Chapter 32 Antidiabetic Drugs Flashcards
(141 cards)
1
Q
The pancreas is both an?
A
- exocrine gland (secreting digestive enzymes through the pancreatic duct)
- endocrine gland (secreting hormones directly into the bloodstream and not through a duct)
2
Q
Two main hormones that are produced by the pancreas are?
A
insulin and glucagon. Both hormones play an important role in the regulation of glucose homeostasis, specifically the use, mobilization, and storage of glucose by the body
3
Q
Glucose is one of the primary sources of energy for the cells of the body. It is also the simplest form of carbohydrate (sugar) found in the body and is often referred to as?
A
dextrose
4
Q
When the quantity of glucose in the blood is sufficient, the excess is stored as?
A
glycogen in the liver and, to a lesser extent, in skeletal muscle tissue, where it remains until needed. Glucose is also stored in adipose tissue as triglyceride body fat.
5
Q
When more circulating glucose is needed, glycogen—primarily that stored in the liver—is converted back to glucose through a process called?
A
glycogenolysis. The hormone responsible for initiating this process is glucagon. Glucagon has only minimal effects on muscle glycogen and adipose tissue triglyceride stores.
6
Q
Because of the critical role of the pancreas in producing and maintaining these two hormones, pancreatic or islet cell transplant are sometimes undertaken to treat?
A
type 1 diabetes that has not been successfully controlled by other means
7
Q
Insulin normally facilitates removal of?
A
glucose from the blood and its storage as glycogen in the liver
-Insulin also has a direct effect on fat metabolism. It stimulates lipogenesis and inhibits lipolysis and the release of fatty acids from adipose cells.
8
Q
Diabetes mellitus, more commonly referred to simply as diabetes, is primarily a disorder of?
A
carbohydrate metabolism that involves either a deficiency of insulin, a resistance of tissue (e.g., muscle, liver) to insulin, or both
9
Q
Two major types of diabetes mellitus are type 1 and type 2. Type 1 diabetes was previously called insulin dependent diabetes mellitus or juvenile-onset diabetes.
A
Little or no endogenous insulin is produced by individuals with type 1 diabetes, which affects only about 10% of all diabetic patients. Patients with type 1 diabetes usually are not obese. Insulin therapy is required for type 1 diabetics; patients with the cognitive and financial ability are encouraged to consider insulin pumps with continuous glucose monitoring.
10
Q
Type 2 diabetes was previously called?
A
non–insulindependent diabetes mellitus or adult-onset diabetes
11
Q
The current key diagnostic criterion for diabetes mellitus is?
A
hyperglycemia with a fasting plasma glucose (FPG) level of higher than 126 mg/dL or a hemoglobin A1C (A1C) level
greater than or equal to 6.5%
12
Q
The most common signs and symptoms of diabetes are?
A
elevated blood glucose level (fasting glucose level higher than 126 mg/dL) and polyuria, polydipsia, polyphagia, glucosuria, weight loss, blurred vision, and fatigue
13
Q
A new term, estimated average glucose (eAG) is a mathematical conversion of the A1C into an average blood glucose level in the units of measure seen by patients on glucose meters for self-monitoring (mg/dL). Similar to A1C, eAG evaluates a patient’s overall?
A
success at controlling glucose levels and helps patients understand the monitoring of their long-term treatment
14
Q
Type 1 diabetes mellitus is characterized by a lack of?
A
insulin production or by the production of defective insulin, which results in acute hyperglycemia. Affected patients require exogenous insulin to lower the blood glucose level and prevent diabetic complications
15
Q
When blood glucose levels are high but no insulin is present to allow glucose to be used for energy production, the body may?
A
break down fatty acids for fuel, producing ketones as a
metabolic by-product and resulting in diabetic ketoacidosis (DKA). DKA is a complex multisystem complication of uncontrolled diabetes.
16
Q
Another complication that is also triggered by extreme
hyperglycemia is?
A
hyperosmolar nonketotic syndrome (HNKS). The most common precipitator of DKA and HNKS is some type of physical or emotional stress. Both disorders can occur with diabetes of either type
17
Q
Type 2 diabetes mellitus accounts for at least 90% of all cases of diabetes mellitus. Type 2 diabetes mellitus is caused by?
A
both insulin resistance and insulin deficiency, but there is no absolute lack of insulin as in type 1 diabetes
18
Q
Type 2 diabetes is a multifaceted disorder. Although loss of blood glucose control is its primary hallmark, other conditions associated with it are?
A
obesity, coronary heart disease, dyslipidemia, hypertension, microalbuminuria, and an increased risk for thrombotic events
19
Q
The goal for patients with diabetes is a blood pressure less than?
-and low-density lipid less than?
A
- blood pressure less than 130/80 mmHg
- low-density lipid less than 100 mg/dL
20
Q
Gestational diabetes is a type of hyperglycemia that occurs in about 2% to 10% of pregnancies. Many patients are well controlled with diet, but the use of insulin may be necessary to decrease the risk of birth defects, hypoglycemia in the newborn, and high birth weight. As many as 30% of patients who experience gestational diabetes are estimated to develop?
