Gastroenteritis symptoms: Some people also have other

Some people also have other symptoms, such as a loss of appetite, an upset stomach, aching limbs and headaches. The symptoms usually appear up to a day after becoming infected. They typically last less than a week, but can sometimes last longer. The diagnosis of gastroenteritis is usually obvious from the symptoms alone, but doctors consider other gastrointestinal disorders that cause similar symptoms (for example, ulcerative colitis). Gastroenteritis - Learn about the causes, symptoms, diagnosis & treatment from the Merck Manuals - Medical Consumer Version. Learn about gastroenteritis (stomach flu), its symptoms, causes, and types. Discover effective treatment options to manage and recover from this common digestive condition.