Q: My child got a fever after taking antibiotics for bronchitis for one day. Does this mean the medicine isn't working?
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:
Hello, my child was diagnosed with bronchitis (with a cough and phlegm) and was prescribed antibiotics to take twice a day. I gave them two doses yesterday and one dose today. They were fine during the day, but when I checked their temperature before the evening dose, they had a fever. Does this mean the antibiotic isn't working? Should we go back to the doctor immediately, or is it okay to observe them for another day?
Answer:
Hello. It is completely understandable to be worried when your child develops a fever while taking antibiotics.
Typically, antibiotics take about 48 to 72 hours to start taking full effect. Therefore, developing a fever after only a day and a half of medication is quite common and does not necessarily mean the medication is ineffective.
Current Assessment:
It is too early to determine whether the antibiotic is working or not.
With bronchitis, it is normal for a child's fever to fluctuate up and down for a few days.
The most important factor right now is your child's overall condition and activity level.
What You Should Do Now:
Continue administering the antibiotics exactly as prescribed. Do not skip doses.
You can give over-the-counter fever-reducing medication (antipyretics) if your child is uncomfortable or struggling due to the fever.
Ensure your child stays well-hydrated by offering plenty of fluids.
Keep a record of your child's condition, noting their temperature, cough frequency, and activity levels.
When to Seek Immediate Medical Attention:
If your child's breathing becomes rapid, heavy, or labored.
If the fever does not begin to subside after 3 full days of taking the antibiotic.
If the fever stays consistently above 40°C (104°F).
If your child completely refuses to eat or drink.
In most cases, you will start to see improvement after 2 to 3 days of treatment. It is safe to monitor your child at home until tomorrow. However, if you notice any concerning changes in their breathing or overall state, please do not hesitate to revisit your pediatrician for a thorough 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.
