Health Library

Category: Hormones

A1c Test
Covers blood test that checks the amount of sugar (glucose) bound to hemoglobin. Explains that test is done to check how well you are managing your diabetes. Covers how it is done and discusses results.

Abnormal Uterine Bleeding
What is abnormal uterine bleeding? Abnormal uterine bleeding is irregular bleeding from the uterus. It may be bleeding that is heavier, lighter, or lasts longer than your usual period. Or it may be bleeding that doesn't occur at your regular time. Let your doctor know if your bleeding is different than usual. They can...

Abnormal Uterine Bleeding: Should I Have a Hysterectomy?
Guides through decision to treat abnormal uterine bleeding. Explains symptoms that doctor would look for before recommending treatment. Covers benefits and risks. Includes an interactive tool to help you make your decision.

Addison's Disease
What is Addison's disease? Addison's disease develops when the adrenal glands, which are above the kidneys, are not able to make enough of the hormones cortisol and, sometimes, aldosterone. Your body needs both of these hormones to work as it should. Cortisol helps the body cope with extreme physical stress from...

Adrenocortical Carcinoma Treatment (PDQ®): Treatment - Patient Information [NCI]
Adrenocortical carcinoma is a rare disease in which malignant (cancer) cells form in the outer layer of the adrenal gland. . There are two adrenal glands. The adrenal glands are small and shaped like a triangle. One adrenal gland sits on top of each kidney. Each adrenal gland has two parts. The outer layer of the...

Adrenocorticotropic Hormone (ACTH) Test
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...

Aldosterone in Blood Test
An aldosterone test measures the level of aldosterone (a hormone made by the adrenal glands), in the blood. Aldosterone helps regulate sodium and potassium levels in the body. This helps control blood pressure and the balance of fluids and electrolytes in the blood. The kidney hormone renin normally stimulates the...

Aldosterone in Urine Test
An aldosterone test measures the level of aldosterone (a hormone made by the adrenal glands) in the urine. Aldosterone helps regulate sodium and potassium levels in the body. This helps control blood pressure and the balance of fluids and electrolytes in the blood. The kidney hormone renin normally stimulates the...

Amylase Test
An amylase test measures the amount of this enzyme in a sample of blood taken from a vein or in a sample of urine. Normally, only low levels of amylase are found in the blood or urine. But if the pancreas or salivary glands become damaged or blocked, more amylase is usually released into the blood and urine. In the...

Anabolic Steroids
What are anabolic steroids? Anabolic steroids are substances that are like the hormone testosterone. They are made in a lab. Doctors prescribe them to treat problems such as delayed puberty and problems that cause the body to make very low amounts of testosterone. They can cause puberty to start and can help some boys...

Antithyroid Antibody Tests
Thyroid antibody tests measure the levels of antibodies that can destroy thyroid tissue or make the cells produce thyroid hormones. They are blood tests. Antibodies that destroy thyroid tissue can lead to hypothyroidism (underactive thyroid). Antibodies that make the cells produce thyroid hormone can lead to...

Basic Metabolic Panel
Briefly discusses basic metabolic panel, a blood test that measures your sugar (glucose) level, electrolyte and fluid balance, and kidney function. Provides links to more info on specific tests such as blood urea nitrogen, creatinine, and potassium tests.

Bioidentical Hormones
Bioidentical hormones are made in a lab. They are based on compounds found in plants. They have the same structure as the hormones your body makes. Many commonly prescribed forms of estrogen and progesterone are bioidenticals. Some examples include Estrace and Prometrium. These types are approved and regulated by the...

Blood Glucose Test
Discusses blood glucose tests used to diagnose diabetes and prediabetes. Covers types of tests, including fasting blood sugar, 2-hour postprandial blood sugar, random blood sugar, and oral glucose tolerance. Discusses how to prepare and what results mean.

Brain Natriuretic Peptide (BNP) Test
Gives info on test for BNP hormone to tell how well the heart works. Tells how BNP checks for heart failure. Tells how to get ready for test. Includes what results mean. Also discusses things that affect test results, such as some health problems and medicines.

