An endocrinologist is a doctor who specializes in endocrinology, a branch of medicine that studies the hormonal glands and the diseases and disorders that affect them. The specialty includes the evaluation of a wide range of symptoms associated with a deficiency or excess of hormones. Many of these conditions are chronic (that is, they persist for a long time) and require constant and even lifelong treatment.
An endocrinologist first trains in internal medicine , pediatrics , or gynecology and then specializes in endocrinology. In the United States, typical training includes four years of college, four years of medical school, three years of residency, and two years of an internship.
According to a 2014 study published in the Journal of Clinical Endocrinology and Metabolism, endocrinologists are in high demand, with fewer than 4,000 actively practicing them in the US.
Endocrinology is a specialty of internal medicine whose function is to evaluate how hormones can affect, among others, metabolism, height, weight, sleep, digestion, mood, reproductive function, sensory perception, menstruation, lactation and organ function.
Although each organ system secretes and responds to hormones, endocrinology focuses primarily on the organs of the endocrine system , in particular
- The adrenal glands , two glands above the kidneys that secrete cortisol , the body's main stress hormone, and aldosterone, which regulates blood pressure and sodium levels.
- The hypothalamus , the part of the lower middle brain that tells the pituitary gland when to release hormones.
- The ovaries , the female reproductive organs that produce female sex hormones.
- The pancreas , an organ in the abdomen that makes the hormones insulin and glucagon.
- The parathyroid gland , four glands in the neck that play a key role in bone development and the regulation of calcium in the blood.
- The pineal gland is a gland in the center of the brain that helps regulate sleep patterns.
- The pituitary gland , often called the "master gland," because it affects the function of all other glands.
- Testicles , male sex glands that produce male sex hormones.
- The thymus , an organ in the upper chest that affects the development of the immune system at a young age.
- The thyroid gland , a butterfly-shaped organ in the neck that regulates metabolism.
Any dysfunction of these organs can affect the amount or little amount of hormones that are produced. Also, since endocrine organs influence each other, organ dysfunction can have an indirect effect and lead to multiple hormonal imbalances.
Endocrine disorders can be caused by disease, injury, infection, or a benign or malignant neoplasm. There are also genetic disorders that can affect the normal function of the gland. Failures in the endocrine feedback loop (the system in which the endocrine glands respond to external stimuli or to each other) can also lead to imbalances.
Among the conditions that an endocrinologist can treat (or participate in treatment):
- Diseases of the adrenal glands , including Addison's disease and Cushing's disease.
- Thyroid cancer
- Development and growth problems in boys , including late puberty, precocious puberty, short stature, gigantism , and disorders of sexual differentiation (DSD)
- Diabetes , including type 1 diabetes, type 2 diabetes, and gestational diabetes
- Gynecological conditions such as premenstrual syndrome (PMS), amenorrhea , polycystic ovary syndrome (PCOS), endometriosis , and symptoms of menopause .
- Infertility , which is often affected by sex hormones in men and women, as well as adrenal and thyroid hormones.
- Multiple endocrine neoplasia (MEN) syndromes, rare disorders that cause the development of tumors in the endocrine glands.
- Osteoporosis is a condition commonly associated with estrogen deficiency, menopause, hyperthyroidism, and low testosterone levels.
- Paget's disease, a disease that interferes with the replacement of old bone with new bone.
- Pituitary gland tumors , often benign
- Thyroid disorders , including hyperthyroidism , hypothyroidism , Graves' disease , Hashimoto's thyroiditis, and other types of thyroiditis.
Depending on the condition, the endocrinologist may work alone or with other healthcare professionals, including gynecologists, neurologists, oncologists, osteopathic surgeons, pediatricians, and primary care physicians.
If you are referred to an endocrinologist, this is usually due to signs (laboratory findings or symptoms) of a hormonal imbalance. Endocrinologists are rarely your first point of contact for a medical condition and almost never work as therapists .
Endocrinology is unique in that the diagnosis and treatment of endocrine diseases relies more on laboratory tests than on almost any other medical specialty.
Blood and urine tests are generally used to measure hormone levels in blood or urine samples. Other tests include injecting a stimulating or inhibiting agent to see how the endocrine gland responds. In addition to blood tests, an endocrinologist may order imaging studies and other procedures to take a closer look at the gland.
Some of the tests that an endocrinologist usually prescribes include:
- 24-hour urine collection , which provides a more accurate picture of hormone levels in the body, including cortisol.
- ACTH stimulation test , which uses an injection of adrenocorticotropic hormone (ACTH) to diagnose adrenal dysfunction.
- Computed tomography (CT) , a type of computed radiography that creates three-dimensional "slices" of internal structures.
- A CRH stimulation test that uses an injection of corticotropin-releasing hormone (CRH) to detect adrenal dysfunction.
- Dexamethasone suppression test , which uses a synthetic cortisol injection to detect Cushing's disease.
- Fine needle aspiration (FNA) biopsy , in which a needle is inserted into the thyroid gland or tumor to remove cells for microscopic evaluation.
- Magnetic resonance imaging (MRI) , which uses powerful radio and magnetic waves to create highly detailed images, especially of the pituitary gland.
- Metaiodobenzylguanidine (MIBG) scan , sometimes used to detect metastatic cancer
- An oral glucose tolerance test in which you drink a sugary drink with glucose to help diagnose diabetes.
