High temperature (fever) in children

A high temperature in young children is common, and in most cases it is an ordinary viral infection that clears in a few days. What frightens parents is the figure on the thermometer; what concerns doctors is something else entirely, and that is the central idea of this page: what you go by is the state of the child, not the number. This page is about children; a high temperature in adults is covered on a separate page, "High temperature (fever) in adults", because the warning signs and the course of action there are its own.

You watch the child, not the thermometer

A child at 39.5C who drinks, answers you, plays between bouts of listlessness and knows their own people is less worrying than a child at 38.0C who is hard to rouse, does not reach out for you and lies there taking no interest. How high the temperature is says almost nothing about how serious the illness is: it depends on age, on what the child has caught and on the child's own way of reacting.

What matters is other things, and they are not hard to remember:

• how the child is breathing — calmly, or fast and with effort, with the skin drawing in between the ribs;
• how they respond — whether they recognise you, follow you with their eyes, answer to a voice and take an interest, or respond to nothing;
• whether they are drinking, and how many wet nappies there are in a day;
• the colour of the skin and lips — normal, pale, grey, blotchy, bluish;
• how fast things are changing — running about an hour ago, flat out now.

From this follows what to expect of medicines that bring the temperature down. They are given so the child feels better, so they will drink, eat and sleep, not to produce a tidy reading on the thermometer. A temperature by itself does not damage the brain and does no harm: it is the body's answer to an infection, not a fault. And the reverse holds too: if the medicine has brought the temperature down but the child is still flat and not themselves, that is no reason to relax. Perking up as the temperature falls is a reassuring sign, but it is not proof that the illness is a mild one.

Call an ambulance immediately if your child

• has a rash that does not fade when you press on it. Press the base of a clear glass against the spots: if they are still visible through the glass and do not disappear, this can be meningococcal infection, which moves within hours. The rash starts as a few small red or purple pinprick spots and is easy to miss in the hair, on the soles of the feet and on brown skin, so look everywhere and in good light. Do not wait for a rash to appear: in meningococcal infection it comes late, and sometimes it never comes at all;
• is hard to wake, is not responding the way they usually do, or is lying there taking nothing in;
• is grunting or moaning with every breath out;
• has had a seizure: the body stiffened, started jerking, and the child does not respond;
• is struggling to breathe — the skin pulls in between the ribs, under the ribs and in the hollow above the breastbone, the nostrils flare, the breathing is very fast or, on the contrary, has pauses in it;
• has gone pale, grey or blotchy, with blue lips or tongue;
• is a baby whose fontanelle is bulging and tense while they are calm and held upright;
• has a neck that will not bend, cannot bring the chin to the chest, is hurt by light, and has a severe headache;
• is crying non-stop with a high-pitched cry and cannot be comforted;
• has icy hands and feet while the body is burning;
• is a baby in the first months of life with a temperature — see the separate section below.

112 is the single European emergency number and works in Spain, Italy, Portugal, Poland and Ukraine; elsewhere dial your local emergency number.

A temperature in a baby's first months is a different conversation

The younger the child, the less you can rely on how they look. In a newborn and in a baby in the first months of life a temperature is always a reason to have them seen urgently, within the hour, however settled they seem. The reason is that an immature immune system cannot keep an infection in one place: a serious bacterial infection in such a baby can run without a single striking symptom and with a perfectly peaceful appearance, and the deterioration arrives all at once.

In the very young it is the quiet signs that matter rather than the loud ones: feeding weakly or refusing the breast and the bottle, sleeping unusually much and being hard to rouse, going floppy and hanging in your arms, grunting, breathing fast or with pauses, marbled skin. A low temperature should worry you too: in babies a serious infection often comes not with heat but with cooling, and that is no less dangerous.

The practical conclusion is a simple one: you do not wait until morning and you do not try seeing how it goes. A baby in the first months is not given anything to bring the temperature down without a doctor saying so, not because it will necessarily do harm, but because it hides the one visible sign by which this illness can still be caught.

A doctor the same day if

This is not ambulance territory, but it is not something to leave until next week either:

• the temperature has lasted more than five days;
• the child refuses to drink, is wetting noticeably fewer nappies, cries without tears, has dry lips and sunken eyes and is unusually listless — that is dehydration;
• any new rash has appeared alongside the temperature;
• there is a specific complaint next to the temperature: earache, stinging or pain on passing urine and smelly urine, a severe sore throat, a cough that is getting worse, tummy pain, a limp or refusing to put weight on a leg;
• the child is getting worse rather than better, or the temperature has come back after they had already recovered;
• the child has recently come back from the tropics: any fever after such a trip needs testing immediately, because malaria starts like an ordinary cold and runs more severely in children;
• the child has a long-term condition, is on treatment that suppresses immunity, or has had their spleen removed — in these cases you seek advice straight away rather than waiting for the fifth day;
• you simply feel that something is not right with your child. A parent notices the change before any scale does, and that is a legitimate reason to ask.