A
type 2 diabetes within 10 to 15 years
21
Q
Adults 45 years of age and older should be screened for elevated FPG levels every?
A
3 years
22
Q
Patients diagnosed with type 1 diabetes always require insulin therapy. For patients with new-onset type 2 diabetes, lifestyle changes should be initiated as a first step in treatment.
A
Weight loss, improved dietary habits, smoking cessation, reduced alcohol consumption, and regular physical exercise are just a few examples of lifestyle changes
23
Q
The glycemic goal recommended by the American Diabetes Association (ADA) for diabetic patients is an?
A
A1C level of less than 7%
24
Q
The major classes of drugs used to treat diabetes mellitus are?
A
insulins and the oral antidiabetic drugs
25
Several new classes of injectable drugs with unique mechanisms of action have been developed that may be used in addition to insulins or oral antidiabetic drugs to treat resistant diabetes. All of these drugs are referred to as antidiabetic drugs and are aimed at producing a?
normoglycemic or euglycemic (normal blood glucose) state
26
Currently insulin is synthesized in laboratories using recombinant deoxyribonucleic acid technology and is referred to as human insulin. Insulin was originally isolated from cattle and pigs, but bovine and porcine insulins are associated with a higher incidence of allergic reactions and insulin resistance and are no longer available in the U.S. market. Exogenous insulin functions as a?
substitute for the endogenous hormone
27
The pharmacokinetic properties of insulin (onset of action, peak effect, and duration of action) can be altered by?
Making various minor modifications to either the insulin molecule itself or the drug formulation (final product)
- this practice has led to the development of many different insulin preparations, including several combination insulin products that contain more than one type of insulin in the same solution
- further modifications can be accomplished by mixing compatible insulin preparations in the syringe before administration
- thoroughly educate patients regarding how, when, and if they can (or cannot) mix different types of insuline
- some combinations are chemically incompatible and can result in alteration of glycemic effects
28
Exogenous insulin restores?
The patient's ability to metabolize carbohydrates, fats, and proteins; to store glucose in the liver; and to convert glycogen to fat stores
-it does not reverse defects in insulin receptor sensitivity
29
When an insulin pump is used, insulin is administered
| constantly over a?
24-hour period and the patient is then allowed to give bolus injections based on the amount of food ingested.
30
Insulin Indications: All insulin preparations can be used to treat?
both type 1 and type 2 diabetes, but each patient requires careful customization of the dosing regimen for optimal glycemic control.
• Additional therapeutic approaches such as lifestyle modifications (e.g., dietary and exercise habits) are also indicated and, for type 2 diabetes, oral drug therapy as well.
31
Insulin contraindications
- Known drug allergy
- NEVER administer to an already hypoglycemic patient
- blood glucose must ALWAYS be tested prior to administration
32
Insulin adverse effects
Hypoglycemia resulting from excessive insulin dosing can result in brain damage, shock, and possible death. This is the most immediate and serious adverse effect of insulin.
-other effects include: weight gain, lipodystrophy at site of repeated injections, and allergic reactions
33
Insulin interactions
Corticosteroids, estrogen, diuretics, thyroid drugs, nonselective beta blockers
34
Dosages for Insulin lispro (Humalog) (B)
- Rapid acting; human recombinant rapid-acting analgoue
- Usual dosage range: Subcut; 0.5-1 unit/kg/day; doses are individualized to desired glycemic control; rapid-acting insulins are best given at least 15 min before a meal
- may be given per sliding scale or as basal/bolus; may also be given via continuous subcut infusion pump
35
Dosages for insulin regular (Humulin R)
- Short acting, human recombinant short-acting insulin
- Subcut: same dosage as insulin lispro (0.5-1 u/kg/day); subcut doses of regular insulin are best given 30 min before a meal
- regular insulin may also be given per sliding scale or basal/bolus and is the insulin given IV as a continuous infusion
36
Dosages for insulin glargine (Lantus) (C)
- Long acting; human recombinant long-acting insulin analogue
- subcut ONLY: 0.2 units/kg/day given once or twice daily (basal dosing)
37
In emergency situations requiring prompt insulin action what can be given?
Regular insulin can be given IV
- insulin also is available as a U-500 (high alert medication)
- great care must be taken with its use to ensure that the correct dose is administered
- many hospitals do not allow U-500 insulin because of potential for errors
38
Two special patient populations for whom careful attention is required during insulin therapy are?
pediatric patients and pregnant women
- insulin dosages for both are calculated by weight
- usual dosage range: 0.5-1 units/kg/day as total daily dose
39
The rapid-acting insulin lispro is approved for use in?
Children older than 3, however, combination lispro product Humalog 75/25 is not currently approved for use in children younger than 18 years of age
40
Pregnant women require special care with regard to diabetes management. Although most of these mothers will?
