamol; avoid ibuprofen until dengue is ruled out.

This article is general information and does not replace medical advice. If you’re worried, see your GP/PD or go to a Children’s Emergency.