context: Every year, millions of Americans come down with the "stomach flu," or viral gastroenteritis. It can cause diarrhea, vomiting, cramps, fever, and headache. It's also highly contagious. What treatments will make life with the stomach flu a little less awful? More importantly, how can you avoid getting it in the first place? Here are some answers. The stomach flu is not a single disease. Instead, it's just a nickname for viral gastroenteritis, which is itself caused by a number of nasty viruses, such as noroviruses, rotaviruses, and adenoviruses. These viruses target the digestive tract and cause inflammation of the stomach and intestines. The most awful symptoms -- diarrhea, vomiting, and cramps -- are actually your body's defense mechanisms. Your body is trying to drive the virus out. Stomach flu can develop at any time of the year, but it's most common in the fall and winter in the U. S. Although unpleasant, stomach flu is rarely serious. Symptoms usually last for 1 to 3 days and sometimes longer. The greatest risk -- especially in babies and older people -- comes from dehydration. Untreated, dehydration can be dangerous. Despite the name, stomach flu has nothing to do with the "true" flu, influenza. Influenza causes body ache and fever. It almost never causes diarrhea or vomiting in adults. Rarely, it can trigger vomiting in children. There is no cure for the stomach flu. Antibiotics don't help, because it's caused by viruses, not bacteria. For the most part, you just have to wait it out. In the meantime, there are some things you can do to make yourself more comfortable and prevent complications. Drink more. It's important to increase fluid intake when you are vomiting or have diarrhea. Adults should aim to get one cup of fluid every hour. Children need 1 ounce of fluid every 30 to 60 minutes. Drink slowly, since too much at once could worsen vomiting. If your child tends to gulp, give her a frozen popsicle instead. Drink wisely. When you have diarrhea, drinking more water may not be enough. You're losing important minerals and electrolytes that water can't supply. Instead, ask your doctor about giving your sick child an oral rehydration solution such as Cera Lyte, Infalyte, Naturalyte, Pedialyte, and generic brands. ( If your baby is still nursing or using formula, keep feeding him as usual.) Adults can use oral rehydration solutions or diluted juices, diluted sports drinks, clear broth, or decaffeinated tea. Sugary, carbonated, caffeinated, or alcoholic drinks can make diarrhea worse, so be sure to dilute sugary beverages if you drink them. Don't eat only bland foods. The old advice was to stick with a liquid diet for a few days and then to add in bland foods, such as the BRAT diet of bananas, rice, applesauce, and toast. That's fine for the first day or so of stomach flu. However, doctors say that you should return to your normal diet as soon as you feel up to it. BRAT foods aren't bad. They just don't provide the fat and protein that you need. Sticking with them too long could actually slow your recovery. Get the right nutrients. Look for foods with potassium (such as potatoes, bananas, and fruit juices), salt (such as pretzels and soup), and yogurt with active bacterial cultures. Even a little fat could help, because it slows down digestion and may reduce diarrhea. If you feel up to it, add a pat of butter or some lean meat to your next meal. Use over-the-counter medications. They're not necessary, but some people find relief in medications for diarrhea and vomiting. Just use them with care, and read and follow the label instructions. Never give a medication for diarrhea or vomiting to a child unless a pediatrician says that you should. Rest. Give your body time to recover. The viruses that cause gastroenteritis come from contact with an infected person's stool. You may get it if a person with the virus didn't wash his hands after using the bathroom and then touched the escalator at the mall -- the same escalator you touched before eating lunch. Stomach flu viruses are tough, too. Some can live on surfaces such as counters for months. It's important to take steps to protect yourself and your family. Here's some advice. Wash your hands. According to experts, this is still the best way to stop a stomach virus. One review of studies found that good hand-washing technique cut the rate of diarrhea by 40%. Make sure to use soap and water and do it thoroughly -- wash your hands for as long as it takes to recite the alphabet. Always wash your hands after using the bathroom, before eating, and after changing a diaper. Use hand sanitizer. If you're not near a sink to wash your hands, use an alcohol-based hand sanitizer. Be aware that hand sanitizer may not be as effective as hand washing at preventing the stomach flu. Wipe down surfaces. If a family member has the stomach flu, wash off high-traffic areas -- such as the bathroom, door knobs, phones, and TV remotes -- with a diluted bleach solution. If it's possible, keep healthy people out of the bathroom the sick person is using. Make sure your kids get their vaccines. Vaccines for rotavirus can protect children from some types of stomach flu. Kids usually get the vaccines before they are age 2. Most people don't need to see the doctor when they have the stomach flu. But it's a good idea to get medical attention if you or your child has stomach flu and: Is under 3 months old Is over 3 months old and has been vomiting for more than 12 hours or the diarrhea hasn't gotten better after two days Is an adult and the diarrhea hasn't gotten a little better after two days Has other symptoms, such as high fever or blood or pus in the stool In rare cases, people with stomach flu need to be hospitalized, usually because of dehydration. In adults, dehydration can cause extreme thirst, decreased urination, dark urine, dry skin, fatigue, and dizziness. In babies and young children, dehydration can cause: Crying without tears Going three hours or more without a wet diaper Fever Dry tongue and mouth Extreme crankiness Sunken fontanel, the soft spot on the top of a baby's head Sunken cheeks or eyes Anyone with signs of dehydration needs medical help right away.