Nausea

Nausea is an unpleasant, diffuse sensation of unease and discomfort, often perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged, and has been described as placing discomfort on the chest, upper abdomen, or back of the throat. Nausea is an unpleasant, diffuse sensation of unease and discomfort, often perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged, and has been described as placing discomfort on the chest, upper abdomen, or back of the throat. Nausea is a non-specific symptom, which means that it has many possible causes. Some common causes of nausea are gastroenteritis and other gastrointestinal disorders, food poisoning, motion sickness, dizziness, migraine, fainting and low blood sugar. Nausea is a side effect of many medications including chemotherapy, or morning sickness in early pregnancy. Nausea may also be caused by anxiety, disgust and depression. Medications taken to prevent and treat nausea are called antiemetics. The most commonly prescribed antiemetics in the US are promethazine, metoclopramide and the newer, extremely effective ondansetron. The word nausea is from Latin nausea, from Greek ναυσία – nausia, 'ναυτία' – nautia, motion sickness, 'feeling sick or queasy'. Gastrointestinal infections (37%) and food poisoning are the two most common causes of acute nausea and vomiting. Side effects from medications (3%) and pregnancy are also relatively frequent. There are many causes of chronic nausea. Nausea and vomiting remain undiagnosed in 10% of the cases. Aside from morning sickness, there are no gender differences in complaints of nausea. After childhood, doctor consultations decrease steadily with age. Only a fraction of one percent of doctor visits by those over 65 are due to nausea. Gastrointestinal infection is one of the most common causes of acute nausea and vomiting. Chronic nausea may be the presentation of many gastrointestinal disorders, occasionally as the major symptom, such as gastroesophageal reflux disease, functional dyspepsia, gastroparesis, peptic ulcer, celiac disease, non-celiac gluten sensitivity, Crohn's disease, hepatitis, upper gastrointestinal malignancy, and pancreatic cancer. Uncomplicated Helicobacter pylori infection does not cause chronic nausea. Food poisoning usually causes an abrupt onset of nausea and vomiting one to six hours after ingestion of contaminated food and lasts for one to two days. It is due to toxins produced by bacteria in food. Many medications can potentially cause nausea. Some of the most frequently associated include cytotoxic chemotherapy regimens for cancer and other diseases, and general anaesthetic agents. An old cure for migraine, ergotamine, is well known to cause devastating nausea in some patients; a person using it for the first time will be prescribed an antiemetic for relief if needed. Nausea or 'morning sickness' is common during early pregnancy but may occasionally continue into the second and third trimesters. In the first trimester nearly 80% of women have some degree of nausea. Pregnancy should therefore be considered as a possible cause of nausea in any women of child bearing age. While usually it is mild and self-limiting, severe cases known as hyperemesis gravidarum may require treatment. A number of conditions involving balance such as motion sickness and vertigo can lead to nausea and vomiting.