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Endocrinology Specialists of McKinney is located in McKinney, Texas.  Dr. Vivienne Yoon and Dr. Jennifer St. John are board certified in Internal Medicine, Endocrinology, Diabetes, and Metabolism.  Our physicians provide consultation, diagnosis and management of endocrine and metabolic diseases, including:

  • Diabetes mellitus and obesity
  • Disorders affecting the pituitary, thyroid, adrenal cortex and reproductive organs
    • Thyroid Cancer
    • Parathyroid Cancer
  • Calcium and skeleton mineralization and metabolism
  • Hypertension due to endocrine causes
  • Disorders affecting cholesterol and lipoprotein metabolism in relation to atherosclerosis

At Endocrinology Specialists of McKinney, we realize the importance of involving our patients in their treatment plan.  We strive to offer innovative management and treatment options that are individualized according to our patient's specific condition.

Endocrine and Metabolic Disorders

Endocrine disorders involve the body's over -or- under production of certain hormones, while metabolic disorders affect the body's ability to process certain nutrients and vitamins.

Endocrine disorders include hypothyroidism, diseases of the parathyroid gland, diabetes mellitus, diseases of the adrenal glands (including Cushing's syndrome and Addison's disease), and ovarian dysfunction (including polycystic ovary syndrome ), among others.  Some examples of metabolic disorders include hyperlipidemia and rickets.​​

Hours of Operation

Monday - Friday
8:00 am - 5:00 pm