Why do antibiotics upset my stomach, and what helps?
Antibiotics clear infection but also thin out the gut's resident bacteria, so loose stools, cramps and nausea are common passengers. Taking doses with food, when the label allows, softens much of it.
Specific probiotic strains taken during the course modestly reduce antibiotic diarrhea; yogurt and kefir are reasonable food versions.
Finish the course unless your prescriber says otherwise. Severe watery diarrhea, fever or blood during or in the weeks after antibiotics needs prompt review, as a C. difficile infection must be ruled out.
Source: NHS, diarrhea and vomiting
See a doctor promptly if
- Difficulty breathing, chest pain, or breathing so fast you cannot finish a sentence
- A stiff neck with fever and headache, a rash that does not fade when pressed with a glass, or new confusion
- Unable to swallow your own saliva, drooling, or a muffled voice with severe throat pain
- Fever with shivering rigors plus back or flank pain and burning on passing urine
- Spreading redness, swelling and heat around a wound, or a red streak tracking up a limb
- Severe watery or bloody diarrhea during or in the weeks after an antibiotic course
Try the symptom diary10 seconds a day, free, nothing to installGut symptoms travel with food, stress and timing, and nobody reconstructs that from memory.
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Answered by the AskDoc Medical Team · Medically reviewed under our Medical Director, MBBS · How we review
For vomiting or diarrhea
Rehydration salts replace fluid better than water or sports drinks. Keep a few sachets at home; nobody wants to shop for them while sick.
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