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NR565 Final Exam Study Guide
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- The first-line medication for type 2 DM is metformin.
- ADA and other professional guidelines inform prescribing decisions.
- Combination injectable therapy should be considered for immediate implementation in patients with an A1C of 10% or higher.
- TZDs, like Actos, can precipitate CHF and should be avoided in patients with heart failure.
- Older adults should be started on lower doses of levothyroxine.
- Radioactive iodine treatment results in lifelong hypothyroidism.
- When treating hypothyroidism, TSH levels should be monitored every 6-8 weeks until the patient achieves a euthyroid state. - Signs and symptoms of hypothyroidism and hyperthyroidism (pp. 418-419) Hypothyroidism: The face is pale, puffy, & expressionless. The skin is cold & dry. The hair is brittle, & hair loss occurs. Heart rate & temperature are lowered. The patient may c/o lethargy, fatigue, & cold intolerance. Mentation may be impaired. Thyroid enlargement may occur if reduced levels of T 3 & T 4 promote excessive release of TSH. Hyperthyroidism: Heartbeat is rapid & strong, & dysrhythmias & angina may develop. The CNS is stimulated, resulting in nervousness, insomnia, rapid thought flow, & rapid speech. Skeletal muscles may weaken & atrophy. Metabolic rate is raised, resulting in increased heat production, increased body temperature, intolerance to heat, & skin that is warm & moist. Increased appetite, but weight loss may occur if caloric intake fails to match the increase in metabolic rate. (Exophthalmos w/Graves’ disease).
- What adjunctive therapy is good to prescribe to control symptoms of hyperthyroidism other than thyroid specific medications? Know drug classes and examples of those drug classes. (pp. 419, 423) Beta-blockers & nonradioactive iodine may be used as adjunctive therapy for hyperthyroidism. Beta-blockers: Suppress tachycardia by blocking beta- receptors on the heart. (“-lol”) Nonradioactive iodine: Inhibits synthesis & release of thyroid hormones. (Lugol Solution = mixture containing 5%
elemental iodine & 10% potassium iodine).
- Monitoring needs and intervals for thyroid medications. (pp. 421, 423)
Hypothyroidism: Levothyroxine (T 4 ) (Brand-name: Levoxyl, Synthroid)
Therapeutic Goal: Resolution of signs & symptoms of hypothyroidism &
restoration of normal lab values for serum TSH & free T 4.
Baseline Data: Obtain serum levels of TSH & free T 4.
Monitoring: Check TSH 6-8 weeks after initiating therapy & after any dosage
change. Check TSH at least once a year after serum TSH is stabilized.
Identifying High-Risk Patients: Use w/caution in those patients with
cardiovascular disease & start w/lower doses in older adult patients.
Evaluating Therapeutic Effects: Look for a reversal of signs of thyroid deficiency
& an absence of signs of thyroid excess. In children, normalization of intellectual function, growth, & development should occur. Monthly measurements of height provide a good index of thyroid sufficiency. Lab tests should indicate normal plasma levels of TSH & T 4. Measure TSH levels at least 1x/year.
Minimizing Adverse Effects: Overdose may cause thyrotoxicosis. Symptoms
include tachycardia, angina, tremor, nervousness, insomnia, sweating, & heat intolerance.
Hyperthyroidism: Methimazole (a thionamide) (Brand-name: Tapazole)
Therapeutic Goal: Methimazole has 4 indications—reduction of thyroid hormone
production in Graves’ disease, control of hyperthyroidism until the effects of radiation on the thyroid become manifest, suppression of thyroid hormone production before subtotal thyroidectomy, & treatment of thyrotoxic crisis.
Baseline Data: Obtain serum levels of TSH, T 3 , & T 4. Check baseline CBC & LFTs
prior to initiation. Monitoring: Check CBC w/differential if signs or symptoms of
infection. Check LFTs if signs or symptoms of liver dysfunction.
Identifying High-Risk Patients: Methimazole should be avoided in the 1 st
trimester of pregnancy & in women who are breastfeeding.
Evaluating Therapeutic Effects: Monitor for weight gain, decreased heart rate, &
other indications that levels of thyroid hormone have declined. Lab tests should indicate a decrease in serum free T 3 & free T 4.
