Health Topics

Endocrine system

Endocrine Diseases
National Library of Medicine
Multiple Endocrine Neoplasia

Your endocrine system includes eight major glands throughout your body. These glands make hormones. Hormones are chemical messengers. They travel through your bloodstream to tissues or organs. Hormones work slowly and affect body processes from head to toe. These include

  • Growth and development
  • Metabolism - digestion, elimination, breathing, blood circulation and maintaining body temperature
  • Sexual function
  • Reproduction
  • Mood

If your hormone levels are too high or too low, you may have a hormone disorder. Hormone diseases also occur if your body does not respond to hormones the way it is supposed to. Stress, infection and changes in your blood's fluid and electrolyte balance can also influence hormone levels.

In the United States, the most common endocrine disease is diabetes. There are many others. They are usually treated by controlling how much hormone your body makes. Hormone supplements can help if the problem is too little of a hormone.


Endocrine System Diseases
Endocrine System
Your endocrine system includes eight major glands throughout your body. These glands make hormones. Hormones are chemical messengers. They travel through ...
Hormones
National Library of Medicine

Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work slowly, over time, and affect many different processes, including

  • Growth and development
  • Metabolism - how your body gets energy from the foods you eat
  • Sexual function
  • Reproduction
  • Mood

Endocrine glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, thymus, thyroid, adrenal glands, and pancreas. In addition, men produce hormones in their testes and women produce them in their ovaries.

Hormones are powerful. It takes only a tiny amount to cause big changes in cells or even your whole body. That is why too much or too little of a certain hormone can be serious. Laboratory tests can measure the hormone levels in your blood, urine, or saliva. Your health care provider may perform these tests if you have symptoms of a hormone disorder. Home pregnancy tests are similar - they test for pregnancy hormones in your urine.


Hormones
Endocrine System
Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work slowly, over time, and affect many different processes, ...
Pituitary Disorders
National Library of Medicine
Acromegaly

Your pituitary gland is a pea-sized gland at the base of your brain. The pituitary is the "master control gland" - it makes hormones that affect growth and the functions of other glands in the body.

With pituitary disorders, you often have too much or too little of one of your hormones. Injuries can cause pituitary disorders, but the most common cause is a pituitary tumor.


Pituitary Diseases
Brain and Nerves
Endocrine System
Your pituitary gland is a pea-sized gland at the base of your brain. The pituitary is the "master control gland" - it makes hormones that affect growth and the ...
Adrenal Gland Disorders
National Library of Medicine
Congenital Adrenal Hyperplasia

The adrenal glands are small glands located on top of each kidney. They produce hormones that you can't live without, including sex hormones and cortisol. Cortisol helps you respond to stress and has many other important functions.

With adrenal gland disorders, your glands make too much or not enough hormones. In Cushing's syndrome, there's too much cortisol, while with Addison's disease, there is too little. Some people are born unable to make enough cortisol.

Causes of adrenal gland disorders include

  • Genetic mutations
  • Tumors including pheochromocytomas
  • Infections
  • A problem in another gland, such as the pituitary, which helps to regulate the adrenal gland
  • Certain medicines

Treatment depends on which problem you have. Surgery or medicines can treat many adrenal gland disorders.

NIH: National Institute of Child Health and Human Development


Adrenal Gland Diseases
Endocrine System
The adrenal glands are small glands located on top of each kidney. They produce hormones that you can't live without, including sex hormones and cortisol. ...
Anatomy
National Library of Medicine

Anatomy is the science that studies the structure of the body. On this page, you'll find links to descriptions and pictures of the human body's parts and organ systems from head to toe.


Anatomy
Digestive System
Blood, Heart and Circulation
Eyes and Vision
Bones, Joints and Muscles
Kidneys and Urinary System
Brain and Nerves
Lungs and Breathing
Ear, Nose and Throat
Mouth and Teeth
Skin, Hair and Nails
Pregnancy and Reproduction
Immune System
Endocrine System
Male Reproductive System
Anatomy is the science that studies the structure of the body. On this page, you'll find links to descriptions and pictures of the human body's parts and organ ...
Thymus Cancer
National Library of Medicine
Thymoma

The thymus is a small organ in your upper chest, under your breastbone. Before birth and during childhood, the thymus helps the body make a type of white blood cell. These cells help protect you from infections.

Cancer of the thymus is rare. You are more likely to get it if you have other diseases such as myasthenia gravis, lupus or rheumatoid arthritis. Sometimes there are no symptoms. Other times, thymus cancer can cause

  • A cough that doesn't go away
  • Chest pain
  • Trouble breathing

Doctors use a physical exam, imaging tests, and a biopsy to diagnose thymus cancer. The most common treatment is surgery to remove the tumor. Other options include radiation therapy, chemotherapy, and hormone therapy.