- Dotate scan, in which a radioisotope, gallium 68, enters the body and binds to somatostatin receptors, which are highly expressed in most neuroendocrine tumors.
- Positron emission tomography (PET) , an imaging test that uses a radioactive substance to detect metabolic abnormalities seen in most cancers
- A radioactive iodine scan (RAI) used to detect normal and cancer cells in the thyroid gland.
- Ultrasound , both abdominal and endoscopic, which uses sound waves to detect masses or fluid in soft tissues.
- Venous sampling , which involves inserting a catheter into a vein to draw blood from a specific part of the body for hormonal tests.
The treatments used in endocrinology are very varied depending on the diseases involved. Many disorders can be treated with hormone replacement therapy (HRT), which uses oral or injectable medications to overcome diagnosed deficiencies. From them:
- Glucocorticoid tablets can replace hormones in people with impaired adrenal or pituitary function.
- Growth hormone therapy , which includes injections of growth hormone (GH), is sometimes used to treat growth disorders in children and GH deficiency in adults.
- Hormonal contraceptives can be used to treat PMS, PMS, and endometriosis, or to prevent postmenopausal osteoporosis.
- Insulin and other diabetes medications can help normalize blood sugar levels in people with diabetes.
- Testosterone replacement , which includes injections, patches, tablets, and gel, can be used in men and women with low levels of testosterone ( hypogonadism ).
- Thyroid replacement medications , including Synthroid (levothyroxine) and Cytomel (liothyronine), can be used to restore thyroid function in people with hypothyroidism.
In other cases, surgery and other procedures may be required to correct an endocrine disorder. Examples include:
- Adrenalectomy , a surgical procedure to remove the adrenal gland for cancer or Cushing's disease.
- Gamma knife radiosurgery , a type of surgery that involves about 200 beams of radiation to precisely remove tumors, including those in the hypothalamus.
- Radioactive iodine ablation, which uses radioactive iodine to destroy residual tissue after thyroidectomy.
- Thyroidectomy is a surgical procedure to totally or partially remove the thyroid gland in cases of thyroid cancer, thyroid nodules, and hyperthyroidism.
Because endocrinology is such a vast and varied field, some endocrinologists will choose to limit their practice to specific conditions, populations, or procedures. Examples include:
- Diabetes and metabolism
- Endocrine oncology (including cancer)
- Endocrinology nuclear medicine
- Sex change
- Pediatric endocrinology
- Reproductive endocrinology (also known as reproductive specialists)
- Thyroid disease
Training and Certification
Endocrinologists are medical doctors and therefore must have a medical degree , Doctor of Medicine (MD) or Doctor of Osteopathic Medicine (DO). The first two years of medical school are mainly face-to-face studies. The last two years have involved changing doctors at different hospitals to learn about different areas of medicine.
Upon graduation from medical school, graduates must pass the United States Medical Licensing Examination (USMLE) to become licensed in the state in which they choose to practice. They will then begin their postdoctoral training, completing a three-year residency in Internal Medicine, Pediatrics, or Gynecology.
Towards the end of his residency, an endocrinologist candidate was applying for a two- to three-year fellowship in endocrinology. Scholarship programs vary, with some offering general training. while others focus on pediatrics or reproduction and infertility. Endocrinologists must be certified by the American Board of Internal Medicine (ABIM). Peer-reviewed exams consist of written tests.
To renew a medical license, an endocrinologist must participate in continuing medical education (CME) programs and maintain a certain number of teaching hours. Depending on the state and medical specialty, licenses are renewed every 7 to 10 years.
If you are referred to an endocrinologist, it is because the hormonal disorder or related condition is outside the scope of the referring physician's practice.
To make the most of your appointment, arrive early and bring the lab tests or imaging tests that are relevant to your condition. You should also ask your healthcare provider for the necessary files prior to your visit.
An appointment usually begins with a detailed examination of your symptoms, medical history, family history, and any medications you are taking. It is often helpful to write these things down in advance so you don't forget or lose them.
To better understand your condition and what tests and treatments are used, don't be afraid to ask as many questions as necessary. They may include:
- What experience have you had with this condition?
- How much of your practice is devoted to this state?
- What should I expect after starting treatment?
- What are the possible risks and complications?
- What is the success rate of the treatment?
- When can I know if the treatment is successful?
- Will the treatment affect my performance?
- Who should I call if there is a problem even at night?
- What can I do to improve my condition?
- What can happen if I refuse treatment?
- Are there alternatives to consider?
To find a board certified endocrinologist, visit the ABIM verification portal .
Finally, be sure to check if the endocrinologist and lab are your insurance company's service providers. Otherwise, you will almost certainly pay more and, in some cases, the full amount of the bill.
Get the word of drug information
Endocrinologists often choose a profession because it does not affect just one organ system or one disease. Rather, endocrinology studies the relationship between multiple organs and how each contributes to the development of disease. The profession requires three-dimensional thinkers who are naturally curious and capable of looking at a problem from all angles.
The practice itself generally operates during normal business hours. Most tests and procedures are done in the office. Unless the doctor specializes in cancer surgery or treatment, the more invasive procedures are usually outsourced.
Endocrinologists in the United States earned an average of $ 212,000 in 2018, according to Medscape's annual compensation report . Approximately 73% of them are in private practice in a profession dominated by women.