C-Peptide Test
Discusses C-peptide test, used to tell the difference between type 1 and type 2 diabetes, find the cause of hypoglycemia, or check whether a pancreas tumor (insulinoma) was completely removed. Discusses how the test is done and how to prepare for it.

Calcium (Ca) in Blood Test
A test for calcium in the blood checks the calcium level in the body that is not stored in the bones. Calcium is the most common mineral in the body and one of the most important. The body needs it to build and fix bones and teeth, help nerves work, make muscles squeeze together, help blood clot, and help the heart to...

Calcium (Ca) in Urine Test
A test for calcium in urine is a 24-hour test that checks the amount of calcium that is passed from the body in the urine. Calcium is the most common mineral in the body and one of the most important. The body needs it to build and fix bones and teeth, help nerves work, make muscles squeeze together, help blood clot...

Carbohydrates, Proteins, Fats, and Blood Sugar
The body uses three main nutrients to function—carbohydrate, protein, and fat. Carbohydrate is the nutrient that most affects your blood sugar. Protein and fat do not raise blood sugar as much as carbohydrate does. Planning meals and snacks with a...

Catecholamines in Blood Test
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...

Catecholamines in Urine Test
Catecholamines (say "kat-uh-KOH-luh-meens") are hormones made mostly by your adrenal glands as a reaction to stress. When you feel stressed, these hormones increase heart rate, blood pressure, breathing rate, muscle strength, and mental alertness. They also lower the amount of blood that goes to the skin and intestines...

Childhood Adrenocortical Carcinoma Treatment (PDQ®): Treatment - Patient Information [NCI]
Adrenocortical carcinoma is a rare disease in which malignant (cancer) cells form in the outer layer of the adrenal gland. There are two adrenal glands. The adrenal glands are small and shaped like a triangle. One adrenal gland sits on top of each kidney. Each adrenal gland has two parts. The outer layer of the adrenal...

Childhood Multiple Endocrine Neoplasia (MEN) Syndromes Treatment (PDQ®): Treatment - Patient Information [NCI]
Multiple endocrine neoplasia (MEN) syndromes are inherited disorders that affect the endocrine system. The endocrine system is made up of glands and cells that make hormones and release them into the blood. MEN syndromes may cause hyperplasia (the growth of too many normal cells) or tumors that may be benign (not...

Childhood Pheochromocytoma and Paraganglioma Treatment (PDQ®): Treatment - Patient Information [NCI]
Pheochromocytoma forms in the adrenal gland. Pheochromocytoma forms in the adrenal gland. There are two adrenal glands, one on top of each kidney in the back of the upper abdomen. Each adrenal gland has two parts. The outer layer of the adrenal gland is the adrenal cortex. The center of the adrenal gland is the adrenal...

Childhood Thyroid Cancer (PDQ®): Treatment - Patient Information [NCI]
Thyroid cancer in children is a rare cancer that forms in the thyroid, a butterfly-shaped gland at the base of the throat near the windpipe (also called the trachea). The thyroid gland has a right lobe and a left lobe that is connected by a thin piece of tissue called the isthmus. Although thyroid cancer can affect...

Chloride (Cl) Test
A chloride test measures the level of chloride in your blood or urine. Chloride is one of the most important electrolytes in the blood. It helps keep the amount of fluid inside and outside of your cells in balance. It also helps maintain proper blood volume, blood pressure, and pH of your body fluids. Tests for sodium...

Comprehensive Metabolic Panel
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...

Cortisol in Blood Test
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)...

Cortisol in Urine Test
A cortisol test measures the level of the hormone cortisol in a 24-hour sample of urine. The cortisol level may show problems with the adrenal glands or the pituitary gland. Cortisol is made by the adrenal glands. Cortisol levels get higher when the pituitary gland releases adrenocorticotropic hormone (ACTH). Cortisol...

Cushing's Syndrome
What is Cushing's syndrome? Cushing's syndrome is a rare problem that happens when you have too much of the hormone cortisol in your body. Cortisol is especially important in controlling blood pressure and metabolism. But it affects almost every area of your body. Normally, your body keeps the level of cortisol in...