NIH: National Cancer Institute


Thymus Neoplasms
Cancers
Immune System
Endocrine System
The thymus is a small organ in your upper chest, under your breastbone. Before birth and during childhood, the thymus helps the body make a type of white ...
Parathyroid Disorders
National Library of Medicine
Hyperparathyroidism
Hypoparathyroidism
Multiple Endocrine Neoplasia

Most people have four pea-sized glands, called parathyroid glands, on the thyroid gland in the neck. Though their names are similar, the thyroid and parathyroid glands are completely different. The parathyroid glands make parathyroid hormone (PTH), which helps your body keep the right balance of calcium and phosphorous.

If your parathyroid glands make too much or too little hormone, it disrupts this balance. If they secrete extra PTH, you have hyperparathyroidism, and your blood calcium rises. In many cases, a benign tumor on a parathyroid gland makes it overactive. Or, the extra hormones can come from enlarged parathyroid glands. Very rarely, the cause is cancer.

If you do not have enough PTH, you have hypoparathyroidism. Your blood will have too little calcium and too much phosphorous. Causes include injury to the glands, endocrine disorders, or genetic conditions. Treatment is aimed at restoring the balance of calcium and phosphorous.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


Parathyroid Diseases
Endocrine System
Most people have four pea-sized glands, called parathyroid glands, on the thyroid gland in the neck. Though their names are similar, the thyroid and parathyroid ...
Cushing's Syndrome
National Library of Medicine
Hypercortisolism

Cushing's syndrome is a hormonal disorder. The cause is long-term exposure to too much cortisol, a hormone that your adrenal gland makes. Sometimes, taking synthetic hormone medicine to treat an inflammatory disease leads to Cushing's. Some kinds of tumors produce a hormone that can cause your body to make too much cortisol.

Cushing's syndrome is rare. Some symptoms are

  • Upper body obesity
  • Thin arms and legs
  • Severe fatigue and muscle weakness
  • High blood pressure
  • High blood sugar
  • Easy bruising

Lab tests can show if you have it and find the cause. Your treatment will depend on why you have too much cortisol. If it is because you have been taking synthetic hormones, a lower dose may control your symptoms. If the cause is a tumor, surgery and other therapies may be needed.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


Cushing Syndrome
Endocrine System
Cushing's syndrome is a hormonal disorder. The cause is long-term exposure to too much cortisol, a hormone that your adrenal gland makes. Sometimes, taking synthetic ...
Thyroid Diseases
National Library of Medicine
Goiter

Your thyroid is a butterfly-shaped gland in your neck, just above your collarbone. It is one of your endocrine glands, which make hormones. Thyroid hormones control the rate of many activities in your body. These include how fast you burn calories and how fast your heart beats. All of these activities are your body's metabolism.

Thyroid problems include

  • Goiter - enlargement of the thyroid gland
  • Hyperthyroidism - when your thyroid gland makes more thyroid hormones than your body needs
  • Hypothyroidism - when your thyroid gland does not make enough thyroid hormones
  • Thyroid cancer
  • Thyroid nodules - lumps in the thyroid gland
  • Thyroiditis - swelling of the thyroid

To diagnose thyroid diseases, doctors use a medical history, physical exam, and thyroid tests. They sometimes also use a biopsy. Treatment depends on the problem, but may include medicines, radioiodine therapy, or thyroid surgery.

Dept. of Health and Human Services Office on Women's Health


Thyroid Diseases
Endocrine System
Your thyroid is a butterfly-shaped gland in your neck, just above your collarbone. It is one of your endocrine glands, which make hormones. Thyroid hormones ...
Addison Disease
National Library of Medicine
Adrenal Insufficiency
Adrenocortical hypofunction
Hypocortisolism

Your adrenal glands are just above your kidneys. The outside layer of these glands makes hormones that help your body respond to stress and regulate your blood pressure and water and salt balance. Addison disease happens if the adrenal glands don't make enough of these hormones.

A problem with your immune system usually causes Addison disease. The immune system mistakenly attacks your own tissues, damaging your adrenal glands. Other causes include infections and cancer.

Symptoms include

  • Weight loss
  • Muscle weakness
  • Fatigue that gets worse over time
  • Low blood pressure
  • Patchy or dark skin

Lab tests can confirm that you have Addison disease. If you don't treat it, it can be fatal. You will need to take hormone pills for the rest of your life. If you have Addison disease, you should carry an emergency ID. It should say that you have the disease, list your medicines and say how much you need in an emergency.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


Addison Disease
Immune System
Endocrine System
Your adrenal glands are just above your kidneys. The outside layer of these glands makes hormones that help your body respond to stress and regulate your ...