Q: My child has a 5-day fever and exudative tonsillitis. The fever still fluctuates after two doses of antibiotics. Should we go back to the doctor?
Updated: Sep 7
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 has had a fever for 5 days. There is no cough at all, just a very stuffy nose and the fever. Over the weekend, tests for the flu, Adenovirus, COVID-19, and RSV all came back negative. The fever drops when we give fever reducers, but it spikes back up to 38.5°C (101.3°F) in the evening.
We went to the ER yesterday; the chest X-ray was clear and breathing sounded good. However, the doctor diagnosed exudative tonsillitis, noting that the throat was severely swollen with white patches. We were prescribed a 5-day course of antibiotics. We have only given two doses so far (last night and this morning), but the fever keeps fluctuating. I'm scared because my child has never had a fever last this long. Do we need to go back to the hospital right away?
Answer:
It must be very stressful and exhausting to deal with a high fever lasting for 5 days.
[Current Situation Summary]
Your child was diagnosed with exudative tonsillitis (bacterial pharyngitis) and started antibiotics, but has only taken 2 doses so far.
Respiratory virus tests are negative, the chest X-ray is normal, and there is no cough.
The fever responds well to fever reducers but rebounds to 38.5°C in the evening.
[When Will the Antibiotics Work?]
It typically takes 24 to 72 hours after starting antibiotics for a fever pattern to significantly break. Since your child has only taken two doses, it is still too early to judge the effectiveness of the medication.
[What to Do at Home Right Now]
Finish the antibiotics: Give the medication at the exact prescribed time intervals until the course is completely finished. Never stop antibiotics arbitrarily, even if the fever goes away.
Manage the fever: Use fever reducers only when the child is uncomfortable. There is no need to force the body temperature down to zero if they are resting peacefully.
Hydration: Offer small, frequent sips of water. This helps soothe the throat pain and prevents dehydration.
Comfort: Maintain indoor humidity between 40-60%, and use saline nasal drops or sprays to help with the stuffy nose.
[When to Seek Immediate Medical Re-evaluation]
If any of the following warning signs occur, please take your child to see a doctor for a re-evaluation today:
The fever (38°C / 100.4°F or higher) continues even after a full 3 days of taking antibiotics.
The throat pain becomes so severe that your child cannot swallow their own spit or is drooling.
Your child has difficulty breathing or their voice suddenly changes.
There is no urine output for more than 8 hours.
Your child becomes extremely lethargic, unresponsive, or cannot make eye contact.
[Next Steps]
If possible, it is best to follow up with your regular pediatrician rather than returning to the ER. You can call their office, explain the ER diagnosis, and ask them how many more days you should observe the fever pattern. While the ER is necessary for nights and weekends, visiting your regular clinic during daytime hours is usually more efficient.
To summarize: The effect of the antibiotics should be evaluated after 48 to 72 hours. For now, prioritize accurate dosing, hydration, and close observation. If the fever persists on the 3rd day of antibiotics or if you notice any of the warning signs listed above, please consult your doctor 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.