DHEA-S Test
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...

Dawn Phenomenon
The dawn phenomenon can cause high blood sugar levels, especially in the morning before breakfast, in people who have diabetes. The dawn phenomenon is a normal rise in blood sugar as a person's body prepares to wake up. In the early morning hours, hormones (growth hormone, cortisol, and catecholamines) cause the liver...

Diabetes in Children: Giving Insulin Shots to a Child
Provides step-by-step instructions for preparing and giving insulin shots to a child. Includes preparing mixed-dose and single-dose shots. Links to images for how to prepare and give both types of shots. Explains where to give shots and how to rotate injection sites.

Diabetes in Children: Preparing a Care Plan for School
A diabetes care plan for school is a document that includes information to help the school or day care staff know how to manage your child's diabetes. The goal of a care plan is to meet your child's daily needs and prepare ahead of time for any problems. For example, if your child needs to eat shortly after taking...

Diabetes in Children: Preventing High Blood Sugar
Discusses high blood sugar (also called hyperglycemia) in children with diabetes. Covers symptoms. Offers tips on preventing high blood sugar emergencies.

Diabetes in Children: Treating Low Blood Sugar
If your child takes insulin or certain diabetes pills that lower blood sugar, their blood sugar may get too low at times. Low blood sugar may happen if your child: Takes too much insulin or other diabetes medicine. Skips or delays a meal or snack. Is more physically active than usual without eating enough food. Takes a...

Diabetes-Related High and Low Blood Sugar Levels
Briefly discusses high and low blood sugar levels caused by diabetes. Suggests when to check blood sugar levels. Includes info on diabetes emergencies. Offers interactive tool to help decide when to seek care. Also offers home treatment tips.

Diabetic Ketoacidosis (DKA)
Discusses diabetic ketoacidosis. Covers causes and symptoms. Discusses how it is diagnosed and treatment options.

Endometriosis: Should I Have a Hysterectomy and Oophorectomy?
Guides you through decision to have hysterectomy and oophorectomy to treat endometriosis. Covers risks of treating and not treating. Covers how well hysterectomy and removal of ovaries works. Includes interactive tool to help you make your decision.

Estrogen Test
An estrogen test measures the level of the most important estrogen hormones in a blood or urine sample. It measures estradiol, estriol, and estrone. Estradiol is the most common type of estrogen measured for nonpregnant women. The amount of estradiol in a woman's blood varies throughout her menstrual cycle. After...

Growth Hormone Test
A growth hormone (GH) test measures the amount of human growth hormone (GH) in the blood. GH is made by the pituitary gland and is needed for growth. It plays an important role in how the body uses food for energy ( metabolism). The amount of GH in the blood changes during the day and is affected by exercise, sleep...

Gynecomastia
What is gynecomastia? Gynecomastia is the overdevelopment of the male breast. A breast has both glandular tissue and fatty tissue. With gynecomastia, the glands in the breast become enlarged. The enlarged glands may feel like a rubbery disk beneath the nipple area. Both breasts are often affected. What causes it...

Home Blood Sugar Test
Discusses test to measure blood sugar (glucose) levels in those who have diabetes. Covers why and how it is done. Looks at what might affect the test. Covers risks.

Hormone Inhibin A Test
The inhibin A test is done to measure the amount of this hormone in a pregnant woman's blood to see if the baby may have Down syndrome. Inhibin A is made by the placenta during pregnancy. The level of inhibin A in the blood is used in a maternal serum quadruple screening test. Generally done between 15 and 22 weeks...

Hormone Treatment for Breast Cancer
Some breast cancers need the hormones estrogen or progesterone to grow. These cancer cells have "receptors" on their surface that let hormones in. One type is called estrogen-receptor-positive (ER+) breast cancer. Another type is called progesterone-receptor-positive (PR+) breast cancer. Hormone treatment may be used to...

Hormones
Has info on hypothyroidism, hyperthyroidism, and thyroid tests. Also has links to info on PMS and polycystic ovary syndrome.

