Chapter 32: Antidiabetic Drugs
Diabetes Mellitus
A complex disorder of carbohydrate, fat, and protein metabolism resulting from the lack of insulin secretion by the beta cells of the pancreas or from defects of the insulin receptors; it is commonly referred to simply as diabetes. There are two major types of diabetes: type 1 and type 2.
Diabetic Ketoacidosis (DKA)
A severe metabolic complication of uncontrolled diabetes that, if untreated, leads to diabetic coma and death.
Gestational Diabetes
Diabetes that develops during pregnancy. It may resolve after pregnancy but may also be a precursor of type 2 diabetes in later life.
Glucagon
A hormone produced by the alpha cells in the islets of Langerhans that stimulates the conversion of glycogen to glucose in the liver.
Glucose
One of the simple sugars that serves as a major source of energy. It is found in foods (e.g., refined sweets) and also is the final breakdown product of complex carbohydrate metabolism in the body; it is commonly referred to as dextrose.
Glycogen
A polysaccharide that is the major carbohydrate stored in animal cells.
Glycogenolysis
The breakdown of glycogen to glucose.
Hemoglobin A1C (A1C)
Hemoglobin molecules bound to glucose molecules; blood levels of hemoglobin A1C are used as a diagnostic measure of average daily blood glucose levels in the monitoring and diagnosing of diabetes; it is also called glycosylated hemoglobin and most commonly referred to as A1C.
Hyperglycemia
A fasting blood glucose level of 126 mg/dL or higher or a nonfasting blood glucose level of 200 mg/dL or higher.
Hyperosmolar Hyperglycemic Syndrome (HHS)
A metabolic complication of uncontrolled type 2 diabetes, similar in severity to diabetic ketoacidosis but without ketosis and acidosis.
Hypoglycemia
A blood glucose level of less than 70 mg/dL, or above 50 mg/dL with signs and symptoms of hypoglycemia.
Insulin
A naturally occurring hormone secreted by the beta cells of the islets of Langerhans in the pancreas in response to increased levels of glucose in the blood.
Ketones
Organic chemical compounds produced through the oxidation of secondary alcohols (e.g., fat molecules), including dietary carbohydrates.
Polydipsia
Chronic excessive intake of water; it is a common symptom of uncontrolled diabetes.
Polyphagia
Excessive eating; it is a common symptom of uncontrolled diabetes.
Polyuria
Increased frequency or volume of urinary output; it is a common symptom of diabetes.
Type 1 Diabetes Mellitus
Diabetes mellitus that is a genetically determined autoimmune disorder characterized by a complete or nearly complete lack of insulin production; it most commonly arises in children or adolescents.
Type 2 Diabetes Mellitus
Diabetes mellitus that most commonly presents in adults and is becoming more common in children and adolescents due to inactivity and weight gain. The disease may be controlled by lifestyle modifications, oral drug therapy, and/or insulin, but patients are not necessarily dependent on insulin therapy.
Pancreas
It is both an exocrine gland (secreting digestive enzymes through the pancreatic duct) and an endocrine gland (secreting hormones directly into the bloodstream and not through a duct)
Insulin
Is required in patients with type 1 diabetes
Exogenous Insulin
Functions as a substitute for the endogenous hormone. It serves to replace the insulin that is either not made or is made defectively in a diabetic patient.
Rapid Acting Insulin
Lispro (Humalog), Aspart (NovoLog), Glulisine (Apidra)
These have the most rapid onset of action as well as a shorter duration of action than other insulin categories.
Short Acting Insulin
Regular (Humulin R)
The only Insulin classified as a short-acting insulin.
Intermediate Acting Insulin
Isophane Suspension (NPH Insulin)
The only available intermediate-acting insulin product.
Long Acting Insulin
Glargine (Lantus), Detemir (Levemir)
Long-acting insulin products.
Fixed-Combination Insulin
Humulin 70/30, Humulin 50/50, Novolin 70/30, Humalog Mix 75/25, Humalog 50/50, NovoLog 70/30
These products contains two different insulins; one intermediate-acting type and either one rapid-acting type or one short-acting type.
Sliding Scale
In this method, subcutaneous doses of rapid-acting or short-acting insulin are adjusted according to blood glucose test results.
Basal-Bolus Therapy
Is the attempt to mimic a healthy pancreas by delivering insulin constantly and then as needed.
Biguanide
Metformin is currently the only drug classified as this. It is considered a first-line drug and is the most commonly used oral drug for the treatment of type 2 diabetes.
Sulfonylureas
These are the oldest group of oral antidiabetic drugs. Those currently used are second-generation drugs and have a better potency and adverse effect profile than first-generation drugs.
Glinides
Repaglinide (Prandin) and nateglinide (Starlix) are currently the only two drugs in this class. They are structurally different but have a similar mechanism of action in that they also increase insulin secretion from the pancreas.
Thiazolidinediones (Glitazones)
This class of drugs acts by regulating genes involved in glucose and lipid metabolism. These drugs are also known to directly stimulate peripheral glucose uptake and storage, as well as to inhibit glucose and triglyceride production in the liver.
Alpha-Glucosidase Inhibitors
Less commonly used oral drugs are acarbose (Precose) and miglitol (Glyset). As the name implies, these drugs work by reversibly inhibiting the enzyme that is found in the small intestine.