Return to a normal glycemic state after pregnancy, they are at risk for developing diabetes again later in life.
41
All currently available oral and injectable antidiabetic drugs are classified as pregnancy category B or C drugs. Oral medications are generally not recommended for pregnant patients because of a?
lack of firm safety data. Insulin therapy is the only currently recommended drug therapy.
- insulin does not generally cross the placenta
- effective glycemic control during pregnancy is essential because infants born to women with gestational diabetes have a twofold to threefold greater risk for congenital anomalies
- incidence of stillbirth directly related to the degree of maternal hyperglycemia
- weight reduction not advised, it can jeopardize fetal nutritional status
- women w/gestational diabetes tend to have babies that weigh more, and these children may have low blood sugar in the postnatal period
- insulin excreted in human milk
42
There are currently four major classes of insulin, as determined by their pharmacokinetic properties:
(1) rapid-acting
(2) short-acting
(3) intermediate-acting
(4) long-acting
- The duration of action ranges from several hours to over 24 hours, depending on the insulin class
43
The insulin dosage regimen for all diabetic patients is highly individualized and may consist of?
One or more classes of insulin administered at either fixed dosages or variable dosages in response to self-measurements of blood glucose level or the number of grams of carbohydrate consumed
44
With the use of insulins what is important to understand for patient safety and for the prevention of adverse effects and complications?
Clarity, color, and appearance
- several insulins are clear, colorless solutions; these include regular insulin, insulin lispro (Humalog), and insulin glargine (Lantus)
- other insulins, such as NPH insulin (insulin isophane), are white opaque (cloudy) solutions
- all insulins are high alert medications
45
Rapid-Acting Insulin: Insulin lispro (Humalog)
- rapid onset of action (15 minutes) & shorter duration of action
- effect of insulin lispro most like that of endogenous insulin produced by pancreas in response to a meal
- after or during a meal, the glucose that is ingested stimulates the pancreas to secrete insulin. This facilitates the uptake of the excess glucose at hepatic insulin receptor sites for storage in the liver as glycogen
- in people w/diabetes, insulin response to meals is often imparied; therefore a rapid-acting insulin product is often used w/in 15 min of mealtime. This corresponds to the time required for the onset of action of these products
- essential for pt's to eat a meal after injection, otherwise profound hypoglycemia results
46
Short-Acting Insulin: Regular Insulin (Humulin R)
- only short acting
- given IV bolus, IV infusion, IM, or subcutaneously
- those routes, especially IV infusion, often used in cases of DKA or coma associated with uncontrolled type 1 diabetes
- differences between these and rapid acting: rapid acting insulins are considered human insulin analogues meaning they are insulin molecules with synthetic alterations to their chemical structures that alter their onset or duration of action. They have a faster onset of action and a shorter time to peak level, but they also have a shorter duration of action than does regular insulin
- regular is made from human insulin sources using recombinant DNA technololgy
47
Intermediate-Acting Insulins: Insulin Isophane suspension (NPH)
- Only available intermediate-acting
- NPH acronym for neutral protamine Hagedorn insulin
- Sterile suspension of zinc insulin crystals and protamine sulfate in buffered water for injection
- suspension appears cloudy or opaque
- slower onset and longer duration of action than regular insulin
- often combined with regular insulin to reduce the number of insulin injections per day
48
Long-Acting insulins: Insulin glargine (Lantus) and insulin detemir (Levemir)
- Insulin detemir (Levemir) classified as intermediate or long acting since given twice daily. In clinical practice it's long acting
- Insulin glargine: clear, colorless solution with a pH 4.0. Once injected into subcutcaneous tissue at physiologic pH, if forms microprecipitates that are slowly absorbed over 24 hrs. It is a DNA-produced insulin analogue and provides a constant level of insulin in the body. This enhances its safety because blood levels do not rise and fall as with other insulins
- Insulin glargin usually dosed once daily but may be dosed every 12 hours depending on the pt's glycemic response
- because insulin glargine provides a more prolonged, consistent blood glucose level, it is sometimes referred to as a basal insulin
- insulin detemir has different MOA from glargine. The two different insulins are NOT considered interchangeable
- duration of action for detemir is dose dependent, so that lower doses require twice-daily dosing and higher doses may be given once daily
49
Fixed-combination insulins: Humulin 70/30, Humalog 50/50
- Each contain 2 different insulins: one intermediate acting type and either one rapid acting (Humalog) or one short acting (Humulin)
- numeric designations indicate percentages of each two components
- each adds up to 100%
- developed to closely simulate varying levels of endogenous insulin that occur normally in nondiabetic people
- developed to simplify dosing process
- allow for twice daily dosing but often result in glycemic control that is not as tight as daily dosing with meals
- pt's who can't afford frequent glucose monitoring or who refuse more than two injections per day may insist on using a combination insulin with twice daily dosing
50
Antidiabetic drugs: Review the appropriate laboratory test results (e.g., FPG level, A1C level) for any abnormalities compared with baseline levels. Assess the prescriber’s order for insulin, so that the correct drug, route, type of insulin (i.e., rapid-acting, short-acting, intermediate-acting, short- and intermediate-acting mixtures, and long-acting), and dosage are implemented correctly. Assess the specific insulin, paying additional attention to the?
specific pharmacokinetics such as onset of action, peak, and duration of action
- if more than one insulin type is prescribed, mixing of insulins may be ordered. Need to know the chemically compatible combinations to avoid glycemic effects
- always perform a second check of the prepared insulin dosage against the medication order with another RN
51
What do you assess PRIOR to administering insulin?
