Survive This: Sudden Illness on the Trail

Beware of dehydration when a sudden illness strikes.

Predicament: You're two days into a weeklong trip when the mutiny in your bowels escalates to full-scale revolt. Now you can hardly walk–you're doubled over with intense stomach cramps, and suffering from explosive diarrhea, a mild fever, and nausea. How does a tortured hiker find relief?

Lifeline: Your gut is a battlefield, and whatever the marauding invader–virus, bacteria, or parasite–the treatment is the same. Your biggest concern is dehydration. Most bouts of infectious diarrhea subside within 72 hours, so camp near a reliable water source and wait it out. Steadily sip water, along with a diluted energy drink to replace electrolytes. (A teaspoon of salt and 4 tablespoons sugar in a liter of water is also a good rehydration solution.) Avoid excessive sugar in snacks, which inhibits water absorption. Have your catholes dug ahead of time, and wash your hands after you use them. If you have a high fever and bloody stool, don't take an antimotility agent like Imodium A-D, which can slow the purge of bad bacteria. You need an antibiotic. Reintroduce solid foods (the blander the better) as soon as symptoms start to ebb. Persistent fever, a swollen abdomen, and/or diarrhea for more than three days are signs of more serious trouble; evacuate and seek medical help.