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Why do antibiotics upset my stomach, and what helps?

Answered by the AskDoc Medical Team · Medically reviewed under our Medical Director, MBBS

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.

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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.

See rehydration salts

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