chapter 33 anti diabetic drugs - week 3 Flashcards
diabetes
Often regarded as a syndrome rather than a disease
Two types
Type 1
Type 2
diabetes signs and symptoms
Signs and symptoms
Elevated fasting blood glucose (higher than 7 mmol/L) or a hemoglobin A1c (HbA1c) level greater than or equal to 6.5%
Polyuria
Polydipsia
Polyphagia
Glycosuria
Weight loss
Fatigue
Blurred vision
diabetes signs and symptoms
Signs and symptoms
* Elevated fasting blood glucose (higher than 7 mmol/L) or a hemoglobin A1c (HbA1c) level greater than or equal to 6.5%
* Polyuria
* Polydipsia
* Polyphagia
* Glycosuria
* Weight loss
* Fatigue
* Blurred vision
type 1 diabetes
- Lack of insulin production, or production of defective insulin
- Affected patients need exogenous insulin.
- Fewer than 10% of all cases are type 1.
Complications
* Diabetic ketoacidosis
* Hyperosmolar hyperglycemic state
type 2
- Most common type (90% of all cases)
- Caused by insulin deficiency and insulin resistance
Many tissues are resistant to insulin.
* Reduced number of insulin receptors
* Insulin receptors less responsive
Several comorbid conditions
* Obesity
* Coronary heart disease
* Dyslipidemia
* Hypertension
* Microalbuminemia (protein in the urine)
* Increased risk for thrombotic (blood clotting) events
* These comorbidities are collectively referred to as metabolic syndrome or cardiometabolic syndrome.
gestational diabetes
- Hyperglycemia that develops during pregnancy
- Insulin must be given to prevent birth defects.
- Usually subsides after delivery
- 30% of patients may develop type 2 diabetes within 10 to 15 years.
major long term complications of both types of diabetes
Macrovascular (atherosclerotic plaque)
Coronary arteries
Cerebral arteries
Peripheral vessels
Microvascular (capillary damage)
Retinopathy
Neuropathy
Nephropathy
screening for diabetes
Prediabetes
Categories of increased risk
* HbA1c of 6.0 to 6.4%
* Fasting plasma glucose levels higher than or equal to 6.1 mmol/L but less than 6.9 mmol/L
* Impaired glucose tolerance test (oral glucose challenge)
Screening recommended every 3 years for all patients 40 years of age and older
nonpharmacologinal treatment interventions
Type 1: Always requires insulin therapy
Type 2
* Weight loss
* Improved dietary habits
* Smoking cessation
* Reduced alcohol consumption
* Regular physical exercise
glyemic goal of treatment
- HbA1c of less than 7%
- Fasting blood glucose goal for diabetic patients: 4 to 7 mmol/L
- 2-hour postprandial target of 5 to 10 mmol/L
treatment for diabetes
** Type 1**
Insulin therapy
** Type 2**
Lifestyle changes
Oral drug therapy
Insulin when the above no longer provide glycemic control
types of antidiabetic drugs
- Insulins
- Oral hypoglycemic drugs
- A combination of oral antihypoglycemic and insulin controls glucose levels.
- Some new injectable hypoglycemic drugs may be used in addition to insulin or antidiabetic drugs.
insulins
- Function as a substitute for the endogenous hormone
- Effects are the same as those of normal endogenous insulin
Restores the diabetic patient’s ability to: - Metabolize carbohydrates, fats, and proteins
- Store glucose in the liver
- Convert glycogen to fat stores
human insulin
Human insulin
Derived using recombinant deoxyribonucleic acid (DNA) technologies
Recombinant insulin produced by bacteria and yeast
Goal: tight glucose control
To reduce the incidence of long-term complications
rapid acting treatment for types 1 adn 2 diabetes
Rapid-acting treatment for types 1 and 2 diabetes
* Most rapid onset of action (10 to 15 minutes)
* Peak: 1 to 2 hours
* Duration: 3 to 5 hours
* Patient must eat a meal after injection
* Insulin lispro (Humalog®)
* Action similar to that of endogenous insulin
* Insulin aspart (NovoRapid®)
* Insulin glulisine (Apidra®)
* May be given subcutaneously or via continuous subcutaneous infusion pump (but not intravenously)
short acting insulins
- Regular insulin (Humulin R®, Novolin ge Toronto®)
- Routes of administration: intravenous (IV) bolus, IV infusion, intramuscular, subcutaneous
- Onset (subcutaneous route): 30 minutes
- Peak (subcutaneous route): 2 to 3 hours
- Duration (subcutaneous route): 6.5 hours
intermediate acting insulins
Insulin isophane suspension (also called NPH)
Cloudy appearance
Often combined with regular insulin
Onset: 1 to 3 hours
Peak: 5 to 8 hours
Duration: up to 18 hours
long aacting insulins
Insulin glargine (Lantus®)
Clear, colourless solution
Constant level of insulin in the body
Usually dosed once daily
Can be dosed every 12 hours
Referred to as basal insulin
Onset: 90 minutes
Peak: none
Duration: 24 hours
Insulin detemir
Duration of action is dose dependent.
