How Long Does a Fever Last in a Child? What's Normal and When to Worry
Most fevers in children are caused by viral infections and settle within 3 to 5 days on their own. Flu fever often lasts 3 to 5 days. A fever lasting more than 3 days without a clear cause, or one that goes away and comes back with new symptoms, is the point to check in with your GP or polyclinic.
Under 3 months: any temperature of 38.0°C or above needs urgent assessment today, however long it has lasted. Fever in a baby under 3 months
Typical fever duration
Most fevers in children are caused by common viral infections and settle within 3 to 5 days on their own, with or without fever medicine. The medicine does not shorten the illness, it just makes your child more comfortable while their body deals with it.
A fever that comes and goes within a day, dipping after medicine and rising again before the next dose, is the medicine wearing off, not a sign the fever is getting worse or lasting longer than it actually is.
Duration by type of illness
Fever usually lasts 2 to 4 days, often settling before other symptoms like a runny nose or cough.
Can cause a high fever, often lasting 3 to 5 days, alongside body aches and tiredness, even without anything going wrong.
A high fever for 3 to 5 days that resolves around the time a rash appears on the trunk. The rash itself is not a cause for concern.
Fever often lasts a day or two, alongside mouth sores and a rash on the hands, feet, and sometimes nappy area.
Fever may continue until appropriate treatment is started, and can improve within a day or two of starting antibiotics if one is prescribed. See the doctor again if your child is not improving after 48 to 72 hours on antibiotics.
These are general patterns, not a way to diagnose what your child has. The same fever duration can come from very different illnesses, which is why how your child looks and behaves matters more than matching symptoms to a list.
→ Fever with rash in a child: what to check first
When to see a doctor
Call your GP or polyclinic if the fever has lasted more than 3 days without a clear cause, even if your child otherwise seems well. This is also the point where a blood test might be suggested to look for causes such as a bacterial infection or, in Singapore, dengue.
- The fever has lasted more than 3 days without a clear cause.
- Your child is more tired or quieter than usual, even between doses of medicine.
- A new symptom appears partway through, such as a rash, ear pain, or persistent vomiting.
- A fever lasting 5 days or more, especially with red eyes, red cracked lips, a rash, or swollen red hands or feet. This can be Kawasaki disease, which needs a same-day check.
→ Fever not coming down with paracetamol: what to do
When a fever goes away and comes back
There is a difference between a fever dipping with medicine and rising again before the next dose, which is expected, and a fever that goes away completely for a day or more and then returns. The second pattern is worth a call to your GP or polyclinic, especially if a new symptom has appeared in between.
In Singapore, this pattern is also worth keeping in mind for dengue, where warning signs can appear once the initial fever has started to settle, not while it is at its highest.
→ Toddler fever 39°C: when to monitor vs seek help
→ Dengue fever in children: symptoms and warning signs in Singapore
When to get help now
Call 995 now if your child has a fever and any of these:
- !A seizure lasting more than 5 minutes (give rectal diazepam if a doctor has prescribed it, and still call)
- !Struggling to breathe (skin pulling in under the ribs, nostrils flaring, or grunting), pauses in breathing, or lips turning blue or grey
- !Cannot be woken, or floppy and not responding to you
- !A rash of small red or purple spots that does not fade when you press a glass on it
- !Swelling of the lips, tongue, or face, with any difficulty breathing
- !Cold, clammy, or mottled skin, with drowsiness or restlessness
Go to the nearest 24-hour A&E or children's emergency now if:
- !A baby under 3 months with a temperature of 38.0°C or above
- !A first febrile seizure, even if it has stopped
- !After a seizure: confused, still drowsy after 30 minutes, or more than one seizure in a day
- !A stiff neck, or crying in pain when bending the head forward
- !Unusually drowsy or hard to wake, but can be woken
- !Dengue warning signs as the fever comes down: tummy pain, repeated vomiting, bleeding gums or nose, or very tired
- !No urine or wet nappy for 12 hours or more
- !No tears when crying, sunken eyes, or a very dry mouth
- !Cannot keep any fluids down
- !Green vomit
- !A temperature above 40°C that is not coming down, and your child seems unwell
Frequently asked questions
How many days of fever is considered normal in a child?+
Most fevers caused by common viral infections settle within 3 to 5 days. A fever on its own for a day or two, in a child who is otherwise drinking and not getting more unwell, is not unusual. The point to check in with your GP or polyclinic is when it passes 3 days without a clear cause.
My child's fever went away and then came back. Is that normal?+
It depends on the pattern. If the fever dips after medicine and creeps back up before the next dose is due, that is the medicine wearing off, not a new problem. If the fever was fully gone for a day or more and then returns, especially with a new symptom such as a rash, looser stools, or your child seeming more unwell than before, that is worth a call to your GP or polyclinic rather than assuming it is the same illness restarting.
Does a fever lasting longer mean the illness is more serious?+
Not necessarily. Some common viruses, including influenza, often cause fevers lasting 3 to 5 days without becoming serious. Duration alone is not the most useful signal. How your child looks and behaves between fever spikes, and whether new symptoms appear, generally tells you more than the number of days.
The fever is gone but my child still seems unwell. What now?+
A fever settling does not always mean the illness is over. Some children take a few more days to get back to their usual energy, appetite, and sleep. If your child seems persistently more tired, withdrawn, or off their food well after the fever has gone, or develops a new symptom, check in with your GP or polyclinic.
When should I worry about a fever lasting more than a week?+
Any fever lasting more than 3 days without a clear cause should be checked by a GP or polyclinic if it has not been already. A fever lasting 5 days or more, especially with red eyes, red cracked lips, a rash, or swollen red hands or feet, can be Kawasaki disease, which needs a same-day check. By this point a doctor will usually want to examine your child and may suggest a blood test to look for causes such as a bacterial infection or, in Singapore, dengue.
Does teething cause a fever that lasts for days?+
Teething can cause a very mild, short-lived rise in temperature in some children, but it does not cause a fever that lasts for days. Teething does not cause a temperature of 38°C or above. Treat it as an illness and look for another cause.