Dipeptidyl Peptidase IV (DPP-IV) Inhibitors
Work by delaying the breakdown of incretin hormones by inhibiting the enzyme DPP-IV. Incretin hormones are released throughout the day and are increased after a meal.
Acarbose (Precose)
One of the two currently available alpha-glucosidase inhibitors.
Glipizide (Glucotrol)
A second-generation sulfonylurea drug. In contrast to another second-generation sulfonylurea, it has a very rapid onset and short duration of action, with no active metabolites.
Metformin (Glucophage)
Currently the only biguanide oral antidiabetic drug. It works by inhibiting hepatic glucose production and increasing the sensitivity of peripheral tissue to insulin.
Pioglitazone (Actos)
Classified as a glitazone or derivative, used alone or with a sulfonylurea, metformin, or insulin. It works by decreasing insulin resistance.
Repaglinide (Prandin)
One of two antidiabetic drugs classified as glinides, the other being nateglinide (Starlix). These drugs have a mechanism of action similar to that of the sulfonylureas in that they also stimulate the release of insulin from pancreatic beta cells.
Sitagliptin (Januvia)
Was the first DPP-IV inhibitor approved. It is an oral drug that selectively inhibits the action of DPP-IV, thus increasing concentrations of the naturally occurring incretins GLP-1 and GIP.
Amylin Agonists
Is a natural hormone secreted by the beta cells of the pancreas along with insulin in response to food. It functions to decrease postprandial plasma glucose levels, which it accomplishes in the following three ways: (1) It slows gastric emptying; (2) suppresses glucagon secretion and hepatic glucose production; and (3) increases satiety (sense of having eaten enough).
Incretin Mimetics
Are hormones released by the gastrointestinal tract in response to food, they do the following: stimulate insulin secretion; reduce postprandial glucagon production; slow gastric emptying; and increase satiety.
Liraglutide (Victoza)
Is an incretin mimetic drug, it enhances glucose-dependent insulin secretion, suppress elevated glucagon secretion, and slow gastric emptying.
Sodium Glucose Cotransorter Inhibitors (SGLT2 Inhibitors)
The inhibitors are a new class of oral drugs for the treatment of type 2 diabetes mellitus. They inhibit glucose reabsorption in the proximal renal tubules. They work independently of insulin to prevent glucose reabsorption, which results glycosuria.
Which is the most appropriate timing regarding the nurse's administration of a rapid-acting insulin to a hospitalized patient?
Which statement is appropriate for the nurse to include in patient teaching regarding type 2 diabetes?
The nurse monitoring a patient for a therapeutic response to oral antidiabetic drugs will look for
<ul> <li>hemoglobin A1C levels of less than 7%.</li> </ul> <br>
A patient with type 2 diabetes is scheduled for magnetic resonance imaging (MRI) with contrast dye. The nurse reviews the orders and notices that the patient is receiving metformin (Glucophage). Which action by the nurse is appropriate?
A patient with type 2 diabetes has a new prescription for repaglinide (Prandin). After 1 week, she calls the office to ask what to do, because she keeps missing meals. “I work right through lunch sometimes, and I'm not sure whether I need to take it. What do I need to do?” What is the nurse's best response?
When checking a patient's fingerstick blood glucose level, the nurse obtains a reading of 42 mg/dL. The patient is awake but states he feels a bit “cloudy-headed.” After double-checking the patient's glucose level and getting the same reading, which action by the nurse is most appropriate?
A patient is taking metformin for new-onset type 2 diabetes mellitus. When reviewing potential adverse effects, the nurse will include information about: (Select all that apply.)
A patient who has a new diagnosis of type 2 diabetes asks the nurse about a new insulin that can be inhaled. “Is there a reason I can't take that drug?” Which condition, if present in the patient, would be a concern?
Which is a rapid-acting insulin with an onset of action of less than 15 minutes?
Which long-acting insulin mimics natural, basal insulin with no peak action and a duration of 24 hours?
Which insulin can be administered by continuous intravenous (IV) infusion?
Assuming the patient eats breakfast at 8:30 AM, lunch at noon, and dinner at 6:00 AM, he or she is at highest risk of hypoglycemia after an 8:00 AM dose of NPH insulin at what time?
The nurse is preparing a patient for a computed tomography scan using iodine contrast media. Which medication should the nurse question if prescribed one day before the scheduled procedure?
Which oral hypoglycemic drug has a quick onset and short duration of action, enabling the patient to take the medication 30 minutes before eating and skip the dose if he or she does not eat?
Pramlintide (Symlin) is prescribed as supplemental drug therapy to the treatment plan for a patient with type 1 diabetes mellitus. What information should the nurse include when teaching the patient about the action of this medication?
The patient is prescribed 30 units of regular insulin and 70 units of insulin isophane suspension (NPH insulin) subcutaneously every morning. The nurse should provide which instruction to the patient for insulin administration?
When teaching a patient about insulin glargine (Lantus), which statement by the nurse about this drug is correct?
The nurse is providing education to a patient for the prescription glipizide (Glucotrol). The nurse explains this medication is more effective when administered at which time?
The nurse will instruct the patient to treat hypoglycemia with which drug?
When caring for a pregnant patient with gestational diabetes, the nurse should question a prescription for which drug?
Which information should the nurse include in a teaching plan for patients taking oral hypoglycemic drugs? (Select all that apply.)
Which actions describe the beneficial effects produced by sulfonylurea oral hypoglycemics? (Select all that apply.)