Blood glucose levels to avoid giving the drug to a patient who is already hypoglycemic
52
The 2015 ADA guidelines identify the current key diagnostic criterion for diabetes mellitus as?
Hyperglycemia with a fasting plasma glucose level of higher than 126 mg/dL or a hemoglobin A1C level greater than 6.5%
-Recommends: fasting blood glucose within the range of 70 to 130 mg/dL and/or a hemoglobin A1C less than 7%
53
Allergic reactions are less likely with which insulins?
Recombinant human insulins because their similarity with endogenous insulin; however, allergies may still occur
54
Drugs that work against the effect of insulin include?
Corticosteroids, thyroid drugs, diuretics
55
Drugs that increase the hypoglycemic effects of insulin include?
Alcohol, sulfa antibiotics, and salicylates
56
Assess medication order for all insulins, especially?
U-500 insulin
| -must be administered with great caution
57
S/S of hypoglycemia
Acute onset of confusion, irritability, tremor, and sweating with progression to possible hypothermia and seizures, and blood glucose levels of less than 50 mg/dL
58
S/S of hyperglycemia
Polyuria, polydipsia, polyphagia, glucosuria, weight loss, fatigue, fasting blood glucose level of 126 mg/dL or higher or a nonfasting blood glucose level of 200 mg/dL
59
Assessment is even more critical for a diabetic patient who is also?
Under stress, has an infection of is ill, is pregnant or lactating, or is experiencing trauma or any serious change in health status
60
With treatment, diabetic patients are at risk for?
Hypoglycemia with the potential danger of loss of consciousness; therefore, constantly assess serum glucose levels and neurologic status
61
Which insulins do you NOT shake?
Do not shake NPH (cloudy) and premixed insulin mixtures, but roll between the hands before administering
-rolling helps to avoid air in the syringe and inaccurate dose administration
62
What temperature do you administer insulins?
Room temperature if used within 1 month; otherwise, refrigeration is needed
- refrigeration also recommended in warm or hot climates and with any major changes in environmental temps from cold to hot
- NEVER used expired or discolored insulin
63
Administer insulin subutaneously at a?
90-degree angle unless the patient is emaciated, in which case you may give the insulin at a 45-degree angle
64
Only regular insulin may be administered?
Intravenously and is often used in ICU setting
65
Only use insulin syringes for?
Subcutaneous injections or when drawing up insulin dosage amounts. These syringes are easy to identify because of their orange caps and calibration in units, not milliters
-they have pre-attached needles that are 29 guage and 1/2 inch in length
66
When insulins are mixed (if ordered) which one do you draw first?
The regular or rapid-acting insulin (unmodified and clear) first, followed by withdrawing the intermediate-acting or NPH insulin (modified and cloudy)
- only do this AFTER the appropriate amount of air has been injected into the vials (amount of air=prescribed units)
- inject air into immediate-acting insulin vial FIRST, next inject air into the regular or rapid-or short-acting insulin vial. This will help keep the intermediate-acting insulin from contaminating the rapid-acting insulin vial
- this contamination would lead to a change in the regular, short-acting, unmodified insulin by the NPH, intermediate-acting, modified insulin
- the net effect is an interference of the activity of the regular insulin (no longer considered modified), thus impacting its effect in the patient
67
Make sure to know the patient’s history because type 2 diabetes can be treated with?
oral antidiabetic drugs, most of which require functioning beta cells in the pancreas.
68
With sulfonylureas, it is important to know baseline glucose levels as well as conditions that may predispose the patient to hypoglycemia, such as a?
drop in caloric intake, alcohol use, or advanced age. Assessment of allergic reaction to sulfonamide antibiotics is important.
69
All rapid-acting, short-acting, and long-acting insulin preparations are?
Intermediate-acting insulins are?
Mixtures of short- and intermediate-acting
1) rapid-acting, short-acting, and long-acting insulin preparations are clear solutions
2) Intermediate-acting insulins are cloudy solutions
3) Mixtures of short- and intermediate-acting insulin still look uniformly cloudy
- Vials of insulin should be rolled in the hands instead of shaken when used
70
Oral antidiabetic drugs are usually given?
30 minutes before meals, as ordered
71
When the patient is on nothing by mouth (NPO) status and is taking either an oral antidiabetic drug or insulin, it is crucial to?
follow the prescriber’s orders regarding drug administration
72
Complications associated with diabetes include?
| \
retinopathy, neuropathy, nephropathy, hypertension, cardiovascular disease, and coronary artery disease.
