Traumatic Brain Injury:  Effects on the Endocrine System

Fact Sheet

Traumatic Brain Injury

  • Editors
  • Jens Bollerslev, MD
    Anne Klibanski, MD
    Nicholas Tritos, MD

What is traumatic brain injury?

Traumatic brain injury, also called TBI, is sudden damage to the brain. It happens when the head hits something violently or is hit again and again, or when an object goes through the skull and into the brain. Causes include

Hypothalamuspituitary glandWhat is the endocrine system?

Your endocrine system includes glands and organs that make and release hormones, which are chemicals that help your body work properly. They control growth, sexual development, how your body uses and stores energy (metabolism), how it deals with illness, and more. You need proper types and amounts of hormones to feel well.

How can TBI affect the endocrine system?

Two important parts of the endocrine system—the pituitary gland and the hypothalamus—are located in or near the brain. TBI can injure them, causing hormone problems. A person with TBI may have hormone problems right away or months or even years after the injury.

Did you know?

The hypothalamus and the pituitary gland are like orchestra conductors.  Their job is to tell other endocrine glands throughout the body to make the hormones that affect and protect every aspect of your health.

What hormone problems can happen with TBI?

Someone with TBI can have one or more problems, depending on the injury. Problems that often occur soon after TBI include

Problems that may occur later and their symptoms include


  • Hypothalamus: a part of the brain that controls the release of hormones made by the pituitary gland
  • Pituitary gland: located at the base of the brain, it’s called the “master gland” because it makes hormones that tell other glands (such as the thyroid or adrenal glands) to make other kinds of hormones
  • Thyroid gland:  found in the neck, it makes thyroid hormones, which control metabolism; helps the heart, muscles, and other organs work properly
  • Adrenal glands: one located on top of each kidney, they make cortisol, which helps the body cope with stress, illness, and injury

How are TBI-related hormone problems diagnosed?

Your doctor will ask about your medical history and do a physical exam. Blood tests are done to check your hormone levels. You may have an MRI to look at the pituitary gland and check for tumors, cysts, or other problems.

What is the treatment for TBI-related hormone problems?

Often, you will take hormones to replace what’s missing (called hormone therapy). Other problems require various treatments, such as treating hyponatremia by cutting back on fluid intake, getting an IV (through a vein) salt solution, and taking medicines.

What’s the long-term outlook for TBI-related hormone problems?

The outlook depends on the type of problem and how severe it is. Some endocrine problems may be temporary and disappear within a year after TBI. Hormone therapy is a very important part of treatment. It can restore your health, relieve symptoms, and improve your quality of life. In some cases, it can save your life.

Some Hormones Made by the Pituitary Gland and What They Do

Hormone Job
ACTH (adrenocorticotropin) Tells the adrenal glands to make cortisol (the “stress” hormone)
ADH (antidiuretic hormone) Helps control the amount of water in the body
FSH (follicle-stimulating hormone) and LH (luteinizing hormone) Help ovaries and testes (testicles) work properly
GH (growth hormone) In kids, helps them grow taller, increases muscle, and decrease body fat. In adults, helps metabolism. Helps keep muscle and bone healthy.
Prolactin Starts breast milk production after childbirth; can affect sex hormones
TSH (thyroid-stimulating hormone) Tells the thyroid gland to make thyroid hormones

Questions to ask your doctor