Febrile seizures

In roughly one child in twenty, between six months and five years old, a rapidly rising temperature brings on a fit: the child loses consciousness, the body stiffens, the arms and legs jerk rhythmically, the eyes roll up and the lips go blue. It usually lasts less than five minutes, after which the child comes round, often drowsy and washed out for an hour or two. For parents it is one of the most terrifying sights of their lives, which is why it helps to know in advance: seizures of this kind do not in themselves damage the brain, do not affect development and in the overwhelming majority of cases do not turn into epilepsy. They are an immature nervous system reacting to a jump in temperature, not a sign that the illness is a particularly bad one.

What to do during a fit: lay the child on their side on a flat surface, move away anything they could hit, put something soft under the head and note the time. Do not hold them down, do not force the mouth open and do not put anything in it — the tongue cannot be swallowed and does not fall back, whereas breaking a tooth or hurting the jaw that way is easy. Do not give anything to drink and do not push medicine into the mouth until they are fully round.

Call an ambulance if it is the first fit, if it lasts longer than five minutes, if fits follow one after another, if the child does not regain consciousness afterwards, is breathing badly or has blue lips. If your child is already known to have febrile seizures and the fit was short and typical, still contact a doctor the same day. Medicines that bring the temperature down do not, unfortunately, prevent these fits, so giving them just in case to avoid a seizure serves no purpose.

How to make the child more comfortable

If there is nothing worrying, the child stays at home, and what they need is simple.

• Offer drinks often and in small amounts — water, weak squash, diluted juice; put a breastfed baby to the breast more often than usual. If there is vomiting and diarrhoea, an oral rehydration solution from the pharmacy is the right thing.
• Dress them lightly, cover them with a sheet rather than a duvet, and air the room. If they are shivery and want a blanket, give them one, but take the extra layers off once the shivering passes.
• Feed them as much as they want and do not press food on them.
• Let them rest. Check on them regularly, including during the night.
• If the child is miserable, not sleeping and not drinking, give paracetamol or ibuprofen — one or the other. The dose comes from the leaflet for the children's preparation and is worked out by weight and age; if in doubt, ask a pharmacist or a doctor. Note that the adult preparations and adult doses described on the neighbouring page, "High temperature (fever) in adults", are of no use to a child in any form, and that different children's syrups come in different strengths, so the syringe or spoon from one bottle does not fit another.
• Keep the child at home while the temperature lasts.

What not to do

Do not sponge the child with cold water, do not wrap them in a wet sheet, do not rub them with alcohol or vinegar and do not undress them in a draught or in front of a fan: cooling the skin abruptly starts shivering, and with it the body temperature climbs higher still, while the child feels frankly awful. Alcohol and vinegar are also absorbed through the skin. Do not pile on layers either. Do not alternate paracetamol and ibuprofen by the clock as a routine, since it is a convenient way to lose track of doses; that is done only when a doctor says to. Do not give ibuprofen to a dehydrated child, a child with chickenpox, or one who is barely drinking. Aspirin is not given to children or adolescents at all. And do not wake a sleeping child to give medicine or take a temperature: the sleep is doing more good.

Why children get a high temperature

The overwhelming majority of cases are ordinary viral infections: colds, flu, stomach bugs, the viral rashes of childhood. In the first years of life a child meets them one after another, and eight to ten episodes a year in a little one at nursery is the normal run of things rather than a sign of weak immunity.

Among bacterial causes the commonest are middle ear infection, tonsillitis and pneumonia. Urine infection stands apart: in small children it often shows itself as nothing but a temperature, with no complaints about passing water at all, which is why it gets missed. If a temperature persists and there is no visible source, a urine test is one of the first sensible investigations.

A few more sources that come up most often:

• Vaccinations. A slight temperature in the first day or two after a vaccination is a usual and expected reaction and settles by itself. The schedule itself differs from country to country: follow your national programme and your own doctor.
• Teething. It can bring fretfulness, dribbling and a slight rise in temperature, but a high temperature is not explained by teeth. Blaming a reading of 39C on teething is a common and dangerous mistake: what you look for is an infection.
• Overheating. In a hot room, a stuffy car or under too many layers, a baby's body temperature rises with no illness at all. A child must never be left in a closed car, not even for a few minutes.
• A temperature lasting more than five days needs looking at in its own right. That is how Kawasaki disease shows itself, among other things: a rare inflammation of the blood vessels in children in which a prolonged fever is joined by red eyes without discharge, cracked lips and a strawberry tongue, a rash, swelling of the hands and feet and an enlarged gland in the neck. Recognising it in time matters, because the treatment protects the heart.

Online consultation

A child's temperature is the commonest reason for night-time panic and probably the most rewarding reason to talk to a doctor at a distance. In an online consultation the paediatrician will ask how the child behaves between the peaks, how they are drinking and weeing, how they are breathing and what came before the illness, will go through the rash with you and look at the child on video, and will help you work out whether an examination and tests are needed today or whether this can be watched calmly at home. They will suggest which form of medicine to choose and how to work out the dose for your child, explain what to expect over the coming days, and name the signs at which watching has to stop and an ambulance has to be called. If you can already see a rash that does not fade under a glass, a seizure, laboured breathing, a child who is hard to wake, or a temperature in a baby in the first months of life, an online appointment is not what is needed — an ambulance is.

This material is for information only and does not replace medical advice.