Annual screening with an ophthalmologist specializing in retinopathies is needed in the care of diabetic patients for screening purposes. Because of the renal complications (e.g., nephropathies), annual urinalysis screening is also recommended for diabetic patients. Nursing care must be individualized with patient education focused on the patient’s needs and learning abilities. Present information on all aspects of the disease process, drug therapy, and lifestyle modifications.
73
It is important to know that the rapid-acting insulins (insulin lispro, insulin aspart, and insulin glulisine) have an onset of action of?
About 15 minutes and must be given at least 15 minutes before meals, compared with 30 minutes before meals for regular insulin or a short-acting insulin which has an onset of action of 30 to 60 minutes
74
If lispro insulin (Humalog rapid-acting) is to be mixed with NPH (intermediate-acting) give the combination?
15 minutes before meals
- ALWAYS double-check the prescriber's order for clarification of the dosage and drug as well as of any change in dietary intake, such as a possible increase in carbohydrates and decrease in fat to avoid postprandial hypoglycemia
- a meal high in fat can delay carbohydrate absorption while rapid-acting insulin is already in its peak action
75
The intermediate-acting insulin (NPH) has an onset of action of?
1-2 hours, so serve meals at least 30-45 minutes prior to its administration
76
Many combination products of rapid and short-acting with intermediate-acting insulin are available; give these combination insulins?
15-30 minutes before meals
77
In the hospital setting, be sure that meal trays have arrived on the unit when?
Before giving insulin to avoid time lapses and subsequent hypoglycemic episodes. Also be sure that other forms of allowed foods are available to the patient in case meals are delayed and insulin has already been administered
78
If U-500 insulin is prescribed, a multilayered, multidisciplinary process is recommended to?
Safeguare every step of the medication administration process
- a two-pharmacist order-entry process may be used with the pharmacist hand delivering the dose to the charge nurse and bedside nurse
- use of at least a three-time check of the medication order is also needed at this time
79
Patients may require dosing by a sliding-scale or a basal-bolus method in a hospital setting.
-Sliding scale has been the method for administering?
- Sliding scale: Subcutaneous regular insulin doses adjusted according to serum glucose test results
- sliding scale dosing may be used for hospitalized diabetic patients experiencing drastic changes in serum glucose levels due to physical and/or emotional stress, infections, surgery, acute illness, inactivity, or variable caloric intake, as well as for patients needing intensive insulin therapy or patients receiving total parenteral nutrition (TPN) w/a high glucose concentration
- when this insulin regimen is used, measure blood glucose levels several times per day (every 4hrs, 6hrs, or specified times) to obtain fasting and/or premeal blood glucose values
80
Basal-bolus insulin dosing
- A long-acting insulin (insulin glargine) is used to mimic the basal secretion of a healthy pancreas and constant delivery of an amount of insulin, and then bolus is used (insulin lispro or apart) to control increases in daily blood glucose levels
- bolus insulin divided into meal and correction boluses
- monitor blood glucose levels frequently
81
Adjust dosages, as ordered, to achieve the prescriber's specific fasting blood glucose level for the patient. Using the ADA 2012 guidelines, this would be?
-fasting blood glucose level of 70 to 130 mg/dL and/or hemoglobin A1C less than 7% for the diabetic patient
82
How do store insulin
- Store insulin for current use at room temp
- avoid extreme temps and exposure to sunlight, because insulin's protein structure will be permanently denatured
- extra vials not in use store in refrigerator
- vials being used in high environmental temps need to be stored in refrigerator, but NEVER give cold insulin. Never freeze insulin
- to maintain drug stability, only store insulin for up to 1 month at room temp. or 3 months in refrigerator
- discard unused vials if they have not been used for several weeks
- do NOT use any insulin that does not have the proper clarity or color (clear for regular, cloudy for NPH)
- store prefilled insulin syringes in refrigerator for up to 1 week
- always check expiration dates
83
How do you administer insulin
Administer insulin subcutaneously; however, regular insulin may be given intravenously in special situations (intravenous drip in patient with diabetic ketoacidosis; in postop patients) if ordered
84
Do you shake or roll cloudy drug vials?
Roll cloudy drug vial gently between the hands without shaking to avoid bubble formation in the vial, which may lead to inaccurate dosage withdrawal
-give freshly mixed insulin within 5 minutes of mixing to avoid binding of the solution and subsequent altered activity of the drug
85
Administer insulin at the recommended times, but always with meals or meal trays ready. Give insulin lispro and other rapid-acting insulins approximately?
Regular?
NPH intermediate?
- lispro & other rapid-acting: give 15 minutes before meals
- regular insulin (short-acting): 30 minutes before meals
- NPH intermediate insulin: 30-60 minutes before meals
86
Instruct patients using insulin injections to?
