Haha... when I say diarrhea, I'm talking liquid poop. Like you are peeing out of your bum! For me, it always starts suddenly, usually in the middle of the night, so I immediately begin a BRAT (bananas, rice, applesauce, toast) diet the next day and only drink electrolyte water, tea, and fresh coconut or guava juice. But, if it lasts more than 2-3 days without noticable improvement, then I take 500mg Azithromycin once a day for 3 days. I take it in conjunction with Loperamide (Imodium), 4mg after initial "day 3" diarrhea (when I also take the first Azithromycin) and 2mg each diarrhea thereafter, not exceeding 16mg per day over a course of 2 days. That always resolves it within 2 or 3 days.
The detail above is for others who come across this thread and may be looking for a solution. I certainly agree with all the prior posts, including the person who seems to do something similar to my regiment above, the person concerned about antibiotic resistance, and the person talking about sanitation and food safety issues. Such a complex issue to navigate!
Hats off to you guys who lived in SE Asia 20+ years and never, or rarely, had to deal with this issue! 🙏💩💧