Endocrine Flashcards
Drugs that impact the endocrine system:
Bisphosphonates (reviewed later in the course)
Antidiabetic agents (reviewed part 1)
Hypothalamic and pituitary hormones (reviewed part 2)
Exocrine pancreatic enzymes (reviewed part 2)
Thyroid and antithyroid agents (reviewed part 2)
Diabetes Mellitus (DM)
Chronic, progressive metabolic disorder resulting from abnormalities in glucose, protein, and fat metabolism
DM Type One
diabetes, which results from beta-cell destruction, leading to absolute insulin deficiency
DM Type 2
diabetes, which results from a progressive insulin secretory defect or insulin resistance
Diabetes resulting from other causes
e.g., genetic defects in beta-cell function or insulin action; diseases of the exocrine pancreas, such as cystic fibrosis; and drug- or chemical-induced
Gestational diabetes mellitus (GDM), which is diagnosed during
pregnancy
Insulin phamacodynamics
Binds at insulin receptor sites on cell membrane allowing glucose to enter cells
insulin acts on liver to
increase storage of glucose as glycogen
insulin promotes
protein synthesis on muscle cells
Inculin reduces
circulation of free fatty acids and promotes storage of triglycerides in adipose tissue
Rapid-acting examples and peak
lispro (Humalog), aspart (NovoLog), or glulisine (Apidra), onset about 5 minutes, peaks in 1 hour, duration about 4 to 5 hours
short acting examples and peak
regular“ (Humulin) insulin sometimes used around mealtime. Taken about 30 to 45 minutes before eating, peaks in 3 to 4 hours, duration 4 to 10 hours
Intermediate-acting: Name, peak, onset and duration
NPH mixed with protamine, delaying absorption; insulin looks cloudy and has to be mixed before it is injected; onset one-half to 1 hour, peak 4 to 10 hours, duration 12 to 24 hours
Long acting, name peak, onset, duration
glargine (Lantus),detemir (Levemir), degludec (Tresiba) insulins onset 2 to 4 hours, duration 24 hours with little or no peak
Insulin absorption determed by
type of insulin, injection site, and volume injected
insulin abdominal sites absorbes
50% more than other sites
insulin excretion
urine
inslusin should be injected with
standardized U 100/mL, needs U100 needles
Inslulin ADR
hypoglycemia, diabetic ketoacidosis
Watch alcohol use; increases hypoglycemia
Beta blockers mask hypoglycemia symptoms
Pregant women insulin
can use rapid- or short-acting insulin; does not cross placenta
Insulin aspart, insulin glargine, and insulin glulisine
insulin and hypothyroidism
delays insulin breakdown; therefore may require less insulin units
insulin and hyperthyroidism
increases renal clearance, requiring more insulin than baseline
Insulin monitoring
Glycohemoglobin, renal function, CBC
A1C test twice a year in patients who are meeting treatment goals and have stable glycemic controls
A1C test quarterly in patients whose treatment has changed/not meeting goals
Point-of-care testing for A1C allows for timely decisions on treatments changes
A1C as an average of the patients glucose in the last
90 days and comes in a percentage
goal for A1C for most nonpregnant adults
less than 7%
insulin patient education
Individualized goals for older adults with long-time diagnoses
Administration, understanding types of insulin
Glucose monitoring frequency and recording
Emergency plan for glucose readings and “flu”
Lifestyle management, diet, exercise
Injection site selection
Look at insulin peak, onset, duration, and names
chat in book
Insulin is dosed on a
total daily insulin need. Calculation is done that gives you a total daily dose. 50% goes into the short acting pool. That is divided between the three meals a day. The remainder is given as a long acting.
Insufficient production of endogenous insulin
Sulfonylureas: cause an increase in insulin production
Tissue insensitivity to insulin
Thiazolidinediones: improve insulin sensitivity
Biguanides: do the same
Impaired response of beta cells
Meglitinides: increase secretion of insulin
Excessive production of glucose by the liver drugs and MOA
Metformin: improves hepatic response to elevated blood glucose (BG), decreases glucose production, and decreases GI absorption
Alpha-glucosidase inhibitors: inhibit absorption of carbohydrate in GI tract
Impaired glucagon-like peptide-1 (GLP-1) activity: rapid intestinal glucose dumping
Use of dipeptidyl peptidase 4 (DPP-4) medications to slow inactivation
Continuous weight gain
DPP-4 may stop it or be weight neutral
Sulfonylureas examples
Glipizide (Glucotrol), glyburide (Diabeta), glimepiride (Amaryl)
Sulfonylureas
All stimulate insulin release from beta cells
All potentiate effects of antidiuretic hormone
Hypoglycemia is major side effect
Sulfonylureas Precautions and contraindications
Cross-sensitivity with sulfonamides or thiazide diuretics
Avoid in pregnant women
Older adults more sensitive to hypoglycemia events
Pediatric: use in children 10 to 18 years, but it is unlabeled
Sulfonylureas ADRs
Hypoglycemia, GI, dermatological rashes, syndrome of inappropriate antidiuretic hormone secretion, hemolytic anemia, leukopenia, thrombocytopenia, weight gain
Sulfonylureas Drug Interactions
many may increase or decrease hypoglycemic effect
Sulfonylureas Clinical use and dosing
Use second-generation agents most of the time.
Individualized dose progression is based on response.
Start with lowest dose and increase every 4 to 7 days.
Sulfonylureas neurogenic diabetes insipidus
Chlorpropamide is used off-label.
Sulfonylureas rational drug selection dosing
Age: chlorpropamide and glyburide used in older adults (use short-acting glipizide)
Cost: many generics available
Concurrent renal disease
Glipizide or tolbutamide, or glyburide
Concurrent insulin: only glimepiride FDA labeled for co-administration, but most second-generation agents used
Monitoring Sulfonylurea
HgA1C: baseline, then every 3 months while adjusting, then every 6 months
CBC at onset, then annual unless more if symptoms
Patient Education
Administration
ADR
Lifestyle managment