- rotate sites w/in the same general location for 1 week before moving to a new location (all injections for a week in the upper right thigh before moving a little lower on the right thigh) this technique allows for better insulin absorption
- each injection site should be 1/2 to 1 inch away from previous injection site. If this is followed it will be 6 weeks before the patient will have to rotate to a totally new area
87
Sites for subcutaneous insulin injections
- thigh areas (front and back)
- outer areas of upper arm (middle third of upper arm between shoulder and elbow)
- abdominal area using iliac crests as landmarks and using fatty part of abdomen, but NOT within 2 inches of umbilicus or an incision stoma
88
Oral antidiabetic drugs are usually given at least?
30 minutes before meals
89
For any antidiabetic drug or insulin, it is important for both you and the patient to know what to do if symptoms of hypoglycemia occur
-Patient needs to take glucagon; eat glucose tablets or gel, corn syrup, or honey; drink fruit juice or a nondiet soft drink; or eat a small snack such as crackers or half a sandwich
90
If the patient is receiving metformin (oral antidiabetic biguanide), is to undergo diagnostic studies with contrast dye, the prescriber will need to?
Discontinue the drug prior to the procedure and restart if after the tests, but only after reevaluation of renal status
91
During therapy with metformin, the risk for what is possible?
Lactic acidosis is possible, it's important to monitor for and then report hyperventilation, cold and clammy skin, muscle pain, abdominal pain, dizziness, and irregular heartbeat
92
Some of the sulfonylureas are to be taken with?
breakfast
93
the alpha-glucosidase inhibitors are always taken with?
The first bite of each main meal
94
It is critical to the safe and efficient use of oral antidiabetics to be sure that food will be or is being?
Tolerated before the dose is given
-if oral drug is taken and no meal is consumed or consumed at a later time than usual, hypoglycemia may be problematic and result in negative health consequences and even unconsciousness
95
If a patient is on NPO status but is receiving an intravenous solution of dextrose, the prescriber may still order?
Insulin, but always clarify this
- contact prescriber if pt becomes ill and is unable to take oral antidiabetic drug (or insulin)
- pt should wear medical alert bracelet/necklace giving diagnosis, list of meds, emergency contact
96
Macrovascular and microvascular problems are now being recognized to occur at?
Fasting blood glucose levels as low as 126 mg/dL
97
To provide a picture of the patient's adherence to the therapy regimen for the previous several months, what is measured?
The level of A1C is measured. This value reflects how well the patient has been doing with diet and drug therapy
98
With short-acting insulins such as lispro, the onset of action is more rapid than with regular insulin and the duration of action is shorter, so monitor?
Blood glucose levels very closely until the dosage is regulated and blood glucose levels is at the level the prescriber desires
99
Emphasize the importance of A1C monitoring. The American Diabetes Association recommends monitoring at least?
Two times per year for patients with good glycemic control and every quarter for those who are not reaching target values, have changed their therapy, not compliant with regimen
100
Patients with type 2 diabetes have a greater therapeutic response to?
Diet and exercise and glucose level control as compared to patients with type 1
101
Low fat diet
160-300 g of carbohydrates
102
Non-starchy vegetables
spinach, carrots, greens, bok choy, broccoli
103
Starchy foods
Whole-grain breads, high-fiber cereal, oatmeal, cooked beans, peas
104
Advise patient to avoid smoking and alcohol consumption with?
Oral antidiabetic drugs
105
Share with the patient information about situations or conditions that may lead to altered serum glucose levels, such as?
Fever, illness, stress, increased activity/exercise, surgery, and emotional distress
106
Report any?
Yellow discoloration of the skin, dark urine, fever, sore throat, weakness, or unusual bleeding or easy bruising
107
Educate patient about the need to monitor what before exercise?
Blood sugar before and after physical exercise to avoid hypoglycemia and adjusting insulin as needed/orderd/directed
108
Strict foot care for diabetic patients
- daily assessments of the feet and toes to check for sores, lesions, cuts, bruises, ingrown toenails
- foot care needed to enhance circulation and prevent infections
- soaking feet daily or as ordered in lukewarm water, adequate drying of the feet, and then application of moisturizing lotion, and checking the feet and legs for abnormal changes in color (purplish, redish discoloration), cool temperature of feet to touch, swelling of extremities or feet, and the appearance of any drainage
109
Some oral antidiabetic drugs cause?
Photosensitivity. Instruct patient on wearing sunscreen and proper clothing when exposed to sun. Advise against the use of tanning beds
110
Hypoglycemia is an abnormally low blood glucose level
| (generally below 50-70 mg/dL). When the cause is organic and the effects are mild, treatment usually consists of?
dietary modifications to prevent a rebound postprandial hypoglycemic effect.
-higher intake of protein and lower intake of carbohydrates
111
Because the brain needs a constant amount of glucose to function, early symptoms of hypoglycemia include?
