What's better for upset stomach with vomitting and diarrhea, warm or cold 7up? flat or carbonated?

Whatever works best for you.: The key when having an illness with both vomiting and diarrhea is to not get dehydrated. It really doesn't matter whether you drink 7-up or any liquid, whether flat or carbonated, as long as you're able to gets plenty of liquids. So you can experiment around to find out what works best for you. I would recommend that you not drink milk is your liquid of choice, however. Whatever you decide on, drink as much as you can, to avoid dehydration.If the vomiting is so severe that you can't keep any liquids down, then you may need to seek medical attention.