Diabetes Mellitus & Pancreatic Hormones Flashcards
Pancreatic Enzymes: Uses & Pharmacodynamics
Uses: cystic fibrosis and pancreatitis
- some bariatric procedures require supplements
Pharmacodynamics
- inactivated by pH values less than 4; do not crush or chew
- – sprinkled on food if powdered form
- Taken immediately before or with a meal
Pancreatic Enzymes: Pharmacokinetics & Precautions
Absorption: none, because it acts locally in GI tract
Excretion: feces
Pancrelipase made form pork; pancreatin made from pork, beef, or vegetable sources
Precautions: antacids decrease effectiveness; decreases absorption of oral iron
Pancreatic Enzymes: ADRs & Rational Drug Selection
ADRs: skin- irritation, rashes; GI- stomatitis, nausea; high doses- hyperuricosuria, hyperuricemia
Rational Drug selection: watch products because they are NOT bioequivalent; most old formulas are no longer FDA approved
Pancreatic Enzymes: Monitoring
Pancreatitis: contraindicated during acute exacerbations of chronic illness
Hypersensitivities: may need products from vegetable sources
Growth charts, albumin, cholesterol, glucose, CBC, iron levels. serum uric acid
Steatorrhea: rates and intensity help monitor dosing
Pancreatic Enzymes: Info
Info:
- Each drug is specified in lipase, protease, and amylase units
- Drugs are prescribed in units of lipase
- Many older formulations are not available in FDA-approved source, so finding the right dosing is more complex; this is improving over time
Pancreatic Enzymes: Patient Education
- Do not chew, crush, or drink with water
- Avoid leaving in mouth
- Enteric-coated formulations should not be mixed with alkaline foods prior to ingestion
- If powder spills, wash off skin immediately
- With infants/toddlers: watch for aspiration, inhalation
- Lifestyle management: follow dietary guidelines
Endocrine Pancreatic Hormones- Insulin: Pharmacodynamics
Binds at insulin receptor sites on cell membrane allowing glucose to enter cells
Acts on liver to increase storage of glucose as glycogen
Promotes protein synthesis on muscle cells
Reduces circulation of free fatty acids and promotes storage of triglycerides in adipose tissue
Endocrine Pancreatic Hormones- Insulin: Rapid Acting
Lispro (Humalog), aspart (Novolog), or glulisine (Apidra)
Onset about 5 minutes, peaks in 1 hour, duration about 4-5 hours
Endocrine Pancreatic Hormones- Insulin: Short-acting
“Regular” (Humulin) insulin
Sometimes used around mealtime
Taken about 30-45 minutes before eating, peaks in 3-4 hours, duration 4-10 hours
Endocrine Pancreatic Hormones- Insulin: intermediate-acting
Normal pressure hydrocephalus mixed with protamine, delaying absorption
Insulin looks cloudy and has to be mixed before it is injected
Onset one-half to 1 hour, peaks 4-10 hours, and duration 12-24 hours
Endocrine Pancreatic Hormones- Insulin: Long-acting
Glargine (Lantus), detemir (Levemir), degludec (Tresiba)
Onset 2-4 hours, duration 24 hours with little or no peak
Endocrine Pancreatic Hormones- Insulin: Pharmacokinetics
Absorption determined by type of insulin, injection site, and volume injected
Abdominal site absorbs 50% more than other sites
Metabolism: induced CYP1A2
Excretion: urine
Watch for standardized U 100/mL, needs U100 needles
Endocrine Pancreatic Hormones- Insulin: ADRs
Hypoglycemia, diabetic ketoacidosis
- watch alcohol use, increases hypoglycemia
- beta blockers mask hypoglycemia symptoms
Pregnant women can use rapid- or short-acting insulin- does not cross placenta
- Insulin aspart, insulin lispro, and insulin glulisine
Hypothydroidism
- Delays insulin breakdown; therefore, may require less insulin units
Hyperthyroidism
- Increases renal clearance, requiring more insulin than baseline
Endocrine Pancreatic Hormones- Insulin: Monitoring
Glycohemoglobin, renal function, CBC
- A1c test twice a year in patients who are meeting treatment goals and have stable glycemic control
- A1c test quarterly in patients whose treatment has changed/not meeting goals
- Point-of-care testing for A1c allows for timely decisions on treatment changes
Endocrine Pancreatic Hormones- Insulin: Patient Education
Goal A1c less than 7% for most nonpregnant adults
- 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
Oral Diabetic Agents: Mechanisms
Type 2 DM more than just insulin resistance
- 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
Oral DM Medications: For excessive production of glucose by liver
Metformin- improves hepatic response to elevated blood gas, decreases glucose production, and decreases GI absorption
Alpha-glucosidase inhibitors: inhibit absorption of carbohydrate in GI tract
Oral DM Medications: For impaired glucagon-like peptide-1 (GLP-1) activity
(Rapid Intestinal Dumping)
Use of dipeptidyl peptidase 4 (DPP-4) medications to slow inactivation
- may stop weight gain or be weight neutral as well
Sulfonylureas
Glipizides (Glucotrol), glyburide (diabeta), glimepiride (Amaryl)
All stimulate insulin release from beta cells
All potentiate effects of antidiuretic hormone
Hypoglycemia is a major side effect
Sulfonylureas: Precautions and Contraindications
Cross-sensitivity with sulfonamides or thiazide diuretics
Avoid in pregnant women
Old adults more sensitive to hypoglycemia events
Pediatric: Use in children 10-18 years, but it is unlabeled
Sulfonylureas: ADRs and Drug Interactions
ADRs: hypoglycemia, GI, dermatological rashes, syndrome of inappropriate antidiuretic hormone secretion, hemolytic anemia, leukopenia, thrombocytopenia, weight gain
Drugs interactions: many
- may increase or decrease hypoglycemia effect
Sulfonylureas: Clinical Use and Dosing for DM
- Use second-generation agents most of the time
- Individualized dose progression is based on response
- Start with lowest dose and increase every 4-7 days
- 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
Sulfonylureas: Monitoring & Patient Education
Monitoring
- HgA1c: baseline, then every 3 months while adjusting, then every 6 months
- CBC at onset, then annual, more if symptoms
Patient Education
- Administration, ADRs, Lifestyle management