Human Chorionic Gonadotropin (HCG) Test
The human chorionic gonadotropin (hCG) test is done to check for the hormone hCG in blood or urine. Some hCG tests measure the exact amount. Some just check to see if the hormone is present. HCG is made by the placenta during pregnancy. The test can be used to see if a woman is pregnant. HCG can be found in the blood...

Hyperparathyroidism
What is hyperparathyroidism? Hyperparathyroidism means that one or more of your four parathyroid glands may be too active. These are tiny glands in the neck, behind the thyroid gland. When they're too active, they make too much parathyroid hormone (PTH). This hormone helps control how much calcium is in your blood. When...

Hyperthyroidism
Discusses hyperthyroidism and what happens to the body's metabolism if the thyroid gland is overactive. Explains how Graves' disease usually causes an overactive thyroid. Describes symptoms. Covers exams and tests to diagnose it. Provides info on treatment.

Hyperthyroidism: Graves' Ophthalmopathy
What is Graves' ophthalmopathy? Graves' ophthalmopathy, also called thyroid eye disease, is an autoimmune disease that can occur in people with Graves' disease. In Graves' ophthalmopathy, the tissues and muscles behind the eyes become swollen. The eyeballs may stick out farther than normal. This can occur before, after...

Hypoglycemia (Low Blood Sugar) in People Without Diabetes
Discusses hypoglycemia (low blood sugar) in people who don't have diabetes. Explains blood sugar (glucose) in the body. Describes symptoms of mild, moderate, and severe hypoglycemia. Covers treatment for sudden episodes and emergency situations.

Hypothyroidism
Covers hypothyroidism, which happens when the thyroid doesn't make enough thyroxine (T4) and triiodothyronine (T3) hormones. Includes causes like thyroiditis. Covers tests for TSH, T4, and T3. Also includes info on treatment with medicine such as levothyroxine.

Hysterectomy: Should I Also Have My Ovaries Removed?
Guides you through the decision to have your ovaries removed when you have a hysterectomy. Explains why it is done. Lists the risks and benefits of having your ovaries removed. Includes interactive tool to help you make your decision.

Infertility: Questions to Ask About Medicine or Hormone Treatment
When thinking about medicine or hormone treatment for infertility, ask your doctor these questions. Are there are any long-term risks related to the treatment? Do I need to change my sexual activities during treatment? Your doctor may have suggestions for timing sex to increase the chance of getting pregnant. How long...

Ketone Test
A ketone test checks for ketones in your blood or urine. Ketones are substances that are made when the body breaks down fat for energy. Normally, your body gets the energy it needs from carbohydrate in your diet. But stored fat is broken down and ketones are made if your diet does not contain enough carbohydrates to...

Klinefelter Syndrome
Klinefelter syndrome is a genetic condition that affects males. Klinefelter syndrome occurs when someone is born with one or more extra X chromosomes. Most males have one Y and one X chromosome. Having extra X chromosomes can cause someone to have a...

Laparoscopic Ovarian Drilling (Ovarian Diathermy) for PCOS
Laparoscopic ovarian drilling is a surgical treatment for polycystic ovary syndrome (PCOS) that can help with ovulation. Electrocautery or a laser is used to destroy parts of the ovaries. This surgery is not commonly used. But it can be an option if you still don't ovulate after you lose weight and try fertility...

Levothyroxine
Make sure you know about each of the medicines you take. This includes why you take it, how to take it, what you can expect while you're taking it, and any warnings about the medicine. The information provided here is general. So be sure to read the information that came with your medicine. If you have any questions or...

Living With More Than One Health Problem
Many people have more than one long-term (chronic) health problem. You may be one of them. For example, you may have high blood pressure and diabetes, or you may have high blood pressure, diabetes, and heart failure. When you have more than one problem, doctors call the health problems comorbidities. One health problem...

Low Testosterone
What is low testosterone? Men who have low testosterone do not make enough of the male hormone called testosterone. This hormone allows men to develop and keep physical male traits. It's also one of the hormones needed for sperm production. Low testosterone is also called testosterone deficiency or hypogonadism. Low...

