Fever in Children: What Parents Need to Know
What is a Fever?
A fever is generally considered a body temperature of:
- 100.4°F or higher in an infant under 3 months (usually measured rectally) - this is an emergency and we ask that you contact us urgently
- 100.0°F or higher in a child over 3 months of age
Most commonly, a fever is the body’s natural response to an infection. While it can be alarming, it’s often a sign that the immune system is doing its job. For most children, a fever may be uncomfortable, but it usually isn't a cause for serious concern. For infants, however, even a low fever may mean there's a serious infection.
What matters most is how your child is feeling. Some children handle fevers well and remain playful, while others may seem tired, fussy, or uncomfortable. You can help manage a fever at home by keeping your child cool and hydrated. Offer fluids regularly and let them rest as needed. If they seem uncomfortable, fever-reducing medications like acetaminophen or ibuprofen can help—just be sure to use the correct dose for their age and weight.
While most fevers are not dangerous and will resolve on their own in a few days, there are times when you should call your pediatrician right away—especially if your baby is under 3 months old, if the fever lasts more than three days, or if your child seems unusually sleepy, irritable, has trouble breathing, or shows signs of dehydration. If you ever feel unsure, trust your instincts and reach out—we’re here to support you.
Fever Facts
- Fever itself is not harmful- it’s a symptom, not a disease.
- Treat based on how your child feels, not just the number on the thermometer. You don't necessarily need to treat a fever if it's not causing discomfort.
When to Call the Doctor
- Your baby is under 3 months and has a temperature 100.4°F or higher
- Your child seems very drowsy, irritable, or unresponsive
- There are signs of dehydration (dry mouth, no tears, fewer wet diapers)
- They have trouble breathing, a stiff neck, or a persistent non-fading rash
Please call us for an appointment during office hours if:
- Your child’s fever lasts more than 3 days, especially if your child has no other symptoms
Another helpful website for support and additional education on fevers:
https://www.healthychildren.org/English/health-issues/conditions/fever/pages/Fever-Without-Fear.aspx
| Weight (lbs) | Children or Infant Acetaminophen (160 mg/5 mL) | Children’s Ibuprofen (100 mg/5 mL) ***see below for infant dosing | Diphenhydramine (12.5 mg/5 mL) |
|---|---|---|---|
| 12–17 | 80 mg (2.5 mL) *if under 2 months, please call us | Not recommended under 6 months | 6.25 mg (2.5 mL) |
| 18–23 | 120 mg (3.75 mL) | 80 mg (4 mL) | 9.375 mg (3.75 mL) |
| 24–35 | 160 mg (5 mL) | 100 mg (5 mL) | 12.5 mg (5 mL) |
| 36–47 | 240 mg (7.5 mL) | 160 mg (8 mL) | 18.75 mg (7.5 mL) |
| 48–59 | 320 mg (10 mL) | 200 mg (10 mL) | 25 mg (10 mL) |
| 60–71 | 400 mg (12.5 mL) | 200 mg (10 mL) | 31.25 mg (12.5 mL) |
| 72–95 | 480 mg (15 mL) | 320 mg (16 mL) | 37.5 mg (15 mL) |
| 96–120 | 640 mg (20 mL) | 420 mg (21 mL) | 50 mg (20 mL) |
*** Infant ibuprofen is twice as concentrated so HALF all of these amounts if giving infant ibuprofen drops, ie, for an 18lb baby give 2ml of infant drops.
