May 26, 2021

Interviewer: How long until food poisoning takes effect? Dr. Troy Madsen's an emergency room physician. If I eat something questionable, when should I start noticing those symptoms if I got food poisoning?

Dr. Madsen: Food poisoning's going to take effect in about four to six hours. Let's say you're at a summer barbecue. There's some potato salad that's been sitting out for several hours in the 100-degree heat. You decide, "Oh why not, I'll try it." Two hours later, you feel fine. Well, you're not out of the woods yet. This is really going to kick in about four to six hours. Once you feel it, it should last about 12 hours and then typically will go away at that point.

Interviewer: Do I need medical attention if I feel that I have food poisoning?

Dr. Madsen: Not necessarily. The big concern would be if you feel really dehydrated, you can't keep anything down. You may need IV fluids. You may need some nausea medication. If this just keeps going on beyond 12 hours, you have to think of other causes of this that could be more serious.


updated: May 26, 2021
originally published: June 18, 2019

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