Endocrinologists must first complete seven or more years of medical school and postgraduate training and become board certified in Internal Medicine. Then, for an additional two to three years, they study conditions specific to the endocrine system -- tissues and major endocrine glands, including the pituitary, pineal, thyroid, parathyroids, thymus, adrenals, pancreas, ovaries, and testes.

Many other organs also secrete hormones -- the kidney, heart, stomach, hypothalamus, brain, and placenta. These glands and tissues secrete hormones, bodily chemicals that affect every known physiological function. Hormones travel in your blood throughout the body and affect many organs, including your brain, heart, liver, kidneys, bone, skin and all endocrine glands.

Hormones initiate and regulate reproduction, growth and development, and responses to stress and the environment. These natural chemicals also increase the body's efficiency and regulate activity levels, metabolism, appetite, thirst, digestion, blood circulation, salt and water balance and the excretion of metabolic waste. 

Endocrinologists provide treatment for a wide range of functions and disorders of the human body -- diabetes, thyroid disorders, infertility, metabolism, glandular cancers, growth hormone deficiency, genetic dysfunction, heart disease, osteoporosis, obesity and hormonal imbalances. Endocrinologists also conduct clinical research.

Not everyone who suffers from endocrine disease needs an endocrinologist.  A general internist can diagnose and treat uncomplicated hormonal disorders, such as well-controlled diabetes, high blood pressure, and follow-up treatment for hyperthyroidism.

The skills of an endocrinologist are necessary for complicated disorders, such as uncontrolled diabetes, thyroid cancer, pituitary dysfunction, familial endocrine and auto-immune disease. In most cases, you will still need an internist or other primary care physician for non-endocrinology related medical care, although some endocrinologists maintain a general internal medicine practice as well as their subspecialty. 

If you have been referred by your primary care physician to an endocrinologist, in most cases you will go back to that physician for follow-up care. If you require continuing care for endocrinology-related conditions, your primary care physician and your endocrinologist, working together, will recommend which physician you should see. If you have questions about which physician to see, be sure to ask.

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