Luteinizing Hormone (LH) Test
A luteinizing hormone test measures the amount of luteinizing hormone (LH) in a sample of blood or urine. LH is produced by the pituitary gland. LH helps regulate the menstrual cycle and egg production ( ovulation). LH levels normally change with the phase of the menstrual cycle. This hormone goes up fast just before...

Melatonin
Melatonin is a hormone made by the pineal gland, a small gland in the brain. Melatonin helps control your sleep and wake cycles. Very small amounts of it are found in foods such as meats, grains, fruits, and vegetables. You can also buy it as a supplement.

Menopause: Managing Hot Flashes
Discusses options for managing hot flashes during menopause. Explains what hot flashes are. Discusses lifestyle choices that may help hot flashes. Looks at prescription medicines.

Menopause: Should I Use Hormone Therapy (HT)?
Guides you through the decision to use hormone therapy (HT) for menopause symptoms. Explains what menopause is and what to expect. Lists risks and benefits of HT and other treatments to try. Includes interactive tool to help you decide.

Menstrual Diary to Monitor Premenstrual Symptoms
A menstrual diary is a helpful tool for better understanding your premenstrual symptoms and then deciding how to treat them. Regardless of whether you have full-blown, diagnosable premenstrual syndrome (PMS), your menstrual diary can help you plan ahead for, prevent, and better cope with your premenstrual symptoms. You...

Metabolic Syndrome
Discusses metabolic syndrome, a group of health problems. These problems increase the risk for diabetes and heart disease (coronary artery disease). Covers risk factors like obesity, high blood pressure, and high cholesterol. Covers diet and exercise to improve health.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome
What is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)? Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disease that causes you to feel so ill that you can't do your normal activities. Sleeping problems occur along with extreme fatigue that doesn't get better with rest. Any kind of activity...

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Managing Your Energy
Two techniques can help you manage your energy when you have ME/CFS. They are: Staying within your energy envelope. Pacing yourself. These techniques can give you better control over your symptoms so that you can be as active as possible. They may also lead to fewer times when you feel so ill that you can't do anything...

Night Sweats
What are night sweats? Night sweats are heavy sweating during sleep. This kind of sweating is different than the occasional sweating people have from sleeping deeply, being in a warm room, or having too many blankets. Night sweats are often so heavy that your clothing and sheets are soaked to the point that you have to...

Oral Glucose Tolerance Test (OGTT)
Discusses oral glucose tolerance test that measures glucose (blood sugar) levels. Explains that test checks for gestational diabetes, prediabetes, and diabetes. Covers the types of tests done and how to prepare for them.

Overnight Dexamethasone Suppression Test
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...

Oxytocin
Explains how oxytocin creates the let-down reflex and shrinks the uterus.

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

Pancreatic Cancer Treatment (PDQ®): Treatment - Patient Information [NCI]
Pancreatic cancer is a type of cancer that forms in the tissues of the pancreas. The pancreas is a gland about 6 inches long that is shaped like a thin pear lying on its side. The wider end of the pancreas is called the head, the middle section is called the body, and the narrow end is called the tail. The pancreas lies...

Pancreatic Neuroendocrine Tumors (Islet Cell Tumors) Treatment (PDQ®): Treatment - Patient Information [NCI]
Pancreatic neuroendocrine tumors form in hormone-making cells (islet cells) of the pancreas. The pancreas is a gland about 6 inches long that is shaped like a thin pear lying on its side. The wider end of the pancreas is called the head, the middle section is called the body, and the narrow end is called the tail. The...

Parathyroid Cancer Treatment (PDQ®): Treatment - Patient Information [NCI]
Parathyroid cancer is a rare disease in which malignant (cancer) cells form in the tissues of a parathyroid gland. The parathyroid glands are four pea-sized organs found in the neck near the thyroid gland. The parathyroid glands make parathyroid hormone (PTH or parathormone). PTH helps the body use and store calcium to...

Parathyroid Hormone (PTH) Test
Covers why and how parathyroid hormone tests are done. Covers what possible results might mean. Includes info on what might affect the test.

