Little Kids

Everything you need to know about treating a fever in kids

Is your child feeling warm? We asked the experts the best way to check for a fever, how to treat it and when it's time to head to the doctor's.

Everything you need to know about treating a fever in kids

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You know the signs: Your little one is acting lethargic and when you feel her forehead it’s hot to the touch. Fever in kids is common, but the good news is they’re not dangerous. “People worry about fevers harming the child in some way, especially if they are high, but fevers just tell us something is going on,” says Joanna Holland, a paediatrician at IWK Health Centre in Halifax. “A fever is a sign that the body’s immune system has been activated and it’s fighting an infection, which is exactly what it’s supposed to do.” So when it comes to treating a fever in kids, it’s really a matter of making her comfortable.

Here’s what you should know to bring down a fever.

Detecting a fever in kids

The most reliable way to check whether your child has a fever is to use a standard digital thermometer. But as Natalie Orovec, an assistant clinical professor of paediatrics at McMaster University and a paediatrician in Stoney Creek, Ont., says, how you use it will depend on your child’s age and ability to hold still through the process.

The most accurate way to take a temperature is rectally, and that’s the method Orovec recommends for kids under the age of two, but this might not be the best option for your squirmy toddler. So, from ages two to five, the armpit method tends to be easier for parents. When measuring the underarm temperature, the end of the thermometer should be in the armpit itself, not sticking out the other side, with the arm folded down so the device can measure the temperature of the main artery in the armpit. Kids five and up should be able to have their temperature taken orally, with the thermometer under the tongue and the mouth closed. Orovec isn’t a fan of ear thermometers because it’s hard to seal them into the ear before they beep, which causes them not to work sometimes. And the Canadian Paediatric Society does not recommend temporal artery thermometers—which measure temperature at the forehead—for home use.

If the temperature comes in above 38°C (100.4°F), the child is running a fever, but there are slight differentiations in temperatures among each method. When measured rectally, a normal temperature should fall somewhere within 36.6°C and 38°C (97.9°F and 100.4°F), whereas normal range for the armpit should fall within 36.5°C and 37.5°C (97.8°F and 99.5°F) and a normal temperature for the mouth is 35.5°C to 37.5°C (95.9°F to 99.5°F).

Though a high number on the thermometer can set off alarm bells, Holland says a higher fever doesn’t necessarily mean more cause for concern. “You can have a very high fever with just a cold,” she says. “I’m constantly reassuring parents that the fever itself is not doing harm to the body,” says Orovec. “They ask, ‘If my child has a temperature of 104°F, is that going to cause any damage to them?’ And the answer to that is no. It’s actually a response to your body fighting off an infection.”

When to treat a fever in kids

The temperature on the thermometer alone shouldn’t determine how you treat it. “It’s not so much the number you should worry about; it’s what your kid looks like,” says Orovec. Is your kid running around and playing? Or is he lying on the couch and refusing food?


If your child is holding up OK, it might just be a matter of treating any fever-related discomfort through non-medical interventions, suggests Sean Simpson, chair of the Ontario Pharmacists Association and pharmacist at Simpson’s Pharmacy in Niagara-on-the-Lake, Ont. “You want to make sure they’re not too hot with clothes or blankets, and use a wet cloth to provide some relief. Another thing to consider is hydration, because kids with fevers can lose water,” he says. In many cases, water alone will do the trick, but he says oral rehydration solutions like Pedialyte can help when there is additional water loss from vomiting and diarrhea. Though a cool cloth pressed against the forehead and armpits can help bring temperature down, cold baths or showers should be avoided as they can make temperature drop too fast, and actually cause the fever to spike in response, says Orovec.

Determining the dose

When your kid is clearly feeling terrible, either ibuprofen or acetaminophen can help. Both drugs are antipyretics (fever reducers) and analgesics (pain relievers), but they are processed by the body differently. When it comes to fever in kids, both drugs work equally well, but Orovec says that, while acetaminophen tends to act a little faster, ibuprofen lasts longer. Simpson suggests it might come down to flavour preference—if one comes in bubble gum and your child only likes grape, the medicine he prefers will be most successful. Do not give your child acetylsalicyclic acid (Asprin) because it can cause Reye’s syndrome, an illness that can cause brain and liver damage.

If your child is experiencing vomiting or diarrhea, or is having trouble eating and drinking, you might want to avoid ibuprofen, though. “Ibuprofen is processed by the kidneys and can, in some circumstances, cause problems with the kidneys if the child is dehydrated,” explains Simpson.

When it comes to measuring out the appropriate dose, use the amount recommended on the medication’s packaging, and be sure to use the enclosed measuring cup or an oral syringe, which you can find at the pharmacy. “No spoon is the same, so we don’t dose with teaspoons and tablespoons anymore,” says Simpson. Doses are recommended based on weight ranges, so it’s important to know how much your child weighs.

Doctors administer ibuprofen at 10 milligrams per kilogram every six to eight hours and acetaminophen at 15 milligrams per kilogram every four to six hours. Over-the-counter drugs are similarly based on weight, though age may also be provided on the box as a guide; look for the dosing table on the packaging and use the dose recommended for your child’s weight range. If you have a young child who is heavy for his age, however, it’s safer to use the lower dose. It’s important to read the instructions carefully as the concentrations of each medication may be different.

Seeing results


Some parents will alternate doses of ibuprofen and acetaminophen in an attempt to lower a fever faster. But the goal should always be to treat for comfort, not to bring down a temperature back to normal. If your child isn’t responding to the first medication after a few hours, you can try the other type offever reducer as long as you stick to the dosing schedule for each medicine.

You need to be very careful when administering alternate doses to avoid any dosing errors. Acetaminophen can’t be administered more than every four hours because overdosing can cause damage to the liver and ibuprofen can’t be given more often than every six hours or it can cause problems with the kidneys if the child is dehydrated. Simpson recommends writing down the time and dose when you give your kid medication to avoid overdosing and to prevent confusion when you’re sharing caregiving duties with a partner or babysitter.

“The biggest danger is rushing things along,” says Simpson. “We all want our children to be comfortable, but overmedicating doesn’t provide a long-term benefit.”

Within the first couple of hours of giving your child medicine, the fever should start to come down, but don’t expect it to reach normal temperature before you stop dosing out meds. Instead, look to their behaviour for cues to stop medicating.

Remember: You treat for comfort, not for the number on the thermometer.


“If the child seems to be feeling better, the child doesn’t need the medication anymore,” says Holland. Orovec agrees, adding that if your kid is eating and drinking well, and becoming more active again, “I would hold off on the medication and keep an eye on them to see what transpires.” After the medication wears off, it’s possible the fever will return if your child’s body is still fighting an infection.

When to see a doctor

If the fever continues for more than 72 hours, it’s a good idea to have your child checked out by a doctor, says Holland, especially if there are no symptoms of a common virus, like a runny nose or cough. All doctors agree that any infant up to three months who has a fever should receive medical attention right away because there is the risk of a more serious infection. If your child is excessively fussy, irritable, sleepy or unresponsive, or they are wheezing, coughing or have a rash, it’s also a good idea to see a doctor.

This article was originally published on Dec 07, 2019

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