We have all had it at times.. not pleasant and over the years I've learned that the first feeling of that uncomfortable feeling in stomach and bowels should be immediately greeted with an armoured phalanx of medicine.
I've used Norfloxacin allot which does work well however following recent trip to China I came down with something a bit more stubborn and only high doses of Tetracycline seemed to be it nemesis.
Not a big fan of chemical corks so to speak as they seem to only treat the symptoms and not kill the bugs. Of course high does of tetracycline mean you are likely to have a very red sunburned face after a ride however thats acceptable.
Just interested in what you are packing in your kit when you go away to guard/ treat intestinal upsets .
I read somewhere that some Amazonian or remote tribe would insert freshly peeled taro root in their nether regions as a remedy however perhaps that one is not for me.