Minimizing Adverse Effects:
Agranulocytosis: Inform patients about early signs of agranulocytosis, including
fever or sore throat. If follow-up blood tests reveal leukopenia, methimazole should be stopped.
Hypothyroidism: Methimazole may cause excessive reductions in thyroid
hormone synthesis. If signs of hypothyroidism develop or if plasma levels of T 3 & T 4 become subnormal, dosage should be reduced.
- Propylthiouracil (PTU) carries a risk for liver toxicity. Although rare, the FDA recommends against using PTU as a first-line treatment due to potential for hepatic toxicity. (p. 422)
infections. If follow-up blood tests reveal leukopenia, this medication should be stopped. It may cause excessive reductions in thyroid hormone synthesis. If signs of hypothyroidism develop or if plasma levels of T 3 & T 4 become subnormal, dosage should be reduced. Radioactive Iodine: Inform patients about symptoms of iodism, including brassy taste, burning sensations in the mouth, & soreness of gums & teeth. Iodine can also cause corrosive injury to the GI tract. Instruct patients to notify the provider if severe abdominal distress develops.
- What drug class can interfere with the assessment and monitoring of diabetes and why? (p. 406) Beta-blockers can delay awareness of & response to hypoglycemia by masking signs that are associated with stimulation of the sympathetic nervous system (tachycardia, palpitations) that hypoglycemia normally causes. Furthermore, because blocking the beta cells impairs glycogenolysis & because glycogenolysis is one means by which the body can respond to & counteract a fall in blood glucose, beta-blockers can make insulin-induced hypoglycemia even worse by preventing the body’s natural counterregulatory response.
- Hgb A1C goals- what are they generally? (p. 400) Review goal guidelines for different age groups within the ADA DM Guidelines linked in the Endocrine Case Studies and on your Student Lesson Plan. The general goal is to keep the Hgb A1c less than 7%. A less stringent goal of less than 8% may be appropriate for some patients, such as those with a history of severe hypoglycemia, limited life expectancy, or advanced microvascular or macrovascular complications. Hgb A1c should be measured every 3 months until the value drops to 7% & at least every 6 months thereafter. (A value of 6.5% or greater is considered diagnostic of diabetes.) Older Adults: Older adults who are otherwise healthy with few coexisting chronic illnesses & intact cognitive function & functional status should have lower glycemic goals (such as A1c <7.5%), while those with multiple coexisting chronic illnesses, cognitive impairment, or functional dependence should have less stringent glycemic goals (such as A1c <8.0-8.5%). Children & Adolescents: A reasonable A1c target for most children & adolescents with type 2 diabetes treated with oral agents alone is <7%. More stringent A1c targets (such as <6.5%) may be appropriate for selected individual patients if they can be achieved without significant hypoglycemia or other adverse effects of treatment. Appropriate patients might include those with short duration of diabetes & lesser degrees of beta-cell dysfunction & patients treated with lifestyle or metformin only who achieve significant weight improvement.
- Review diagnostic criteria and process for DM (p. 398) Criteria for the Diagnosis of Diabetes Mellitus Fasting plasma glucose? 126 mg/dL (no caloric intake for at least 8 hours) OR
Random plasma glucose? 200 mg/dL plus symptoms of diabetes
(polyuria, polydipsia, & unexplained weight loss) OR Oral glucose tolerance test (OGTT): 2-hour plasma glucose? 200 mg/dL (plasma glucose content is measured 2 hours after ingesting the equivalent of 75 grams of anhydrous glucose dissolved in water) OR Hemoglobin A1C 6.5% or higher
- Know examples, mechanism of action, and contraindications for DM drug
classes. (pp. 407-415) Biguanides: Metformin ( Glucophage, Fortamet,
Glumetza, Riomet)
THE DRUG OF CHOICE FOR INITIAL THERAPY IN MOST PATIENTS W/TYPE 2 DM
MOA: Inhibits glucose production in the liver, slightly reduces glucose
absorption in the gut, & sensitizes insulin receptors in target tissues (fat & skeletal muscle) & thereby increases glucose
monitoring weight and BMI is needed. Regular LFTs monitoring is also recommended due to the action of the drug in the liver.
