I got mad food poisoning a couple of years ago while traveling in Asia. I hoped it would pass on its own and took nothing for a few days. The flight across the Paciific was hell, it was delayed, I missed my puddle jumper from LAX to Santa Barbara, and the airline put me up in a fancy hotel for the night as I suffered.
When I got home I had my girlfriend take me to the store to buy the Pepto and clear liquids. I then camped out between the toilet and my couch for two more days.
I couldn't keep anything in me, my eyes sunk in, and I was in pain. When I tried to get off the couch and my legs cramped up and I couldn't move, I decided it was time to go to the ER (2am).
They told me Pepto was useless and suggested the Immodium. In the meantime, they gave me morphine. That stuff is amazing!!!! All the pain, cramps, and urges went away in seconds.
Got morphine?
I never, never, never travel in Asia anymore without the Immodium. My Lonely Planet tells me not to take it, but I do it anyway. Good stuff.