When to see a doctor with a child's fever

The height of the fever alone rarely decides. Age, duration and accompanying symptoms do. This list helps at 3 a.m.

Written by OUMM

Last updated: 9 October 2026

Call emergency services now

• a seizure, especially the first or one lasting over 5 minutes,
• difficulty breathing, grunting, chest sucking in, blue lips,
• a rash that does not fade when pressed with a glass,
• a stiff neck, bothered by light, a bulging fontanelle in a baby,
• cannot be woken (or keeps falling asleep), floppy, unresponsive,
• pale, grey, blue or blotchy skin; unusually cold hands and feet,
• a weak, high-pitched or continuous cry, unlike their usual cry.

Under 3 months: urgent

Any fever ≥ 38 °C is urgent. Contact a doctor or go to the emergency department straight away, including at night; do not wait until morning, even if the baby looks well. Do not give fever medicine without a doctor's advice. More on fever in the first months: fever in babies.

3-6 months: see a doctor the same day

• fever ≥ 39 °C,
• fever lasting over 24 hours,
• much less active than usual, not feeding.

Any child: see a doctor within a day

• fever ≥ 39 °C (a cautious rule of this site: NICE gives 39 °C as a threshold only for babies aged 3-6 months),
• fever over 3 days, or returning after a fever-free day,
• signs of dehydration: dry mouth, sunken eyes, crying without tears, a sunken fontanelle, passing little urine,
• ear pain, pain when passing urine, severe tummy pain,
• a rash that appeared with the fever,
• the child is listless, "not themselves", cannot be comforted (a more important sign than the number).

Whether the fever drops after a medicine does not tell you how serious the illness is (NICE); judge how your child is.

Check the temperature and age

Log the times of readings, doses and symptoms: the doctor will start with "since when and how high". A list from the last days shortens the visit and reduces the chance that something is missed.

Tired of keeping track on a scrap of paper?
Oh Fever records what you gave and when. Free for one child.

iPhone and Apple Watch

Shows the time since the last dose, the doses recorded in 24 hours and the leaflet tables and sentences word for word, with a link to the official leaflet. It does not calculate or suggest doses.

Download on the App Store

Android

Also shows the row of the leaflet table for your child's weight and age, counts down to the next dose the leaflet allows and warns before the daily limit is crossed.

Get it on Google Play

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