Nausea

Nausea is a general term describing a queasy stomach, with or without the feeling that you are about to vomit. Almost everyone experiences nausea at some time, making it one of the most common problems in medicine. Nausea is not a disease, but a symptom of many different disorders. It is caused by problems in any one of three parts of the body, including:  

• Abdominal and pelvic organs — Many different abdominal conditions can cause nausea. Common abdominal causes of nausea include inflammation of the liver (hepatitis) or pancreas (pancreatitis); a blocked or stretched intestine or stomach; gastroesophageal reflux (GERD); irritation of the stomach, intestinal lining, appendix or pelvic organs; inflammation of the kidney; and gallbladder problems. The most common abdominal illnesses that result in nausea are viral infections (gastroenteritis). Nausea also can be caused by constipation and normal menstruation.  
• Brain and spinal fluid  —  Nausea is common with migraine headaches, head injury, brain tumors, stroke, bleeding into or around the brain and meningitis (inflammation or infection of the membranes covering the brain). It can be a symptom of glaucoma, resulting from pressure on the nerves at the back of the eye. It sometimes is a brain reaction triggered by pain, significant emotional distress or exposure to unpleasant sights or odors.  
• Balance centers in the inner ear — Nausea can be related to vertigo, a dizzy sensation of spinning, moving or falling when you are not moving. Common conditions that cause vertigo include motion sickness (triggered by repeated movements in different directions inside a car, boat, train, plane or amusement ride), viral infections of the inner ear (labyrinthitis), sensitivity to position change (benign positional vertigo) and certain brain or nerve tumors.  

Nausea also is a common side effect of some body chemical changes:  

• Reproductive hormones — About 50% of women experience morning sickness during the first few months of pregnancy, and it is a common side effect of birth control pills.  
• Medications — Many medicines (including prescription, over-the-counter and herbal medicines) commonly cause nausea as a side effect, especially when more than one medication is taken at the same time. Chemotherapy drugs and antidepressants are among the medicines that frequently cause nausea.  
• Low blood sugar — Nausea is common with low blood sugar.  
• Alcohol use — Both alcohol intoxication and alcohol withdrawal, including a hangover, can cause nausea. 
• Anesthesia — Some people experience nausea while awakening from surgery and recovering from anesthesia.  
• Food allergies and food poisoning — In food poisoning, small amounts of bacteria in contaminated food produce irritating toxins that cause nausea and abdominal cramps.  

Symptoms

Nausea is difficult for many people to describe. It is a very uncomfortable, but not painful, feeling that is felt in the back of the throat, the chest or the upper abdomen. The feeling is associated with distaste for food or an urge to vomit. When the body prepares to vomit, the following sequence may occur:  

• The muscular ring between the esophagus and stomach (esophageal sphincter) relaxes.  
• The abdominal muscles and diaphragm contract.  
• The windpipe (larynx) closes.  
• The lower portion of the stomach contracts.  

When a person vomits, the stomach contents are expelled through the esophagus and mouth.  

As a result of these body actions, when you have nausea you experience retching. Retching is repeated rhythmic contractions of respiratory and abdominal muscles that occur without your control. You may or may not vomit. Profuse sweating sometimes accompanies nausea.  

Diagnosis

Because nausea occurs for such a wide variety of reasons, your doctor will seek clues to the cause of nausea in your medical history, including your medication use. It is especially helpful for you to report other symptoms that you might be having, or activities (such as eating) that trigger your nausea. If you are a sexually active woman of childbearing age, tell your doctor whether there is a possibility that you could be pregnant, the date of your last menstrual period and any type of birth control you use. 

Your doctor will examine you. The exam may include blood pressure testing, an abdominal examination, neurological examination or other tests, depending on your recent symptoms and other medical history. Blood tests may be done. For any woman who could be pregnant, a pregnancy test should be done. If you have had a recent head injury, you may require a brain imaging test, such as a computed tomography (CT) scan. 

Expected Duration

The cause of nausea will determine how long it lasts or how often it occurs. When the cause can be traced to spoiled food, motion sickness or a viral illness, nausea is usually short lived and should not be a cause for concern. In most cases, the queasy feeling lasts no more than minutes to a few hours and usually goes away on its own within 24 hours. 

Prevention

Some causes of nausea are not easily prevented. While the cause of your nausea is being determined, you can minimize episodes of nausea by following some basic guidelines:  

• Eat small meals every few hours so your stomach won't feel full.  
• Try to avoid bothersome odors such as perfume, smoke or certain cooking smells.  
• If you have had nausea for weeks to months, consider keeping a food diary to help identify foods that cause nausea.  
• Avoid eating any food that smells or appears spoiled or has not been refrigerated properly.  
• If you are prone to motion sickness, avoid reading in a moving vehicle. Also, try to sit in the part of the vehicle with the least movement (near the wings of an airplane or in the center of a boat). Ask your doctor about taking anti-nausea drugs before traveling.  
• Avoid alcohol.  
• If you take medications for nausea, including over-the-counter types, avoid drinking alcohol which may make you more ill. Always read the label before taking anti-nausea medication, because some motion sickness medications can cause significant drowsiness.  

Treatment

Nausea does not always require treatment, but sometimes treatment is helpful. There are several things you can do on your own to help, including:  

• Drink beverages that settle the stomach, such as ginger ale or chamomile tea.  
• Avoid caffeinated colas, coffees and teas.  
• Drink clear liquids to avoid dehydration (if vomiting is associated with nausea).  
• Eat small, frequent meals to allow the stomach to digest foods gradually.  
• Eat foods that are bland and simple for your stomach to digest, such as crackers or unbuttered bread, rice, chicken soup and bananas.  
• Avoid spicy foods and fried foods. 

Some over-the-counter medications can help to relieve nausea, including: 

• Chewable or liquid antacids, bismuth sub-salicylate (Pepto-Bismol) or a solution of glucose, fructose and phosphoric acid (Emetrol). These medicines help by coating the stomach lining and neutralizing stomach acid.  
• Dimenhydrinate (Dramamine) or meclizine hydrochloride (Bonine, Dramamine II). These medications are helpful for treating or preventing motion sickness and are thought to block receptors in the brain that trigger vomiting.  

If you continue to feel nauseated, several prescription medications are available to help relieve nausea. Most anti-nausea medicines have drowsiness as a side effect. Women who are pregnant, or who think they might be pregnant, should be evaluated by a physician before taking any drug, including over-the-counter medicines.  

When To Call A Professional

You should call your doctor if nausea lasts for more than three days. You should contact your doctor sooner if your nausea is associated with:  

• Recent head injury  
• Severe headache  
• Severe abdominal pain  
• Vomiting blood  
• Extreme weakness  
• High fever (over 101° Fahrenheit)  
• Blurred vision or eye pain  
• Confusion or stiff neck  

Prognosis

The outlook depends on the cause of the nausea. Most people recover completely within a few hours or a day.