Brief Answer: may cause additional diarrhoea Detailed Answer: HI, thanks for using healthcare magic The most common cause for diarrhoea and vomiting is infection either viral or bacterial. Zofran (ondansetron) is most commonly used for nausea and vomiting related to surgery, chemotherapy, radiation treatment. It has been recently been used to help persons with acute gastroenteritis with mainly vomiting. The possible complication would be diarrhoea, this is a possible side effect of this medication. This means it could potentially worsen your present diarrhoea. You may want to consider the use of over the counter pepto bismol , this is helpful for both diarrhoea and vomiting. The usual dose in adults is 2 tablets every 30 minutes as needed, to a maximum of 16 tablets in a 24 hour period. In addition, you may want to avoid solid food for today,concentrate on maintaining your fluid volume. This means taking small amounts of fluid frequently throughout the day, if you use a lot of fluid at one time, it will likely cause vomiting. Probiotics either on their own or yogurt, would also help to shorten the course of the illness. After 4 hours with no vomiting or diarrhoea, you can start using solid foods. I hope this helps, feel free to ask any additional questions

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