Pheochromocytoma and Paraganglioma Treatment (PDQ®): Treatment - Patient Information [NCI]
Pheochromocytoma and paraganglioma are rare tumors that come from the same type of tissue. Paragangliomas form in nerve tissue in the adrenal glands and near certain blood vessels and nerves. Paragangliomas that form in the adrenal glands are called pheochromocytomas. Paragangliomas that form outside the adrenal glands...

Pituitary Tumors Treatment (PDQ®): Treatment - Patient Information [NCI]
A pituitary tumor is a growth of abnormal cells in the tissues of the pituitary gland. Pituitary tumors form in the pituitary gland, a pea-sized organ in the center of the brain, just above the back of the nose. The pituitary gland is sometimes called the "master endocrine gland" because it makes hormones that...

Polycystic Ovary Syndrome (PCOS)
Discusses polycystic ovary syndrome, a problem in which female hormones are out of balance. Discusses PCOS early symptoms like heavy bleeding or facial hair. Also covers more serious symptoms like miscarriages or infertility. Includes info on treatment.

Potassium (K) in Blood Test
Discusses blood test to check level of potassium (K) in blood. Includes info on what affects potassium levels in the body such as kidney function, blood pH, and hormones. Explains how and why test is done. Covers what results mean.

Prediabetes
Covers warning signs that you may be at risk for type 2 diabetes. Includes causes and symptoms. Looks at lifestyle changes to get your blood sugar levels back to a normal range. Includes tips on diet, weight loss, and exercise.

Premenstrual Syndrome (PMS)
Covers symptoms of PMS such as bloating, muscle aches, and mood swings. Discusses possible causes and what increases your risk. Covers treatment with lifestyle changes, antidepressants, or birth control pills. Covers surgery for severe form (PMDD).

Progesterone Test
A progesterone test measures the amount of the hormone progesterone in a blood sample. Progesterone is a hormone produced by the ovaries during release of a mature egg from an ovary (ovulation). Progesterone helps prepare the lining of the uterus (endometrium) to receive the egg if it becomes fertilized by a sperm. If...

Prolactin Blood Test
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...

Radioactive Iodine Treatment
Radioactive iodine, given in a capsule or liquid form, is absorbed and concentrated by the thyroid gland. The treatment destroys thyroid tissue but does not harm other tissue in the body. While radiation can cause thyroid cancer, treatment of hyperthyroidism with radioactive iodine does not increase your chances of...

Radioactive Iodine Treatment for Hyperthyroidism
Radioactive iodine is a medicine that you take one time. After you swallow it, it is taken up by your thyroid gland. Depending on the dosage used, the radioactivity in the iodine destroys most or all of the tissue in your thyroid gland, but it does not harm any other parts of your body. While radiation can cause thyroid...

Radioactive Iodine Uptake Test
A radioactive iodine uptake (RAIU) test uses a radioactive tracer and a special probe to measure how much tracer the thyroid gland absorbs from the blood. The test can show how much tracer is absorbed by the thyroid gland. The RAIU test often is done along with a thyroid scan, which shows if the tracer is evenly spread...

Renin Blood Test
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...

Secondary Adrenocortical Insufficiency
What is secondary adrenocortical insufficiency? Secondary adrenocortical insufficiency is a condition in which a lack of adrenocorticotropic hormone (ACTH) prevents the body from producing enough cortisol. Production of cortisol is controlled by the action of ACTH. ACTH is produced by the pituitary gland. This gland is...

Sick-Day Guidelines for People With Diabetes
What happens when you are sick If you have diabetes, other illnesses can make your blood sugar go up. This can be dangerous. When you're sick with the flu or another illness, your body releases hormones to fight infection. These hormones raise blood sugar levels. They also make it hard for insulin or other medicines to...

Storing Insulin and Prefilling Syringes
Insulin can become damaged and ineffective if it is not stored properly. Unopened insulin that is packaged in small glass bottles (vials) should be stored in the refrigerator. Liquid insulin that is packaged in small cartridges (containing several...

