You’re not alone – many of us fear the dreaded fever when it comes to our tiny loves. It’s typically the first sign that something is going on with our baby and we rush around, grabbing all the medicine, preparing for the worst. Let’s start instead by congratulating our babe’s immune system for doing its job and see how this plays out.

Fevers are caused by:

  • Illnesses (viral or bacterial)
  • Vaccinations
  • Overheating

What is a normal baby temperature?

As a whole, our body temperature can range quite a bit throughout the day. It is lowest in the morning and highest in the late afternoon. A normal rectal temperature reading can range from 96.8 to 100.3, with an average of 98.6.

When is an infant fever too high?

If your baby is <3 months old and your Kinsa thermometer is reading a rectal temperature of 100.4 F or higher, call your pediatrician. He/she will get you in for an appointment or suggest you head to an urgent care facility or emergency room. It’s hard to assess a baby fever at this age and things can escalate quickly – better safe than sorry. And remember: we don’t medicate our little ones on our own; let your doctor be your guide!

For our babies who are 3 months to 6 months old, we can let their fever hit 102 F before we start to worry. And for 6 months to 2 years old, we can let their fever get to 104 F. You don’t even need to medicate any of these kiddos before the 102 F mark! If they are uncomfortable, you may give them Tylenol (or ibuprofen if they are >6 months old), but otherwise it’s okay to let that fever get rid of the virus for them. No aspirin. Keep your babe hydrated and make sure she’s not overdressed or wrapped in too many blankets.

It is a common misconception that we must rotate Tylenol and ibuprofen, but choosing just one is actually preferred. If the one you chose does not bring the fever down 2-3 degrees F within an hour, you may switch to the other medication. Our biggest concern is accidentally overdosing our kids – the less we give, the less we need to worry!

How to take a baby’s temperature?

  • Birth to 6 months old: A rectal temperature is the most accurate and the gold standard here. A temporal artery thermometer is also gaining popularity with this age but if you’re ever questioning the results, stick with rectal.
  • 6 months old to two years old: Temporal artery temperature, armpit (axillary) temperature, ear (tympanic) temperature, or rectal. Again, rectal is the most accurate when in doubt. Axillary is the least accurate.

When to call your pediatrician?

  • Fever >100.4 F for our babes <3 months old
  • Fever >102 F for our babes >3 months old to 6 months old
  • Fever >104 F for our babes >6 months old to 2 years old
  • Your baby is lethargic
  • You notice signs of dehydration (dry mouth, no tears, no wet diapers >8 hrs)
  • Burning or pain with urination
  • Fever is accompanied by other symptoms that concern you (pulling at ears, vomiting, diarrhea)

When to go to the ER with fever?

  • Difficulty breathing
  • Disoriented/confused
  • Seizures
  • Stiff neck

When is a fever dangerous?

A truly dangerous fever is >108 and is extremely rare, only seen in situations such as a heat wave. However, all fevers >105 should be investigated with a doctor as stated above. That said, less than 1% of fevers go higher than 105.

How to break a fever?

Rest, drink lots of fluids, and stay cool! Remember that fever is on our side, fighting off our infections. So unless our baby’s fever hits 102 as discussed, there is no ‘breaking’ necessary.

Are fevers contagious?

Not necessarily. If a virus is the reason your baby has a fever, then yes, they are considered contagious. But as discussed in the beginning here, vaccines or overdressing can also cause a fever – not contagious. And there are plenty of illnesses that may NOT cause a fever, so in general, don’t use fever as your guide on whether or not it can be spread to others.

Keep in mind that how your baby is behaving is always more important than the actual number on your Kinsa thermometer. Follow your gut if you feel like something is wrong, but otherwise don’t be afraid to let your love’s immune system be the champion!

Blake WagemanNurse Blake:

Blake Wageman, RN, BSN has over 11 years of nursing under her belt, primarily focused on NICU babies and, just as importantly, their worried parents. She also has two daughters who have kept her on her toes from birth all the way into their tween years. Blake’s passion is giving parents not only the information, but also the comfort and confidence they need to make good decisions for their kiddos.

This content is intended for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis or treatment from an appropriately qualified and licensed physician or other healthcare provider.

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