Endocrinology is the study of hormones and their normal & abnormal functions.

The endocrine system consists of 7 major endocrine glands namely – Pituitary, Thyroid, Parathyroids, Pancreas, Adrenals, Ovary & Testis. Also included in the Endocrine system are Vitamin D, Bone, Fat tissue, Muscle tissue, GI tract, Pineal gland. The major hormones produced by 7 major endocrine glands are as follows:

•  Pituitary – Growth hormone (GH), Thyroid-stimulating hormone (TSH), Luteinizing hormone (LH), Prolactin, Follicle-stimulating hormone (FSH), Adreno-cortico trophic hormone (ACTH), Anti-diuretic hormone (ADH)
•  Thyroid – Triiodothyronine (T3), Tetraiodothyronine (T4)
•  Parathyroids – Parathormone (PTH), Calcitonin
•  Pancreas – Insulin, Glucagon, Somatostatin
•  Adrenals – Cortisol, Aldosterone, DHEAS, Adrenaline, Nor-adrenaline
•  Testis – Testosterone, Estrogen
•  Ovary – Estrogen, Progesterone, Testosterone

Other glands and their hormones include:

•  Vitamin D
•  Pineal gland – Melatonin
•  GI tract – GLP-1, GIP, and VIP
•  Bone – FGF-23, sclerostin
•  Fat tissue – Leptin, Adiponectin

Hormonal problems result from either:

•  Excess production or action of a hormone
•  Less production or action of a hormone
•  Interference of one hormone into another hormone action

Common hormonal problems include:

•  Diabetes – less production or action of Insulin
•  Hypoglycemia – more production or action of Insulin
•  Hypothyroidism – less production of thyroid hormones
•  Hyperthyroidism – more production of thyroid hormones
•  Post-menopausal osteoporosis – decreased production of Estrogen at menopause
•  Short height – less production or action of Growth hormone
•  Acromegaly/gigantism – more production or action of Growth hormone
•  Addison’s disease – Less production of steroid hormone
•  Cushing’s syndrome – More production of steroid hormone
•  PCOS – more testosterone in females
•  Hirsutism – more testosterone in females
•  Gynecomastia – more estrogen in males
•  Low testosterone in males
•  Hypercalcemia – more production or action of PTH hormone
•  Hypocalcemia – less production or action of PTH hormone
•  SIADH – more production or action of ADH hormone
•  Diabetes insipidus – less production or action of ADH hormone
•  High blood pressure – more production of adrenal hormones
•  Low blood pressure – less production of adrenal hormones