Central nervous system manifestations of confusion, irritability, tremor, and sweating
- later symptoms include hypothermia and seizures
- without adequate restoration of normal blood and CNS glucose levels, coma and death will occur
112
Glucose elevating drugs: Oral forms of concentrated glucose are available for patients to use in the event of a?
hypoglycemic crisis. Dosage forms include rapidly dissolving buccal tablets and semisolid gel forms designed for oral use and rapid mucosal absorption. Table sugar, which is sucrose, will not produce as rapid an effect as the glucose products. This is because sucrose is a disaccharide (two molecule) sugar that must first be digested in the body to yield glucose as a monosaccharide (one molecule) by product
113
In the hospital setting or when the patient is unconscious, what glucose elevating drug is used?
Intravenous glucose is an obvious option to treat hypoglycemia. Concentrations of up to 50% dextrose in water (D50W) are most often used for this purpose
114
Glucagon is available as a?
subcutaneous injection to be given when a quick response to severe hypoglycemia is needed. This may
induce vomiting.
-since it may induce vomiting roll an unconscious patient onto the side before injection
-it's useful in the unconscious hypoglycemic patient without established intravenous access
115
Use of an insulin pump (continuous subcutaneous insulin
| infusion) leads to a more?
rapid, consistent absorption of the drug and a reduction in the occurrence of hypoglycemia.
116
The 2013 ADA Guidelines recommend that new-onset type 2 diabetes be treated with both?
lifestyle interventions and the oral biguanide drug metformin, if there are no contraindications to the drug.
-it is NOT used for type 1 diabetes
117
Metformin is currently the only drug classified as a biguanide. It is considered a first-line drug, especially for patients with a body mass index over?
25, and is the most commonly used oral drug for the treatment of type 2 diabetes.
118
Oral antidiabetic: Biguanide Metformin (Glucophage) Mechanism of action
Works by decreasing glucose production by the liver. May also decrease intestinal absorption of glucose and improve insulin receptor sensitivity. This results in increased peripheral glucose uptake and use, and decreased hepatic production of triglycerides and cholesterol
-unlike sulfonylureas, metformin does NOT stimulate insulin secretion and therefore is not associated with weight gain and signifiant hypoglycemia when used alone
119
Oral antidiabetic: Biguanide Metformin (Glucophage) Indications
The ADA guidelines recommend metformin as the initial oral antidiabetic drug for tx of newly diagnosed type 2 diabetes if no contraindications exist
- it may cause moderate weight loss, so it may be useful for the many patients with type 2 diabetes who are overweight or obese
- may be used as monotherapy or in combination with other oral antidiabetic drugs if single dose therapy is unsuccessful. For this reason, it is available in combination products containing either sulfonylureas, thiazolidinediones, or incretin mimetics
- may also be combined with insulin
- used in prediabetic patients
120
Oral antidiabetic: Biguanide Metformin (Glucophage) Contraindications
Metformin is contraindicated in patients with renal disease or renal dysfunction (serum creatinine level higher than 1.5 mg/dL in males or higher than 1.4 mg/dL in females)
- because metformin is primarily excreted by the kidneys, it can accumulate in these individuals, increasing risk for development of lactic acidosis
- other contraindications: alcoholism, metabolic acidosis, hepatic disease, heart failure, and other conditions that predispose to tissue hypoxia and increase the risk for lactic acidosis
121
Oral antidiabetic: Biguanide Metformin (Glucophage) Adverse effects
The most common adverse effects of metformin are gastrointestinal. Metformin can cause abdominal bloating, nausea, cramping, a feeling of fullness, and diarrhea, especially at the start of therapy. These effects are all usually self-limiting & can be lessened by starting with low dosages, titrating up slowly, & taking the medication with food
- less common AEs: metallic taste, hypoglycemia, reduction in vitamin B12 levels after long term use
- lactic acidosis is an rare complication but risk increases with very high blood glucose levels and/or clinical conditions predisposing to hypoxemia
- lactic acidosis is lethal in up to 50% of cases
- Symptoms of lactic acidosis: hyperventilation, cold and clammy skin, muscle pain, abdominal pain, dizziness, irregular heartbeat
122
Oral antidiabetic: Biguanide Metformin (Glucophage) Interactions
Use of metformin with iodinated (iodine-containing) radiologic contrast media has been associated with both acute renal failure and lactic acidosis
-for these reasons, metformin therapy is to be discontinued the day of the test and for at least 48 hours after the patient undergoes any radiologic study that requires the use of such contrast media
123
Oral antidiabetic drugs: Sulfonylureas
| Drug: Glipizide (Glucotrol) Mechanism of action
Bind to specific receptors on beta cells in the pancreas to stimulate the release of insulin
- appear to secondarily decrease the secretion of glucagon
- to be effective the pt must have functioning beta cells in the pancreas
- these drugs work best during the early stages of type 2 diabetes and are not used in type 1
124
Oral antidiabetic: Biguanide Metformin (Glucophage) Indications
- Due to different MOAs, sulfonylureas can be used in conjunction with metformin and thizaolidinediones
- should NOT be used in pt's with advanced diabetes dependent on insulin administration, because the beta cells in such pt's are no longer able to produce insulin
- once insulin started, sulfonylurea medication is stopped
125
Oral antidiabetic: Biguanide Metformin (Glucophage) Contraindications
Hypoglycemia or conditions that can predispose to hypoglycemia, such as reduced caloric intake (e.g. NPO), ethanol use, or advanced age. There is a potential for cross allergy in pt's who are allergic to sulfonamide antibiotics so be aware
126
Oral antidiabetic: Biguanide Metformin (Glucophage) Adverse effects
Most common AE is hypoglycemia, the degree to which depends on the dose, eating habits, and presence of hepatic or renal disease
- another predictable AE is weight gain because of the stimulation of insulin secretion
- other AEs include: skin rash, nausea, epigastric fullness, and heartburn
127
Oral antidiabetic: Biguanide Metformin (Glucophage) interactions
-Hypoglycemic drugs, Cimetidine, Diuretics, corticosteroids, constrast media
128
Sulfonylureas: Glipizide (Glucotrol) onset and duration
Very rapid onset and short duration of action, with no active metabolite
-rapid onset of action allows it to function much like the body normally does in response to meals when greater levels of insulin are required rapidly to deal with increased glucose in the blood
129
When a patient with type 2 diabetes mellitus takes glipizide, it rapidly stimulates?
