Getting sick on a holiday is always a major disappointment and in a strange environment can be very difficult to cope with. A few simple preparations can reduce the likelihood of disaster.
If you are going overseas, find out what the conditions are like in the country or countries you will be visiting. You should ask about the climate, the food, any local diseases against which you should be immunised, and the availability and cost of medical treatment.
The most common ailment affecting overseas travellers is diarrhoea. Bali belly, Delhi belly, Cairo colic, Montezuma's revenge — the names are rueful testimony to the numbers of tourists whose main familiarity with their holiday destination is its lavatory facilities. Mostly diarrhoea is caused by contaminated water resulting from inadequate water and sewerage systems. Sometimes just the fact that you are drinking water that is different from the water you are used to, with different bugs in it, is enough to trigger a revolt in your intestines. If you are travelling in any third-world or tropical country, you should avoid drinking the water unless it has been boiled. Most reasonable hotels will provide a jug of boiled water in your room, but that still leaves the water you use to clean your teeth and ice blocks in all the long cool drinks you will undoubtedly consume. Don't have ice in your drinks, if necessary add mineral water from a bottle or can, and use boiled water to clean your teeth. If this is not possible, there are tiny purifying tablets you can pop into a glass, but these will give the water a 'taste' (which you may be able to overcome with a small sachet of fruit flavoured powder).
Food too can be a source of diarrhoea and food poisoning. Tempting as it is to try all those exotic dishes, steer clear of raw or underdone meat, uncooked seafood, unprocessed dairy products and uncooked fruits, vegetables and salad ingredients.
An attack of diarrhoea usually lasts only from one to three days but, especially if you are travelling around, it can be very uncomfortable and embarrassing. Ask your doctor to prescribe antidiarrhoea tablets before you go, and keep them with you in your personal baggage. If you are struck down with an attack, go on a fluid only diet for 24 hours and eat lightly for several days. You may have stomach pains, nausea and possibly vomiting as well.