Diarrhea is one of the most common side effects of antibiotics. The first step is to contact the doctor prescribing the antibiotic to ascertain the importance of the antibiotic, and whether there is a suitable alternative. If the antibiotic needs to be continued, one should ensure that the patient is suitably hydrated and rested.
Avoid milk and dairy products, as well as oily foods. Anti-diarrhea medication can help to improve the symptoms while the patient is undergoing treatment.
Another possibility is that the diarrhea and antibiotics are not related, and that there is a separate gut infection or other illness that is not treated by the antibiotic. If the diarrhea persists after the antibiotic course is completed, then you may want to see the doctor for further investigations. If the diarrhea is very severe, for example large volume and multiple times, associated with fever, severe pains or blood in stool, then you should not wait and immediate seek medical attention.
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