24-48 hours usually lasts.
I found this
Apple Cider Vinegar as Preventative Medicine
1 Reader has stopped food poisoning (bad chicken) by taking a shot (at least 1/8th cup or 2 TBLSP) of straight apple cider vinegar as soon as her stomach started to feel queasy. She writes, "It burned going down, but was remarkable in stopping my queasy stomach within 5 minutes. I am certain I did not get food poisoning because the apple cider vinegar quickly destroyed the bacteria in my colon and stomach. Amazing!"
We suggest that you drink straight apple cider vinegar the moment you feel you might have food poisoning. Better yet, take it before going to a barbeque, or any event that the food has been sitting around for a while.
Dosage: In the case of food poisioning, we recommend pasteurized Apple Cider Vinegar as it is extremely strong. Grocery stores will carry at least one, if not more, commercial brands of ACV. Heinz is a good brand, but any will do. DO NOT DILUTE IT. However, be prepared for your throat and stomach to burn!
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