Usually you're looking at 24-48 hours but if you only ate a bit it might be less.. Drink up and try to get some sort of electrolyte drink into you. Also white rice can help to bind things together. Fruit makes it worse.
If your income depends on it then you could try immodium but it's not good because your body needs to get the toxins out as fast as it can and immodium interferes with that.
I was just looking at a pack of gastro stop I have here that we took to Bali and thankfully never needed, but it say on the pack that it provides improvement from the runs within 1 - 3 hours. Maybe a couple of doses will help you by tomorrow.
Imodium is a medicine that stops gastro. It's not that great because it can prolong it but it can help in the short term if you really have to be somewhere. I think there are other anti-diarrhea medicines. A chemist should be able to recommend the best one if you need one.
I'm not sure if pasta would be the same as rice. Some people say that drinking the water you cook the rice in helps.
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