BLACK BOX WARNING: Pioglitazone is associated with heart failure (HF)
secondary to renal retention of fluid. If HF is diagnosed, pioglitazone should be discontinued or used in reduced dosage.
Dipeptidyl Peptidase-4 (DPP-4) Inhibitors: Alogliptin ( Nesina),
Linagliptin ( Tradjenta), Saxagliptin ( Onglyza), Sitagliptin ( Januvia)
MOA: Enhances actions of incretin hormones to stimulate glucose
dependent insulin & suppresses glucagon release.
Side effects: Pancreatitis, disabling joint pain, UTIs, URIs
Contraindications: No known clinically relevant drug interactions & no
contraindications, including pregnancy. Use with caution in patient that have a
history of pancreatitis. (May cause severe & disabling joint pain that can occur
at any point during treatment, angioedema, & acute pancreatitis.)
Sodium-Glucose Cotransporter 2 (SGLT-2) Inhibitors: Canagliflozin
( Invokana), Dapagliflozin ( Farxiga), Empagliflozin ( Jardiance)
MOA: Reduces the reabsorption of glucose by the kidneys in the
proximal nephron, increasing urinary excretion of glucose.
Side effects: glucosuria, UTI, vag yeast infection, hyperkalemia,
dehydration, increased risk amputations
Contraindications: Use with caution in patients prone to vulvovaginal & urinary
tract infections. (Due to SGLT2 actions on the kidneys, there is a risk for
volume depletion and hypotension and can lead to diabetic ketoacidosis.
SGLT2 drugs may cause weight loss as well. Creatinine should be monitored
as well as urinalysis. With an increase of glucose in the urine, patients taking
these medications are at higher risk for UTIs and pyelonephritis. There is also
an increased risk for the need for leg and foot amputations in patients on
SGLT2 drugs.)
Glucagon-like Peptide-1 (GLP-1) Receptor Agonists (AKA Incretin
Mimetics): Exenatide ( ByeGa), Liraglutide ( Victoza), Dulaglutide
( Trulicity), Lixisenatide ( Adlyxin)
GIVEN BY SQ INJECTION
MOA: Lowers glucose by slowing gastric emptying, inhibits glucagon,
suppresses appetite, & stimulates glucose-dependent release of insulin.
Side effects: Pancreatitis
Contraindications: Contraindicated in patients with a personal or family
history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2. Avoid use in patient with renal dysfunction or who have undergone renal transplant. Should be used with caution in pregnancy; benefits should clearly outweigh risks. May cause pancreatitis; therefore, monitoring of amylase and lipase is warranted, & use with caution in patients with a history of pancreatitis.
- Be able to calculate the total daily dose of insulin based on weight. Calculate with the lowest possible dose unless otherwise specified. (p. 405) Initial dosages: Type 1 DM: 0.5-0.6 units/kg/day
ADA’s DM Treatment Algorithm
Step 1 : At diagnosis, initiate lifestyle changes plus metformin.
Step 2 : Continue step 1 & add a 2 nd^ drug (TZD, DPP-4, SGLT-2, or
GLP-1). A sulfonylurea or basal insulin should be considered if patient doesn’t achieve goal with these drugs.
Step 3 : 3-drug combo, including metformin.
Step 4 : 3 drug therapy that includes basal insulin fails to reach
goals after 3-6 months, proceed to combination injectable insulin.
In most patients, treatment is recommended to begin at Step 1 &
progress to Steps 2, 3, & 4 as necessary. For patients who have
an A1c of? 9% at the time of diagnosis, dual therapy is
recommended (i.e., start at Step 2). For patients who have an A1c
? 10%, a fasting blood glucose? 300, or are markedly symptomatic, injectable therapy should be considered immediately. Increase insulin: High carb diet, infection, stress, obesity, adolescent growth spurt, & pregnancy after 1st^ trimester. Decrease insulin: Missed meal or low carb diet, exercise, & 1 st^ trimester of pregnancy.
- Be familiar with frequency of Hgb A1C monitoring timeline. (p.
