Fever itself is not dangerous
Fever is not harmful to the child in itself.2 It mainly shows that the body is reacting, often to an infection.
The context and other symptoms guide the assessment.
Health education · PediatricsPregnancy and pediatrics
Fever in children: understand, soothe and know when to seek care
Fever is common in children. To know what to do, consider the child’s age, general condition, hydration and other symptoms.
A child has a fever if their rectal temperature is 38.0 °C or higher.1,3
A baby under 3 months with a fever must be seen quickly by a doctor or at the emergency room.1
Fever
Why does a child get a fever?
Fever usually comes with an infection, viral or bacterial. It often goes away in about 3 days.2 It can also occur after some vaccines.3
Does a high fever mean a serious illness?
Not necessarily. How high the fever is does not show how serious the illness is: the child’s behaviour is a better guide.2
The temperature alone cannot determine whether an antibiotic is needed.
Temperature
How do you take a temperature?
Use a digital thermometer. Mercury thermometers should no longer be used.2
| Method | Fever if the temperature is… | Note |
|---|---|---|
| Rectal (bottom) | 38.0 °C or higher1,3 | The only reliable method at 2 years and under.1 Recommended before age 5.3 |
| Oral (mouth) | 37.5 °C or higher3 | Recommended after age 5.3,2 |
| Armpit | 37.5 °C or higher3 | In young children, a reading above 37.5 °C should be confirmed rectally.1 |
| Ear, forehead or no-contact | — | Quick but less accurate. A hat, sweat or the environment can affect no-contact readings.1,2 |
Good habits:
In a baby under 3 months, a rectal temperature of 36.0 °C or lower also calls for care without waiting.3
By age
What to do by age?
| Age | General approach |
|---|---|
| Under 3 months | See a doctor quickly or go to the emergency room. Do not give fever medication without medical advice.1 |
| 3 to 5 months | Call Info-Santé at 811 or see a doctor.1 |
| 6 months and older | If the child drinks well and seems healthy, home care is possible.1 Stay alert for warning signs. |
These guideposts do not replace specific instructions given for a child with a chronic illness or weakened immunity.
At home
What should you watch for at home?
The child’s behaviour tells you more than the number on the thermometer.2
Behaviour
Does your child respond to you? Can they be comforted? Do they wake up normally? Unusual drowsiness or inconsolable crying are warning signs.1,3
Breathing
Is your child breathing comfortably? Fast or difficult breathing, flaring nostrils, a high-pitched sound when breathing in or a sucking-in belly need prompt help.1,3
Hydration
Is your child drinking? Keeping fluids down? A very dry mouth, or little or no urine despite drinking enough, can signal dehydration.3
Comfort
How can you make your child more comfortable?
A few simple steps help a child get through the episode:
- offer drinks often, unless a professional advises otherwise;1,3
- let your child rest;3
- offer food according to appetite;
- remove extra blankets and clothing, without undressing your child completely: shivering can raise the temperature.2,1
Cold or lukewarm baths, ice and rubbing alcohol are not recommended: they make the child uncomfortable and their effect is short-lived.1,3
Medications
Should you always give medication?
No. Medication is mainly for comfort. A child with a fever who does not seem sick does not necessarily need it.1
Acetaminophen or ibuprofen lower fever temporarily, without treating its cause.2 The temperature can therefore rise again as the effect wears off; this is not a reason to give doses closer together.
Precautions
- Under 3 months, do not give acetaminophen without medical advice.1
- Ibuprofen is not suitable under 6 months, for a child who is dehydrated or not drinking, or with chickenpox, unless a doctor advises it.1,2,3
- Never give aspirin (acetylsalicylic acid) to a child for fever, because of the risk of Reye’s syndrome.1,2
Important points:
- the dose is based on the child’s weight, the product and its concentration; if in doubt, ask your pharmacist;1,3
- respect the interval between doses and the maximum number of doses per 24 hours;1
- use the dropper or syringe provided, or a graduated oral syringe from the pharmacy, not a kitchen spoon or a cup;1
- write down the medication, the dose and the time;
- do not give both medications at the same time without a professional’s recommendation.1 If you alternate them, respect each one’s interval.3
Seeking care
When should you book a consultation?
Don’t wait for these timelines if you are worried about your child. Info-Santé at 811, option 1, offers nursing advice any time.3
The Canadian Paediatric Society recommends seeing a professional if the fever lasts more than 48 to 72 hours.2 For a young child or one with a particular condition, earlier advice may be needed.
See a professional in particular if:
When should you go to the emergency room?
Go to the hospital without waiting if the child:1,3
- is under 3 months and has a fever;1
- is hard to wake, drowsier than usual or not very responsive;1,3
- is confused, agitated or behaving unusually;3
- cries constantly and cannot be comforted;1,3
- has difficult or fast breathing, or bluish lips or fingers;1,3
- is pale or an abnormal colour;1
- has a stiff neck or neck pain;3
- has a seizure;1,3
- has a very dry mouth or little or no urine despite drinking enough;3
- vomits a lot, or has a fever with back or side pain;1,3
- after a vaccine, has a rectal temperature above 38 °C for more than 4 hours, or above 40 °C.3
Fever with red or purple spots that do not fade when you press on them is a medical emergency.5
Call 911 if the situation is serious and urgent.1
Seizures
What about febrile seizures?
A seizure can happen during a fever. It affects 2 to 5 % of children aged 6 months to 5 years.1
Call 911 if the child is under 6 months, if the seizure lasts more than 3 minutes, if their condition worsens or if they do not recover well.1
After a seizure, even a short one, see a doctor within the next few hours or go to the emergency room.1
During the seizure:1
- lay the child on their side, on a flat, safe surface;
- move dangerous objects away;
- do not try to stop the movements;
- do not put anything in the child’s mouth;
- note the time it started.
Antibiotics
Does a fever need antibiotics?
Not always. Antibiotics do not work against infections caused by viruses, such as colds and flu.4
The decision depends on the suspected or confirmed cause of the fever. How high the fever is does not, on its own, show how serious the illness is.2
The visit
What should you note before a visit?
This information makes the assessment easier.
Have ready:
- age and recent weight;
- the date the fever started;
- temperatures and the method used;
- medications, doses and times;
- how much the child drank and how often they urinated;
- other symptoms;
- recent vaccines, known conditions, usual treatments and recent travel.
When to consult at the Clinique IPS du Palais?
Depending on the symptoms and availability, various common health problems in children can be assessed at the clinic. A nurse practitioner can examine your child, look for the cause of the fever and advise you on care.
A baby under 3 months with a fever must be seen quickly by a doctor or at the emergency room. If the situation is serious and urgent, call 911.
Sources
- Institut national de santé publique du Québec (INSPQ). Fièvre, Mieux vivre avec notre enfant de la grossesse à deux ans (in French). Updated February 17, 2026, accessed October 29, 2026. inspq.qc.ca
- Canadian Paediatric Society, Community Paediatrics Committee. Fever and temperature taking, Caring for Kids. Updated June 2022, accessed October 29, 2026. soinsdenosenfants.cps.ca
- Santé Québec. Fièvre (0-11 ans) (health advice, in French). Updated September 8, 2026, accessed October 29, 2026. sante.quebec
- Health Canada. What you need to know about antimicrobial drugs, including antibiotics (fact sheet). Modified December 17, 2024, accessed October 29, 2026. canada.ca
- The Royal Children’s Hospital Melbourne (Australia). Rashes, Kids Health Info. Reviewed November 2025, accessed October 29, 2026. rch.org.au
This sheet provides general information and does not replace an assessment by a health professional. Published October 29, 2026.