Lower doses require twice-daily dosing.
Higher doses may be given once daily.
fixed combination insulins
Each contains two different insulins, fixed combinations
* One intermediate-acting type
* Either one rapid-acting type (Humalog, NovoLog) or one short-acting type (Humulin)
Humulin 30/70
Novolin 30/70, 40/60, 50/50
NovoMix® 30
Humalog Mix25®
Humalog Mix50®
sliding scale insulin dosing
- Subcutaneous rapid-acting (lispro or aspart) or short-acting (regular) insulins are adjusted according to blood glucose test results.
- Typically used in hospitalized diabetic patients or those on total parenteral nutrition or enteral tube feedings
- Subcutaneous insulin is ordered in an amount that increases as the blood glucose increases.
- Disadvantage: Delays insulin administration until hyperglycemia occurs, resulting in large swings in glucose control.
- Recent research does not support sliding-scale use; nonetheless, sliding scale is still commonly used.
basal bolus insulin dosing
- Preferred method of treatment for hospitalized patients with diabetes
- Mimics a healthy pancreas by delivering basal insulin constantly as a basal and then as needed as a bolus
- Basal insulin is a long-acting insulin (insulin glargine).
- Bolus insulin (insulin lispro or insulin aspart)
injectable antidiabetic drugs
Amylin agonist
pramlintide (Symlin®)
Incretin mimetics
exenatide (Byetta®)
liraglutide (Victoza®)
oral antidibetic drug recommendation type 2
2013 Canadian Diabetes Association recommendations
New-onset type 2 diabetes treatment
Lifestyle interventions
Oral biguanide drug metformin
If lifestyle modifications and the maximum tolerated metformin dose do not achieve the recommended A1c goals after 3 to 6 months, additional treatment should be given with dipeptidyl peptidase4 (DPP-4) inhibitors and glucagonlike peptide 1 (GLP-1) receptor agonists (liraglutide, exenatide, abliglutide) or insulin.
biganide
Biguanide
* metformin (Glucophage)
* First-line drug and the most commonly used oral medication for the treatment of type 2 diabetes
* Not used for type 1 diabetes
Adverse effects
Abdominal bloating, nausea, cramping, a feeling of fullness, and diarrhea
Metallic taste, hypoglycemia, and a reduction in vitamin B12 levels after long-term use
Lactic acidosis is an extremely rare complication.
biganide
Biguanide
* metformin (Glucophage)
* First-line drug and the most commonly used oral medication for the treatment of type 2 diabetes
* Not used for type 1 diabetes
Adverse effects
Abdominal bloating, nausea, cramping, a feeling of fullness, and diarrhea
Metallic taste, hypoglycemia, and a reduction in vitamin B12 levels after long-term use
Lactic acidosis is an extremely rare complication.
sulphonylureas
- Second generation: glimepiride (Amaryl), gliclazide (Diamicron), glyburide (DiaBeta)
- Adverse effects: hypoglycemia, weight gain, skin rash, nausea, epigastric fullness, and heartburn
sglinide
repaglinide (GlucoNorm®), nateglinide (Starlix®)
Indication: type 2 diabetes
PO
thiaxolidinediones
pioglitazone (Actos®)
rosiglitazone (Avandia®)
Insulin-sensitizing drugs
Indication: type 2 diabetes
PO
a-glucosidease inhibitor
acarbose (Glucobay)
Indication: type 2 diabetes
dipeptidyl peptidase DDPP-4 inhibiotrs
sitagliptin (Januvia®)
saxagliptin (Onglyza®)
linagliptin (Tradjenta®)
alogliptin (Nesina®)
injectable anitdiabetic drugs mechanism of action
Amylin agonist
* Mimics the natural hormone amylin
* Slows gastric emptying
* Suppresses glucagon secretion, reducing hepatic glucose output
* Used when other drugs have not achieved adequate glucose control
* Subcutaneous injection
Incretin mimetic
* Mimics the incretin hormones
* Enhances glucose-driven insulin secretion from β cells of the pancreas
* Used only for type 2 diabetes
* Exenatide: injection pen device
injectable antidiabetic drug adverse effects
Amylin agonist
* Nausea, vomiting, anorexia, headache
Incretin mimetics
* Nausea, vomiting, and diarrhea
* Rare cases of hemorrhagic or necrotizing pancreatitis
* Weight loss
sodium glucode cotransport inhibiotrs
- A decrease in blood glucose caused by an increase in renal glucose excretion.
