You may get resistant bacteria in your bowel during travel and they can subsequently become a problem. If you develop an infection caused by these resistant bacteria it can be hard to treat because not many antibiotics will be effective against them. We have recently learnt that many people going to some destinations such as India and Egypt acquire resistant bacteria. If you get diarrhoea while away the rate of acquisition is higher and taking antibiotics to treat diarrhoea increases the risk further. We are thus discouraging people from taking antibiotics for diarrhoea unless the diarrhoea is severe. It is also worth telling your doctor you have recently travelled if you need to have surgery or get an infection as first line antibiotics may not work.