Q: My child was diagnosed with Influenza B and suddenly developed a 39°C fever. Should we get IV treatment?

Medically reviewed by Sang Hyun Ahn, MD

Content edited by Myeongchan Kim, MD

This post is a dramatization of a question and answer session experienced by our actual medical reviewers. Please note that this content is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.

Question:

My child was diagnosed with Influenza B yesterday. At the time, their cold symptoms weren't severe, and they didn't even have a fever, so the diagnosis was quite a surprise. We were prescribed oral medication and went home. However, starting early this morning, their cough has gotten much worse, and they suddenly developed a high fever of 39°C (102.2°F). In this case, would it be better to go back to the hospital today to receive IV treatment?

Answer:

It is completely understandable that you are worried about the sudden high fever and worsening cough after yesterday's flu diagnosis.

Things to check right now

If your child shows any of the following warning signs, please visit an urgent care center or emergency room immediately today:

• Difficulty breathing (e.g., skin pulling in under the ribs, flaring nostrils, wheezing)

• No urination for more than 8 hours

• Inability to drink fluids or keep food down, or continuous vomiting

• Difficulty waking up, poor eye contact, or decreased responsiveness

• Blue or pale lips and fingernails

What to do at home

• Fever reducers: Administer an appropriate dose of fever-reducing medication based on your child's exact weight and the concentration of the medicine.

• Hydration: Offer fluids (water, electrolyte drinks, or warm broth) frequently in small amounts every 5–10 minutes.

• Environment: Dress the child in light clothing and keep the room temperature comfortably cool. Avoid using wet towels or giving lukewarm sponge baths to reduce the fever.

Regarding Flu Antivirals

• It is important to start oral antiviral medications (like Tamiflu) within 48 hours of symptom onset. If your child has already started taking the prescribed oral medication, continue taking it for the full prescribed duration and dosage.

• Intravenous (IV) antiviral treatment is typically considered only when a patient cannot tolerate oral medications (e.g., severe vomiting) or has severe, life-threatening symptoms. If oral treatment has already begun, IV medication is generally not administered concurrently.

• If there are no severe warning signs as mentioned above, and the fever can be managed with oral fever reducers and proper hydration, you can continue with the current prescription and monitor your child's condition.

When to see a doctor again

• If any of the warning signs appear, visit an urgent care or ER immediately.

• If the fever lasts for more than 3 days despite taking fever reducers, or if the cough progressively worsens, your child should be re-evaluated by a doctor to rule out secondary complications such as pneumonia.

• We recommend contacting the clinic you visited yesterday to update them on the symptoms and get further advice. If it is after hours or the weekend, please utilize a local urgent care clinic or emergency room for an in-person evaluation.

For extra peace of mind and clear guidance when tracking your child's symptoms, the FeverCoach app is always there to help.

fevercoach.us

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