If you have a good relationship with your healthcare provider, ask for a 3 to 5 day course of Cipro to take with you on your travels in high risk areas. May save a vacation. I am generally not a fan of antibiotics but I keep Cipro in my first aid travel kit.
As a word to the wise, check out the CDC's recommendation for SE Asia. Most intestinal bugs there are Cipro resistant (thank you India), Z-Pak (azitromycin) is the drug of choice.
If you believe in 'take-no-prisoners', levofloxacin (described to me as Cipro in a black leather jacket) is the drug of choice outside of SE Asia.