Category: A

A rapid allergic reaction that can be life-threatening. Anaphylaxis is an acute systemic type of allergic reaction that affects the entire body. During an anaphylactic reaction, the immune system releases antibodies and the tissues release substances such as histamine, which causes the airways to narrow, resulting in wheezing and labored breathing. Histamine also causes the…

Narrowing of the anus, which is also known as anal stricture. In this condition, the anal opening is too small to permit the normal passage of feces. Symptoms of anal stenosis include constipation and pain during defecation. In many cases, anal stenosis is present from birth. Sometimes, it is the result of inflammatory bowel DISEASE…

Secretion of substances, such as blood, mucus, or pus, from the anus. Anal discharge is often the result of a relatively minor problem, such as hemorrhoids or an anal fissure (a tear or ulcer in the lining of the anal canal). However, in some cases, a discharge may be the sign of a more serious…

The widening of the anal sphincter muscle to treat hemorrhoids or to repair an anal fissure, a tear or ulcer in the lining of the anal canal. It is also performed if there is a narrowing of the anal canal that interferes with the normal passage of stools. The procedure can stop the pain, spasms,…

A chart used to detect a type of age-related change in central vision known as macular degeneration. The chart looks like a piece of paper with dark lines forming a square grid around a dot in the center. The grid is held at a comfortable reading distance with one eye covered while the person focuses…

A procedure used during labor in which saline (a salt solution that has the same concentration as body fluids) is instilled into the uterus at a constant rate. The objectives of this treatment include flushing out thick waste-stained fluid and reversal of abnormal fetal heart rate patterns, which may be related to umbilical cord compression.…

Dental surgery to trim or remove the bone or gum tissue in the jawbone that holds the roots of the teeth. The procedure is usually performed along with tooth extractions. Dental surgery to trim or remove the bone or gum tissue in the jawbone that holds the roots of the teeth. The procedure is usually…

Another name for vitamin E. Alpha-tocopherol may protect cells from some kinds of damage and helps slow the cell damage that happens naturally as a person ages. Vitamin E is thought to interfere with the oxygen-controlled signals that make cancer cells grow. Vitamin E is found naturally in nuts, sunflower seeds, mayonnaise, cold-pressed vegetable oils,…

Drugs that help lower blood pressure by preventing blood vessels from constricting. Alpha blockers work by preventing stress hormones from stimulating receptors in the blood vessels, thereby preventing arteries and veins from constricting, which is what raises blood pressure. Drugs that help lower blood pressure by preventing blood vessels from constricting. Alpha blockers work by…

Dried juice of the leaves from various species of lilac plants. Aloe, or aloe vera, is chiefly used to ease the pain of sunburn, frostbite, and other skin irritations, but the natural medicine is not regulated by the Food and Drug Administration. The dried juice of one of several species of plants of the genus…