Q: My child received IV flu treatment. The high fever is gone, but a mild fever (37.5-37.6°C) persists. Do we need antibiotics?
- Myeongchan Kim, MD
- Jun 28
- 3 min read
Updated: Jul 8
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 the flu on the 3rd and received IV antiviral treatment. Fortunately, the high fever subsided. However, since yesterday, my child has had a continuous mild fever fluctuating between 37.5°C and 37.6°C. The medication we are currently taking already includes a fever reducer. Is it okay if this mild fever continues? Or should we visit the clinic to get an antibiotic prescription?
Answer:
It is completely understandable to be concerned about a lingering mild fever during flu treatment.
Understanding the Current Situation
After receiving the IV flu treatment, the high fever has been successfully controlled. However, a mild fever of 37.5°C to 37.6°C (99.5°F - 99.7°F) has been persisting for two days, even while taking medication that includes a fever reducer.
Why You Can Be Reassured
Normal Timeline: Even with antiviral treatment, flu symptoms can naturally persist for 3 to 5 days.
Signs of Recovery: If the mild fever does not spike into a high fever again, and your child is eating and playing reasonably well, it is highly likely that they are simply in the normal recovery phase.
Role of Antibiotics: Antibiotics are only necessary when there is evidence of a secondary bacterial infection (such as yellow mucus or phlegm lasting more than 10 days, suspected ear infection, or pneumonia). They do not treat viral infections like the flu.
What to Do at Home Right Now
Hydration: Offer plenty of fluids frequently (water, electrolyte drinks, or warm broth).
Environment: Dress your child in light clothing and maintain a comfortable indoor temperature around 20–22°C (68–72°F).
Medication: Give fever reducers only if your child is visibly uncomfortable or in pain. A mild fever itself is a natural immune response and does not strictly require fever-reducing medication if the child is comfortable.
Rest: Ensure they get plenty of rest and sleep to help their body fight off the virus.
When to See a Doctor
Please visit your pediatrician for an in-person evaluation if any of the following occur:
The fever rises above 38°C (100.4°F) again or the fever lasts for more than 5 days.
Your child has difficulty breathing, is breathing very rapidly, or complains of chest pain.
Thick yellow or green mucus/phlegm persists for more than 10 days, or they complain of ear pain.
There is a sudden drop in urine output (no urination for over 8 hours), severe lethargy, or a complete refusal to eat or drink.
Regarding Antibiotics
Antibiotics are not effective against the flu virus itself. They are only prescribed when a doctor diagnoses a bacterial complication (like an ear infection, sinus infection, or pneumonia) after a physical examination. At this stage, there is no need to proactively seek an antibiotic prescription.
Please continue to monitor your child using the guidelines above, provide supportive care at home, and consult your pediatrician if their symptoms worsen or if the fever spikes again.
For extra peace of mind and clear guidance when tracking your child's symptoms, the FeverCoach app is always there to help.