Subclinical Hyperthyroidism
You may have a very mild form of hyperthyroidism called subclinical hyperthyroidism if your thyroid tests show that: Your thyroid-stimulating hormone (TSH) levels are low. Your thyroid hormones thyroxine (T4) and triiodothyronine (T3) are normal. Subclinical hyperthyroidism is different from hyperthyroidism. Your TSH...

Subclinical Hypothyroidism
A doctor diagnoses mild, or subclinical, hypothyroidism through a medical history and physical exam. If your doctor suspects that you have subclinical hypothyroidism, you will have lab tests to confirm the diagnosis. Subclinical hypothyroidism is diagnosed when you have: No symptoms or mild symptoms of hypothyroidism...

Symptoms of High Blood Sugar
High blood sugar (hyperglycemia) most often occurs in people who have diabetes that isn't well controlled. The symptoms of high blood sugar can be mild, moderate, or severe. Young children are not able to recognize symptoms of high blood sugar. Parents need to do a home blood sugar test on their child whenever they...

Testosterone
Make sure you know about each of the medicines you take. This includes why you take it, how to take it, what you can expect while you're taking it, and any warnings about the medicine. The information provided here is general. So be sure to read the information that came with your medicine. If you have any questions or...

Testosterone Test
A testosterone test checks the level of this male hormone (androgen) in the blood. Testosterone affects sexual features and development. In men, it is made in large amounts by the testicles. In both men and women, testosterone is made in small amounts by the adrenal glands, and in women, by the ovaries. The pituitary...

Thyroid Biopsy
A thyroid biopsy is a procedure in which a small sample of tissue is removed from the thyroid gland and looked at under a microscope for cancer, infection, or other thyroid problems. The thyroid gland is found in front of the windpipe (trachea), just below the voice box (larynx). A sample of thyroid tissue can be taken...

Thyroid Cancer
Discusses causes and symptoms of thyroid cancer. Covers factors that increase risk, including exposure to radiation. Discusses diagnosis and treatment with surgery, radioactive iodine, and thyroid hormone therapy.

Thyroid Cancer Screening (PDQ®): Screening - Patient Information [NCI]
Screening is looking for cancer before a person has any symptoms. This can help find cancer at an early stage. When abnormal tissue or cancer is found early, it may be easier to treat. By the time symptoms appear, cancer may have begun to spread. Scientists are trying to better understand which people are more likely to...

Thyroid Cancer Treatment (PDQ®): Treatment - Patient Information [NCI]
Thyroid cancer is a disease in which malignant (cancer) cells form in the tissues of the thyroid gland. The thyroid is a gland at the base of the throat near the trachea (windpipe). It is shaped like a butterfly, with a right lobe and a left lobe. The isthmus, a thin piece of tissue, connects the two lobes. A healthy...

Thyroid Hormone Production and Function
The thyroid gland uses iodine from food to make two thyroid hormones: triiodothyronine (T3) and thyroxine (T4). It also stores these thyroid hormones and releases them as they are needed. The hypothalamus and the pituitary gland, which are located in the brain, help control the thyroid gland. The hypothalamus releases...

Thyroid Hormone Replacement for Hypothyroidism
Thyroid hormones help regulate the way the body uses energy. You need thyroid hormone replacement when you do not have enough thyroid hormones in your blood (hypothyroidism). Depending on the cause of your hypothyroidism, you may need to take thyroid hormones for the rest of your life. Thyroid hormones are usually taken...

Thyroid Hormone Tests
Looks at various tests used to check how well the thyroid gland is working. Covers what results might mean. Also looks at what might affect a test. Offers links to info on other tests that might be useful, including thyroid-stimulating hormone (TSH) test.

Thyroid Hormones
Thyroid hormones affect every cell and all the organs of the body. Too much thyroid hormone speeds things up and too little thyroid hormone slows things down. They: Control the rate at which your body burns calories (your metabolism). This affects whether you gain or lose weight. Can slow down or speed up your...

Thyroid Nodules
What are thyroid nodules? Thyroid nodules are growths or lumps in the thyroid gland. This gland controls how your body uses energy. Most thyroid nodules are not cancer and do not cause problems. Many don't even need treatment. A thyroid nodule may cause problems, such as making too much thyroid hormone. When this...