The pancreas to release insulin. This in turn facilitates the transport of excess glucose from the blood into the cells of the muscles, liver, and adipose tissues
130
Glipizide use is contraindicated in?
- known drug allergy
- type 1 or brittle type 2 diabetes
- NOT contraindicated in pt's with severe renal failure
- works best if given 30 minutes before meals, usually before breakfast. This allows the timing of the insulin secretion induced by the glipizide to correspond with the elevation in blood glucose level induced by the meal in much the same way as endogenous insulin levels are raised in a person without diabetes
- extended release dosage form of glipizide can be given once daily
131
Biguanide: Drug: Metformin (Glucophage)
- only oral biguanide oral antidiabetic drug
- works by inhibiting hepatic glucose production & increasing sensitivity of peripheral tissue to insulin
- due to diff. MOA from sulonylurea it may be given along with these drugs
- contraindicated in pt's w/known hypersensitivity to biguanides, hepatic or renal disease, alcoholism, or cardiopulmonary disease
132
Alpha-Glucosidase Inhibitors MOA
Work by reversibly inhibiting the enzyme alpha-glucosidase that is found in the small intestine
- this enzyme is responsible for hydrolysis of oligosaccharides and disaccharides to glucose. When this enzyme is blocked, glucose absorption is delayed
- timing of administration of the alpha-glucosidase inhibitors is important, and they must be taken with food
- when an alpha-glucosidase inhibitor is taken with a meal, excessive postprandial blood glucose elevation (glucose spike) can be prevented or reduced, making them impractical for directly lowering fasting blood glucose
133
Alpha-Glucosidase Inhibitors Indications
used to treat type 2 diabetes, usually in combination with another oral hypoglycemic drug and especially for high postprandial glucose levels
134
Alpha-Glucosidase Inhibitors contraindications
Because of their adverse GI effects, they are NOT recommended for use in pt's with inflammatory bowel disease, malabsorption syndromes, or intestinal obstruction
135
Alpha-Glucosidase Inhibitors Adverse effects
- These drugs can cause a high incidence of flatulence, diarrhea, and abdominal pain. At high dosages, they may also elevate levels of hepatic enzymes (transaminases)
- unlike sulfonylureas, they do NOT cause hypoglycemia or weight gain
- in rare instance if pt develops hypoglycemia from these drugs, complex carbohydrates cannot be used because alpha-glucosidase is blocked; IV or oral glucose must be administered
136
Alpha-Glucosidase Inhibitors interactions
The bioavailability of digoxin, ranitidine, and propranolol may be reduced when they are taken with alpha-glucosidase inhibitors
137
Make sure to know patients history because type 2 diabetes can be treated with oral antidiabetic drugs, most of which require functioning?
Beta cells in the pancreas. Functioning beta cells are NOT present in type 1 diabetes
138
With biguanides, be aware that older adults or malnourished patients may?
React adversely to this group of drugs
139
Interaction between metformin and the?
Iodine-containing radiologic contrast media used for certain diagnostic purposes (e.g. computed tomography with contrast). This interaction is associated with an increased risk for acute renal failure and lactic acidosis
-if pt is taking metformin, closely assess and monitor for this scenario so that the metformin may be discontinued on the day of the test and for at least 48 hrs afterward
140
With sulfonylureas, it is important to know baseline glucose levels as well as conditions that may predispose the pt to?
Hypoglycemia, such as a drop in caloric intake, alcohol use, or advanced age
141
With alpha-glucosidase inhibitorss assess for contraindications, such as?
inflammatory bowel disease or malabsorption syndromes
-with second generation sulfonylureas, assess the pt's type of diabetes because these drugs are contraindicated in type 1 diabetes
