All about fevers
Any spike in your baby’s temperature frightens parents. We clear the grey areas up for you.

It’s never easy dealing with a fever in your baby – the higher the thermometer reading climbs, the more worried we get, and with good reason. We hear so many things about fevers, a lot of them conflicting, that it’s hard to keep your wits (and the facts) about you when your little one’s temperature spikes.

That’s why we asked a paediatric ICU sister, Sr Catherine Rodwell, to clear up some of the confusion and give us only the facts about fever and our babies.


Warm clothing does not cause a fever

You cannot heat the body up to high temperatures such as 39°C by external warming, such as many layers of clothing or a very hot day. The body will start to sweat and will cool the person down. So if your child has a temperature over 38°C, it’s because he is experiencing an inflammatory response, telling you that something is wrong.

It is obviously very dangerous to leave a child in a car with the windows closed. The child will not be able sweat enough to cool down. He will experience extreme temperatures that his body cannot cope with. Children can quickly die like this.  

A febrile convulsion can happen at any high temperature

A temperature is considered “low grade” from 37.5°C. We’re often told that febrile convulsions happen at high temperatures, but babies and children can have a febrile convulsion from a temperature as low as 37.8°C. This is not the norm, but it can happen.

A rectal temperature reading is the most accurate

The most accurate way to take a temperature is with a mercury thermometer in the baby’s rectum as this is considered the core temperature in medical terms. Most parents are reluctant to check a temperature like this, so it is advisable that you add 0.5 of a degree onto the temperature you see on your digital thermometer (ear or underarm) for a more accurate reading.

A baby can have a high temperature from teething

Some children teethe worse than others. I have seen children who develop diarrhoea and the most painful bum rash from teething as well as a high temperature, but then there are babies that hardly notice they are teething at all!

It makes sense that babies can have a high temperature during teething, especially if those horrible molars and incisors are cutting through the gum. That could well set off an inflammatory response in your baby’s body, which could cause a spike in temperature. But take your baby to the doctor to rule out any other causes of fever.  

Sponging your baby down is a good idea

Tepid sponging is very effective when dealing with a fever, especially when you have a baby with a temperature of 40°C and you are waiting for medication to start working. Always use this as your first method of cooling the fever down.

Don’t put your baby into a bath; if he does start to convulse you won’t be able to control it and he may slip under the water. Rather take a bath towel and soak it in lukewarm water (cold water will cause shivering, which will only make the temperature spike further). Place your baby on a bed (securely), take all his clothes off and wrap him in the wet towel while you hold him. Be sure to cover his head too.

Giving a small baby cooled, boiled water (water that has been boiled and kept in the fridge) and a bigger baby some cold juice or an ice lolly is also effective for cooling. Fans are not a good method of cooling as they also cause shivering.

It is safer to use paracetamol with a fever

Anti-inflammatories are known to cause gastric ulcers and affect the kidneys when “over-used” on babies and small children. However, your baby’s paracetamol levels can become toxic at high doses, which is very dangerous, so don’t ever exceed your doctor’s prescribed dose, which he will calculate according to your baby’s weight.

If your baby needs more regular doses of medication to regulate her fever, your doctor may suggest alternating doses of paracetamol with anti-inflammatories to protect your baby from overdose.
It is important to monitor baby’s weight and how much has been given over what time period to prevent a toxic build-up of any of the drugs.

A fever fights infection

Your baby’s fever is merely an indication of infection, not a cure for it, so get your baby as comfortable as possible. By reducing a temperature with medication and tepid sponging, you are not preventing your baby’s body from fighting infection. You are not removing the body’s inflammatory response – that keeps on working.

What you are doing is alleviating the discomfort and pain of a fever and removing the dangers of a high temperature.


False: The body’s temperature wavers naturally between 36 and 38°C

In fact, anything over 37.5°C is not the body’s normal physiological temperature.The body’s natural response will be to sweat in higher tempartures, cooling the body down to remain under this cutoff.

False: You must only use medication for higher temperatures

Most paediatricians, GPs and nursing sisters start treating a temperature with paracetamol or an anti-inflammatory from 38°C. Having said this, some children may only present the symptoms of a fever with a temperature at 38.5°C or higher. This is why healthcare professionals always work with the patient’s presentation (what your baby looks like and is doing when the doctor examines him).

A baby or child who is eating, drinking and is alert is not a child they would panic about, even if his temperature is 38°C. The baby who is lethargic and not eating or drinking is more worrying, even if his temperature is actually lower. Remember that a parent’s instinct is most often right, so when in doubt, go to your doctor or to the emergency room.  

False: A fever is beneficial  over a period of time

Most medical professionals DO NOT believe that it is beneficial to expose your baby to high temperatures for long periods of time. We do not believe that by allowing your baby to endure fever we are "burning off the infection". In fact, it is dangerous to be exposed to high body temperature for extended times, as it can damage the body and brain if not treated.

Besides the possible damage to the brain, during a febrile convulsion your baby loses consciousness, which means his airway could be closed by the tongue and he could stop breathing. The patient might also start vomiting while they are convulsing, which can lead to choking.

False: Sweating during a fever cools your baby down

Note your body’s reaction the next time you have a temperature. You do not sweat, but you actually feel hot and dry. That’s because your body’s thermoregulation centre is not functioning correctly due to the inflammatory response.

Your baby’s body works the same way. After you give him paracetamol or an anti-inflammatory, and as it starts to work, you will see that he begins to sweat. At the same time, due to the analgesic effect of the medication, he will start to feel some relief from the pain and other symptoms. This sweating also helps cool the body down.

First aid courses

Learn about how to handle a febrile convuslion or other first aid emergency at Sister Catherine’s CPR courses. A CPR course is a must for any parent or childminder. Visit for more information.

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