- This inhibitor is a new class (2014) of oral drugs for the treatment of type 2 diabetes.
- canaglifozin (Invokana®), dapaglifozin (Forxiga®)
- Action: work independently of insulin to prevent glucose reabsorption from the glomerular filtrate, resulting in a reduced renal threshold for glucose and glycosuria
- Most frequently reported adverse effects include vaginal yeast infections and urinary tract infections.
- Other effects: may increase insulin sensitivity and glucose uptake in the muscle cells and decrease gluconeogenesis
- Results: improved glycemic control, weight loss, and a low risk of hypoglycemia
hypoglyemicca
Abnormally low blood glucose level (below
4 mmol/L)
Mild cases can be treated with diet—higher intake of protein and lower intake of carbohydrates—to prevent rebound postprandial hypoglycemia.
hypoglycemia symptoms
Adrenergic
Anxiety, tremors, sensation of hunger, palpitations, sweating
Central nervous system
Difficulty concentrating, confusion, weakness, drowsiness, vision changes, difficulty speaking, dizziness and headache
Later signs
Hypothermia, seizures
Coma and death will occur if not treated
glucose elevating drugs
- Oral forms of concentrated glucose
- Gel, liquid, or tablet form
- 50% dextrose in water (D50W)
- Glucagon
Before giving drugs that alter glucose levels, obtain and document:
- A thorough history
- Vital signs
- Blood glucose levels, HbA1c level
- Potential complications and drug interactions
Before giving drugs that alter glucose levels:
Assess the patient’s ability to consume food.
Assess for nausea or vomiting.
Hypoglycemia may be a problem if antidiabetic drugs are given and the patient does not eat.
If a patient is to take nothing by mouth (NPO) for a test or procedure, consult the primary care provider to clarify orders for antidiabetic drug therapy.
Keep in mind that overall concerns for any patient with diabetes increase when the patient:
Is under stress
Is pregnant or lactating
Has an infection
Has an illness or trauma
Thorough patient education is essential regarding:
Disease process
Diet and exercise recommendations
Self-administration of insulin or oral drugs
Potential complications
When insulin is ordered, ensure:
Correct drug
Correct route
Correct type of insulin
Correct dosage
Insulin order and prepared dosages are second-checked with another registered nurse (or per agency policy).
before giving insulin
Insulin
* Check blood glucose level before giving insulin.
* To mix suspensions, roll vials between hands instead of shaking them.
* Ensure correct storage of insulin vials.
* Only use insulin syringes, calibrated in units, to measure and give insulin.
* * Ensure correct timing of insulin dose with meals.
* * When drawing up two types of insulin in one syringe, always withdraw the regular or rapid-acting (clear) insulin first.
* Provide thorough patient education regarding self-administration of insulin injections, including timing of doses, monitoring of blood glucose levels, and injection site rotations.
oral anitdiabetic drugs
Oral antidiabetic drugs
* Always check blood glucose levels before administering.
* Usually given 30 minutes before meals
* α-Glucosidase inhibitors are given with the first bite of each main meal.
* Metformin is taken with meals to reduce gastrointestinal effects.
* Metformin will need to be discontinued if the patient is to undergo studies with contrast dye, because of possible renal effects; check with the prescriber.
if hypoglyemica occurs…
Assess for signs of hypoglycemia.
If hypoglycemia occurs:
* Administer oral form of glucose if the patient is conscious.
* Give the patient glucose tablets, liquid, or gel; corn syrup; honey; fruit juice or nondiet soft drink; or have the patient eat a small snack, such as crackers or a half sandwich.
* Deliver D50W or IV glucagon if the patient is unconscious.
* Monitor blood glucose levels.
