Exam 3- Endocrine System Flashcards
(39 cards)
Biguanides
Increases insulin sensitivity, Reduces hepatic glucose production, and decreases glucose absorption in the gut.
Caution in liver patients due to risk for lactic acidosis
Metformin (Glucophage)
•Indicated for the treatment of DMII
Thiazolidinediones (TZDs) (-litazone)
•Decrease insulin resistance through activation of insulin-responsive genes in the nuclei of tissues important for insulin action
- Used in the treatment of type 2 DM
- Adverse effects – peripheral edema, liver failure, heart failure
•Pioglitazone (Actos), rosiglitazone (Avandia)
Sulfonylureas (-ide)
•Reduce blood glucose by stimulating insulin release from pancreatic beta cells
•First-generation –Chlorpropamide (Diabinese) –Tolbutamide (Orinase) •Second-generation –Glyburide (Diabeta) –Glipizide (Glucatrol) –Glimepride (Amaryl)
Initially used as first-line drugs in the treatment of type 2 DM
•Extensively protein bound
•Side effects – hypoglycemia
Meglitinide Analogues
- Nateglinide (Starlix), Repaglinide (Prandin)
- Oral hypoglycemic drugs used in the treatment of type 2 DM
- Stimulate insulin release from pancreas
- 98% protein bound; biotransformed by CYP450
- Drug interactions
- Patient education
Alpha-glucosidase Inhibitors
•Acarbose (Precose), miglitol (Glyset)
•Lower postprandial BS in the treatment of type 2 DM
•Inhibit alpha-glucosidase enzymes in the intestine
–Decreases the amount of glucose available for absorption in the GI tract
•Very little absorbed systemically
•Side effects – GI
Amylin Agonists
•Pramlintide (Symlin)
•Injectable antihyperglycemic used in the treatment of type 1 and type 2 DM patients treated with insulin
•A synthetic analogue of human amylin
–Neuropeptide hormone synthesized by pancreatic beta cells
•Biotransformed in the kidneys
•Side effects – hypoglycemia, GI
GLP-1 Agonist (-atide)
An incretin
Directly Increase insulin secretion from the beta cells and inhibit the release of glucagon.
•Exanatide (Byetta), Albiglutide (Tanzeum), Tulaglutide (Trulicity), Liraglutide (Victoza)
•Indicated as adjunct therapy in patients with type 2 DM who are using metformin, a sulfonylurea (or both) who have not achieved adequate BS control
•Glucagon-like peptide 1 (GLP-1) – deficient in diabetics
•Side effects – GI, gradual weight loss
DPP-4 Antagonists
•Sitagliptin (Januvia), saxagliptin (Onglyza), linagliptin (Tradjenta), alogliptin (Nesina)
•Indicated for the treatment of type 2 DM
•Inhibits dipeptidyl peptidase 4 (DDP-4)
–Enzyme responsible for degradation of incretins
•Side effects - URI
Thyroid replacement hormones
Levothyroxine (Synthroid, Levoxyl, T4), liothyronine (Cytomel T3)
•Levothyroxine is the drug of choice for replacement of thyroid hormone (T4)
•Absorption increased on an empty stomach
•Metabolized in the liver; highly protein bound
•Few adverse effects
•Patient education
Antithyroid drugs
Propylthiouracil (PTU), methimazole (Tapazole)
•First-line drugs in the treatment of hyperthyroidism or thyrotoxicosis
•Inhibit the synthesis of thyroid hormones
•Crosses placental membranes
•Side effects – rash, leukopenia
•Drug interactions
Radioactive iodine
Sodium idodide131
•Radioactive iodine (RAI) is used in the treatment of hyperthyroidism in older adults – also in diagnosis of thyroid conditions
•The thyroid gland actively absorbs iodine
–RAI disrupts the function of thyroid cells → thyroid hormones are no longer produced
•Side effects – few; iatrogenic hypothyroidism
Insulin
•Rapid-acting insulin – lispro (Humalog)
•Fast-acting insulin – regular
•Intermediate-acting insulin – Humulin N
•Long-acting insulin – insulin glargine, insulin detemir
•Indicated for the treatment of diabetes when glucose and hemoglobin A1C goals are not met with other treatments
•Insulin produced through recombinant DNA technology
Adverse effects – hypoglycemia, dawn phenomenon
•Drug interactions
•Dosage regimen
•Lab considerations
•Patient education
Signs of hypoglycemia
decreased levels of consciousness, hunger, diaphoresis, weakness, dizziness, and tachycardia. (defined as BG less than 70).