Thyroid Scan
A thyroid scan uses a radioactive tracer and a special camera to measure how much tracer the thyroid gland absorbs from the blood. The tracer can be swallowed or can be injected into a vein. It travels through your body, giving off radiation signals. The camera "sees" the signals and can measure how much tracer the...

Thyroid Screening Recommendations
Experts do not agree on whether adults who don't have symptoms of thyroid problems should have a thyroid test. The American Thyroid Association and the American Association of Clinical Endocrinologists recommend that testing be considered for those older than age 60. The U.S. Preventive Services Task Force makes no...

Thyroid Storm
Thyroid storm (thyroid crisis) is a potentially life-threatening condition for people who have hyperthyroidism. Thyroid storm happens when your thyroid gland suddenly releases large amounts of thyroid hormone in a short period of time. If you have thyroid storm, you will need emergency medical treatment. Thyroid storm...

Thyroid Surgery
Thyroid surgery takes out part or all of your thyroid gland. The gland makes hormones that control how your body makes and uses energy (metabolism). A doctor may take out part or all of the gland when it gets too big, doesn't work right, or has a growth. Most growths or lumps in this gland are benign. This means they...

Thyroid and Parathyroid Ultrasound
Covers imaging test to check the thyroid gland and parathyroid glands. Includes info on problems the test checks for, such as lumps in the thyroid gland or enlarged thyroid and parathyroid glands. Covers how it's done. Discusses possible results.

Thyroid-Stimulating Hormone (TSH) Test
Discusses blood test used to check for thyroid gland problems. Explains how TSH causes thyroid gland to make hormones that help control metabolism. Covers how it is done and test results.

Treating Diabetic Foot Problems
Foot problems from diabetes are treated by keeping blood sugar levels in your target range. Other types of treatment include medicine, special shoes, and surgery. Treatment for foot ulcers includes keeping weight off your injured foot. A cast or special boot, shoe inserts, crutches, a wheelchair, or bed rest may be...

Type 1 Diabetes
Covers type 1 diabetes, also called juvenile diabetes or insulin-dependent diabetes. Describes how pancreas regulates blood sugar (glucose) levels. Includes info on hypoglycemia and hyperglycemia. Discusses treatments, including insulin.

Type 1 Diabetes in Children
Covers type 1 diabetes in children. Includes info on managing diabetes. Discusses using glucose monitors for blood glucose testing. Includes links to info on dealing with diabetes in school. Includes info on hypoglycemia and hyperglycemia.

Type 2 Diabetes
Information on type 2 diabetes. Describes how insulin is made and used by the body. Describes symptoms and how type 2 is treated. Provides info on blood sugar (glucose) levels. Discusses obesity's role in type 2 diabetes. Discusses exercise and diet.

Type 2 Diabetes: Screening for Adults
Doctors follow guidelines from experts to decide when to test adults for type 2 diabetes. Talk with your doctor about your risk for type 2 diabetes and how often you need to be tested. The U.S. Preventive Services Task Force recommends testing for prediabetes and type 2 diabetes in people who are overweight or obese and...

Types of Insulin
Insulin is used to treat people who have diabetes. How quickly insulin starts to work and how long it lasts will be different depending on the type of insulin you use. Other factors that can affect insulin and your blood sugar are exercise, diet,...

Types of Thyroid Cancer
There are different types of thyroid cancer. They are based on what the cells look like under a microscope. Your treatment will depend on which type of thyroid cancer you have. These include: Papillary thyroid cancer. This is the most common type of thyroid cancer. It's often only found in one lobe of the thyroid...

Unwanted Hair in Women
What is unwanted hair in women? Hirsutism (say "HER-suh-tiz-um") is extra hair on a woman's face or body. This hair is dark and coarse. It grows in a male pattern: on the face, like a man's facial hair, or on the body, especially the chest and back. What causes it? Usually extra hair growth (hirsutism) is not a medical...

Whipple Surgery for Pancreatic Cancer
Looks at a type of surgery that removes cancer from the pancreas. Covers why surgery is done and how well it works. Also covers risks.