H2-Blockers
Medicines that reduce the amount of acid the stomach produces. They block histamine2 (HIH-stuh-min-too). Histamine signals the stomach to make acid. Prescription H2-blockers are cimetidine (suh-MEH-tuh-deen) (Tagamet), famotidine (fuh-MAH-tuh-deen) (Pepcid), nizatidine (nih-ZAH-tuh-deen) (Axid), and ranitidine (ruh-NIH-tuh-deen) (Zantac). They are used to treat ulcer symptoms. Nonprescription H2-blockers are Zantac 75, Axid AR, Pepcid-AC, and Tagamet-HB. They are for GERD, heartburn, and acid indigestion.

Heartburn
A painful, burning feeling in the chest. Heartburn is caused by stomach acid flowing back into the esophagus. Changing the diet and other habits can help to prevent heartburn. Heartburn may be a symptom of GERD. See also Gastroesophageal Reflux Disease (GERD).
- Tips to control heartburn
- Avoid foods and beverages that affect lower esophageal sphincter pressure or irritate the esophagus lining.
- Lose weight if overweight.
- Stop smoking.
- Elevate the head of the bed 6 inches.
- Avoid lying down 2 to 3 hours after eating.
- Take an antacid.

Helicobacter pylori (H. pylori)
A spiral-shaped bacterium found in the stomach. H. pylori damages stomach and duodenal tissue, causing ulcers. Previously called Campylobacter pylori.

Hemochromatosis
A disease that occurs when the body absorbs too much iron. The body stores the excess iron in the liver, pancreas, and other organs. May cause cirrhosis of the liver. Also called iron overload disease.

Hemorrhoidectomy
An operation to remove hemorrhoids.

Hemorrhoids
Swollen blood vessels in and around the anus and lower rectum. Continual straining to have a bowel movement causes them to stretch and swell. They cause itching, pain, and sometimes bleeding.

Hepatic
Related to the liver.

Hepatic Coma
See Hepatic Encephalopathy.

Hepatic Encephalopathy
A condition that may cause loss of consciousness and coma. It is usually the result of advanced liver disease. Also called hepatic coma.

Hepatitis
Irritation of the liver that sometimes causes permanent damage. Hepatitis may be caused by viruses or by medicines or alcohol. Hepatitis has the following forms:

Hepatitis A
A virus most often spread by unclean food and water.

Hepatitis B
A virus commonly spread by sexual intercourse or blood transfusion, or from mother to newborn at birth. Another way it spreads is by using a needle that was used by an infected person. Hepatitis B is more common and much more easily spread than the AIDS virus and may lead to cirrhosis and liver cancer.

Hepatitis C
A virus spread by blood transfusion and possibly by sexual intercourse or sharing needles with infected people. Hepatitis C may lead to cirrhosis and liver cancer. Hepatitis C used to be called non-A, non-B hepatitis.

Hepatitis D (Delta)
A virus that occurs mostly in people who take illegal drugs by using needles. Only people who have hepatitis B can get hepatitis D.

Hepatitis E
A virus spread mostly through unclean water. This type of hepatitis is common in developing countries. It has not occurred in the United States.

Hepatitis B Immunoglobulin (HBIg)
A shot that gives short-term protection from the hepatitis B virus.

Hepatitis B Vaccine
A shot to prevent hepatitis B. The vaccine tells the body to make its own protection (antibodies) against the virus.

Hepatologist
A doctor who specializes in liver diseases.

Hepatology
The field of medicine concerned with the functions and disorders of the liver.

Hepatotoxicity
How much damage a medicine or other substance does to the liver.

Hernia
The part of an internal organ that pushes through an opening in the organ's wall. Most hernias occur in the abdominal area.

Herniorrhaphy
An operation to repair a hernia.

Hiatal Hernia (Hiatus Hernia)
A small opening in the diaphragm that allows the upper part of the stomach to move up into the chest. Causes heartburn from stomach acid flowing back up through the opening. See also Diaphragm.

Hirschsprung's Disease
A birth defect in which some nerve cells are lacking in the large intestine. The intestine cannot move stool through, so the intestine gets blocked. Causes the abdomen to swell. See also Megacolon.

Hormone
A substance in the body that regulates certain organs. Hormones such as gastrin help in breaking down food. Some hormones come from cells in the stomach and small intestine.

Hydrochloric Acid
An acid made in the stomach. Hydrochloric acid works with pepsin and other enzymes to break down proteins.

Hydrogen Breath Test
A test for lactose intolerance. It measures breath samples for too much hydrogen. The body makes too much hydrogen when lactose is not broken down properly in the small intestine.

Hyperalimentation
See Parenteral Nutrition.

Hyperbilirubinemia
Too much bilirubin in the blood. Symptoms include jaundice. This condition occurs when the liver does not work normally. See also Jaundice.