Signs of hyperglycemia
polyuria, polydipsia, polyphagia, weight loss and fatigue, vomiting, dehydration, ketone odor to the breath, and abdominal pain. Indications may precede DKA.
Signs of ketoacidosis
drowsiness, dim vision, and Kussmauls respirations. Symptoms of hyperglycemia may precede DKA and give warning of its impending occurrence include
How does metformin work?
increases peripheral glucose uptake and utilization (insulin sensitivity), decreases hepatic glucose production, and decreases intestinal absorption of glucose. Together, these actions address the primary pathological defects of type 2 diabetes to improve glucose tolerance and lower both basal and postprandial plasma glucose levels
What diagnostic testing is needed before initiating therapy and throughout treatment with metformin?
Before initiating therapy and at least annually thereafter, assess renal function. Assessment is by serum creatinine and CCr initially and then by serum creatinine annually. Patients who have been previously well controlled on metformin who are no longer controlled or who develop illnesses that place them at risk for metabolic acidosis should be assessed for evidence of ketoacidosis or lactic acidosis
What is the action of gliptin?
The action of gliptins is different from that of other antihyperglycemic agents because gliptins act on the incretin hormone system to have an indirect effect on increasing insulin production. Although the improvement in glycemic control is moderate and no more than with metformin, gliptins are well tolerated, have a low risk for hypoglycemia, are weight neutral, and can be given orally
How do GLP agonists work?
Glucagon-like peptide-1 is a naturally occurring peptide produced in the small intestine that potentiates glucose-stimulated insulin secretion. GLP-1 agonists directly bind to the GLP-1 receptor in the pancreatic beta cell and act as an incretin mimetic.
When should exenatide be administered?
Immediate-release exenatide is given about 60 minutes before morning and evening meals and doses should be at least 6 hours apart. Do not administer after a meal.
What are the adverse effects of propylthiouracil?
The most common serious adverse reaction to therapy with the thionamides is agranulocytosis and possible aplastic anemia. Drug-induced hepatitis and abnormal hair loss may occur.
What are the adverse effects of levothyroxine?
Adverse reactions other than those associated with hyperthyroidism due to overdose are rare. If the patient experiences indications of hyperthyroidism (increased heart rate, cardiac arrhythmias, chest pain, tremors, nervousness, insomnia, irritability, diarrhea, vomiting, weight loss, menstrual irregularities, or heat intolerance), the TSH level should be assessed and appropriate dosage adjustments made.
What is the recommended treatment for toxic goiter?
Patients with toxic goiter require higher doses of antithyroid drugs. Methimazole is initiated at a dose of 60 mg/d divided into three equal doses given 8 hours apart. Propylthiouracil is initiated with 600 to 900 mg/d in three equally divided doses given 8 hours apart. Maintenance doses are the same as for hyperthyroidism. Some treatment regimens give either medication for 1 month to “calm” the thyroid and then administer a dose of radioactive iodine.
What are the adverse effects of PTU and methimazole?
The most common serious adverse reaction to therapy with the thionamides is agranulocytosis and possible aplastic anemia. Drug-induced hepatitis and abnormal hair loss may occur with either drug. Less serious and less frequent adverse reactions to both thioamides include drowsiness, headache, paresthesias, vertigo, diarrhea, nausea, arthralgia, and a pruritic skin rash. The nausea and skin rash are more common with propyl -thiouracil, but there is an element of cross-sensitivity with metimazole.
