Discusses the decision about when to start dialysis. Includes what kidney failure is, the treatment for it, and reasons why you might or might not want to start dialysis. Includes interactive tool to help you make your decision.

Discusses procedure (also called EGD or esophagogastroduodenoscopy) used to check the esophagus, stomach, and upper small intestine for problems. Covers why it is done, how it is done, and how it feels. Discusses what results could mean. Looks at risks.

Anoscopy, proctoscopy, and sigmoidoscopy tests allow your doctor to look at the inner lining of your anus, your rectum, and the lower part of the large intestine (colon). These tests are used to look for abnormal growths (such as tumors or polyps), inflammation, bleeding, hemorrhoids, and other conditions (such as...

Guides you through choosing a test to check for colorectal cancer. Looks at symptoms of colorectal cancer. Covers stool tests, sigmoidoscopy, colonoscopy, and virtual colonoscopy. Includes interactive tool to help you make your decision.

A prolactin test measures the level of the hormone prolactin, which is made by the pituitary gland, in your blood. Pregnant women have high levels of prolactin, which helps make breast milk. During pregnancy, prolactin levels increase by 10 to 20 times. After the baby is born, prolactin stays high if you are...

A chemistry screen is a blood test that measures the levels of several substances in the blood (such as electrolytes). A chemistry screen tells your doctor about your general health, helps look for certain problems, and finds out whether treatment for a specific problem is working. Some chemistry screens look at more...

Explains liver biopsy, also called percutaneous liver biopsy, a test used to look for liver diseases like hepatitis, cirrhosis, hemochromatosis, and cancer. Covers how to prepare and what to expect. Includes what results mean. Also lists risks.

Marijuana, also called cannabis, is a drug that's made of the leaves, flowers, and buds of the cannabis plant. Medical marijuana can help treat symptoms like pain, nausea, and lack of appetite. It may be used by people who have health problems like cancer, AIDS, or multiple sclerosis. Is medical marijuana helpful and...

An alkaline phosphatase (ALP) test measures the amount of the enzyme ALP in the blood. ALP is made mostly in the liver and in bone with some made in the intestines and kidneys. It also is made by the placenta during pregnancy. The liver makes more ALP than the other organs or the bones. Some conditions cause large...

Laparoscopy (say "lap-uh-ROSS-kuh-pee") is a type of surgery that uses very small cuts. These cuts are called incisions. The doctor puts a lighted tube through incisions in your belly. This tube is called a scope. Then the doctor puts special tools through the tube to do the surgery. The surgery may be done to diagnose...

Cardiac enzyme studies measure the levels of enzymes and proteins that are linked with injury of the heart muscle. The test checks for the proteins troponin I (TnI) and troponin T (TnT). If your heart muscle is injured, such as from a heart attack, troponin proteins leak out of damaged heart muscle cells, and their...

Clostridioides difficile (C. diff) are bacteria that live in your large intestine, or colon, all the time. They usually don't cause problems. But sometimes, something causes the bacteria to grow. When there are too many of them, they release harmful substances called toxins. When the toxins are released, the colon...

A test for catecholamines measures the amount of the hormones epinephrine, norepinephrine, and dopamine in the blood. These catecholamines are made by nerve tissue, the brain, and the adrenal glands. Catecholamines help the body respond to stress or fright and prepare the body for "fight-or-flight" reactions. The...

Covers the various types of prostatitis, including acute bacterial, inflammatory, noninflammatory, and chronic pelvic pain syndrome. Covers symptoms for each type. Discusses treatment for each type. Covers lifestyle changes, medicines, and surgery.

Covers the causes and symptoms of juvenile idiopathic arthritis, also called juvenile rheumatoid arthritis. Looks at treatment with NSAIDs, physical therapy, and possibly shots of steroid medicine. Includes tips for helping your child cope with JIA.

A gastrin test measures the level of the hormone gastrin in the blood. Gastrin is produced by cells, called G cells, in the stomach lining. When food enters the stomach, G cells trigger the release of gastrin in the blood. As blood levels of gastrin rise, the stomach releases acid (gastric acid) that helps break down...

Describes pancreatic cancer. Talks about symptoms and what tests are used to diagnose it. Provides treatment details. Lists factors that raise your risk.

An adrenocorticotropic hormone test measures the level of adrenocorticotropic hormone (ACTH) in the blood to check for problems with the pituitary gland and adrenal glands. ACTH is made in the pituitary gland in response to the release of another hormone, called corticotropin-releasing hormone (CRH), by the...

Partial thromboplastin time (PTT) is a blood test that measures the time it takes your blood to clot. A PTT test can be used to check for bleeding problems. Blood clotting factors are needed for blood to clot (coagulation). The partial thromboplastin time is an important test because the time it takes your blood to clot...

A renin assay blood test is done to find the cause of high blood pressure (hypertension). Renin is an enzyme made by special cells in the kidneys. Renin works with aldosterone (a hormone made by the adrenal glands) and several other substances to help balance sodium and potassium levels in the blood and fluid levels in...

A prostate biopsy is a test to remove small samples of prostate tissue to be looked at under a microscope. The tissue samples taken are looked at for cancer cells. For a transrectal prostate biopsy, an ultrasound probe is inserted into the rectum. Guided by ultrasound, a spring-loaded needle is used to take samples from...

A cortisol test is done to measure the level of the hormone cortisol in the blood. The cortisol level may show problems with the adrenal glands or pituitary gland. Cortisol is made by the adrenal glands. Cortisol levels go up when the pituitary gland releases another hormone called adrenocorticotropic hormone (ACTH)...

DHEA-S (dehydroepiandrosterone sulfate) is a male hormone (androgen) that is made in the adrenal glands. The body turns it into testosterone. A test for DHEA-S checks the level of this hormone in the blood. Testosterone affects sexual features and development. In men, it is made in large amounts by the testicles. In...

The overnight dexamethasone suppression test checks to see how taking a steroid medicine called dexamethasone changes the levels of the hormone cortisol in the blood. This test checks for a condition in which large amounts of cortisol are produced by the adrenal glands ( Cushing's syndrome). Normally, when the pituitary...

A comprehensive metabolic panel is a blood test that measures your sugar (glucose) level, electrolyte and fluid balance, kidney function, and liver function. Glucose is a type of sugar your body uses for energy. Electrolytes keep your body's fluids in balance. They also help keep your body working normally, including...