Failure of the Pituitary Gland (Hypopituitarism) is a very rare condition. The pituitary gland controls all the other hormone-producing glands in the body. Symptoms can be fatigue, decreased energy, and other symptoms of hypothyroidism. Women may get early menopause. Men may have sexual problems, and gain weight. Children with hypopituitarism don’t make growth hormone, so they fail to grow.
Diagnosis is usually made by blood test looking for hypothyroidism as a cause of fatigue or menstrual problems (it’s much more common than hypopituitarism). We find a low TSH which suggests hyperthyroidism, but the Free T4 test then surprisingly winds up low also (see Thyroid Physiology for explanation of how thyroid labs work). That makes us order other pituitary hormones like growth hormone (GH), follicle stimulating hormone (FSH), luteinizing hormone (LH), and ACTH, many or all of which will wind up low.
If we find Hypopituitarism, we order a pituitary MRI to make look for a tumor (if so, it’s not usually cancer). Other causes of pituitary insufficiency include brain trauma or surgery, stroke, & sudden loss of blood supply due to hemorrhage right after pregnancy delivery. Treatment involves replacing whatever hormones are lacking; sometimes a tumor requires surgery.