Endocrine
9.1 Metabolic Regulation Introduction
Learning Objectives
- Understand the classifications and actions of endocrine system drugs
- Give examples of when, how, and to whom endocrine system drugs may be administered
- Identify the side effects and special considerations associated with endocrine system drug therapy
- Identify the considerations and implications of using endocrine system medications across the lifespan
- Apply evidence-based concepts when using the nursing process and clinical reasoning related to medications that affect the endocrine system
- Identify indications, side effects, and potential drug interactions associated with the use of herbal supplements
Key Terms
- A1C
- adrenal medulla
- aldosterone
- antidiuretic hormone
- basal insulin
- blood osmolarity
- diabetes insipidus
- exocrine gland
- general adaptation syndrome
- glycolysis
- hormones
- humoral stimuli
- hyperglycemia
- hypoparathyroidism
- hyperthyroidism
- hypothyroidism
- hypoglycemia
- hypoparathyroidism
- hypothalamic-pituitary-adrenal axis
- hypothalamus–pituitary complex
- hypothyroidism
- insulin
- mineralocorticoids
- negative feedback loop
- neural stimuli
- osmoreceptors
- parathyroid hormone
- prandial insulins
- tropic hormones
- type 1 diabetes
- type 2 diabetes
Have you ever wondered how your body controls functions such as digestion, metabolism, and the stress response? The endocrine system is always working behind the scenes, regulating various organs by releasing hormones and using feedback loops. This chapter will discuss medications that affect three of the major endocrine glands: the adrenal glands, the pancreas, and the thyroid. But before we get started with discussing medications, let’s review some key endocrine system concepts to understand the mechanism of action of endocrine medications.
A lab test used to assess long-term blood glucose levels over 3 months. The general A1C target level is less than 7%.
Neuroendocrine tissue composed of postganglionic sympathetic nervous system (SNS) neurons that are stimulated by the autonomic nervous system to secrete hormones epinephrine and norepinephrine.
A mineralocorticoid, released by the adrenal cortex, that controls fluid and electrolyte balance through the regulation of sodium and potassium.
ADH is released by the posterior pituitary in response to stimuli from osmoreceptors indicating high blood osmolarity. Its effect is to cause increased water reabsorption by the kidneys. As more water is reabsorbed by the kidneys, the greater the amount of water that is returned to the blood, thus causing a decrease in blood osmolarity. ADH is also known as vasopressin because, in very high concentrations, it causes constriction of blood vessels, which increases blood pressure by increasing peripheral resistance.
Long-acting (insulin glargine or insulin detemir) or intermediate-acting (NPH) insulin.
The concentration of solutes (such as sodium and glucose) in the blood.
A disease characterized by underproduction of ADH that causes chronic dehydration.
Gland that secretes digestive enzymes.
The pattern in which the body responds in different ways to stress: The alarm reaction (otherwise known as the “fight or flight response,” the stage of resistance, and the stage of exhaustion).
Stimulated by insulin, the metabolism of glucose for generation of ATP.
Chemical signals sent by the endocrine organs and transported via the bloodstream throughout the body where they bind to receptors on target cells and induce a characteristic response.
Changes in blood levels of non-hormone chemicals that cause an endocrine gland to release or inhibit a hormone to maintain homeostasis. For example, high blood sugar causes the pancreas to release insulin.
Elevated blood sugar.
Abnormally low blood calcium levels caused by parathyroid hormone deficiency, which may develop following thyroid surgery. Low blood calcium can cause muscle twitching, cramping, spasms, or convulsions; severe deficits can paralyze muscles, including those involved in breathing, and can be fatal.
Abnormally elevated blood level of thyroid hormones T3 and T4, often caused by a pituitary tumor, thyroid tumor, or autoimmune reaction in which antibodies overstimulate the follicle cells of the thyroid gland
Abnormally low blood levels of thyroid hormones T3 and T4 in the bloodstream.
A blood glucose level below 70 mg/dL; severe hypoglycemia refers to a blood glucose level below 40.
The hypothalamus stimulates the release of ACTH from the pituitary, which then stimulates the adrenal cortex to produce the hormone cortisol and steroid hormones important for the regulation of the stress response, blood pressure and blood volume, nutrient uptake and storage, fluid and electrolyte balance, and inflammation.
The “command center” of the endocrine system that secretes several hormones that directly produce responses in target tissues, as well as hormones that regulate the synthesis and secretion of hormones of other glands. In addition, the hypothalamus–pituitary complex coordinates the messages of the endocrine and nervous systems.
A hormone that facilitates the uptake of glucose into skeletal and adipose body cells.
Hormones released by the adrenal cortex that regulate body minerals, especially sodium and potassium, that are essential for fluid and electrolyte balance. Aldosterone is the major mineralocorticoid.
Characterized by the inhibition of further secretion of a hormone in response to adequate levels of that hormone.
Released in response to stimuli from the nervous system. For example, the activation of the release of epinephrine and norepinephrine in the fight-or-flight response is stimulated by the sympathetic nervous system.
Specialized cells within the hypothalamus that are sensitive to the concentration of sodium ions and other solutes in the bloodstream.
The hormone released by parathyroid glands; involved in the regulation of blood calcium levels.
During or relating to the eating of food.
Hormones that turn on or off the function of other endocrine glands, including ACTH, FSH, LH, and TSH.
An autoimmune disease that affects the beta cells of the pancreas so they do not produce insulin; thus, synthetic insulin must be administered by injection or infusion.
A condition where the body’s cells become resistant to the effects of insulin. Over time, the beta cells become exhausted and if blood glucose levels cannot be controlled through a healthy diet and exercise, then oral diabetic medication must be implemented and eventually insulin administration may be required.