*Hgb A1c provides an index of average glucose levels over the prior 2-
months. A1c should be measured every 3 months until the value drops to 7% & at least every 6 months thereafter.
- Know when to start insulin. *Start on all type 1 DM patients. *Drug of choice for gestational diabetes. The ADA recommends initiation of basal insulin at 10 units/day or 0.1–0.2 units/kg/day, adjusted by 10–15% or 2–4 units once or twice weekly to reach a target fasting plasma glucose (FPG) in patients whose A1c remains uncontrolled after >3 months of triple
combination therapy ( Step 3) or patients with an A1c >10%. With a
fasting glucose level >300 or markedly symptomatic, start insulin therapy right away.
- Know how insulin is mixed (combination and amount) when Total Daily Dose (TDD) is calculated. (p. 404) Mixing should be done only with insulins of proven compatibility. Of
the 3 longer-acting insulins in current use, only NPH insulin is
appropriate for mixing with short-acting insulins (regular, lispro,
aspart, & glulisine insulins). When a mixture is prepared, the short- acting insulin should be drawn into the syringe first to avoid contaminating the stock vial of the short acting insulin with NPH insulin.
- Know what type of insulin and how much is needed according to carbohydrate intake.
- LABAs are not recommended for use as rescue treatments in asthma.
- SABAs (albuterol and levalbuterol) are recommended for rescue use in asthma.
- A stepwise approach is recommended for managing asthma.
- All asthma patients should have a SABA (albuterol) available for emergency use.
- Chronic use of high-dose inhaled steroids may cause osteoporosis, growth failure in children, glaucoma, cataracts, immune suppression, and hypothalamic-pituitary-adrenal suppression.
- SABA therapy is evaluated through breath sounds assessment.
- Exercise-induced bronchospasm and the routine use of SABAs are markers of inadequate asthma control.
- Be familiar with step therapy and asthma treatment so you know when which medication would be appropriate for which type of asthma. (pp. 576-577) -Know the description of each type or degree of asthma. (pp. 574-575) Chronic Asthma has 4 Classes of Increasing
Severity: ( based on Impairment & Risk) IntermiGent:
INHALED: Beclomethasone dipropionate ( QVAR), Budesonide
( Pulmicort), Fluticasone propionate ( Flovent HFA & Flovent Diskus)
ORAL: Methylprednisolone ( Medrol & Medrol Dose-Pak), Prednisolone
( Orapred), Prednisone ( Deltasone)
MOA: Decrease respiratory symptoms by suppressing inflammation, leading
to reduced bronchial hyperreactivity & decreased airway mucus production.
Contraindications: Inhaled glucocorticoids are contraindicated for
patients w/persistently positive sputum cultures for Candida albicans.
Leukotriene Receptor Antagonists (LTRA): Montelukast ( Singulair),
Zafirlukast ( Accolate), Zileuton ( Zyflo)
*USED AS 2 ND^ LINE THERAPY WHEN GLUCOCORTICOID CAN’T BE USED &
AS ADD-ON THERAPY WHEN GLUCOCORTICOID ALONE IS INADEQUATE*
MOA: Decrease bronchoconstriction & inflammatory responses such as
edema & mucus secretion through suppressing the effects of leukotrienes (compounds that promote smooth muscle constriction, blood vessel permeability, & inflammatory responses through direct action as well as through recruitment of eosinophils & other inflammatory cells).
Contraindications: Montelukast has a BLACK BOX WARNING as this drug
is known to cause serious neuropsychiatric effects such as agitation, aggression, insomnia, depression, anxiety, and suicidal ideation. A thorough health history and patient education are necessary before prescribing this medication. These symptoms can occur at any time during treatment. If these symptoms occur, the drug should be stopped immediately.
Mast Cell Stabilizer: Cromolyn ( Nasalcrom)
*RARELY USED, INDICATED FOR THE TREATMENT OF EXERCISE-INDUCED
ASTHMA*
MOA: Act by stabilizing the cell membranes of mast cells to prevent the
release of histamine, an inflammatory mediator. Also inhibits eosinophils, macrophages, & other inflammatory cells.
Contraindications: Allergy to cromolyn. Otherwise, considered the safest of
all anti-asthma meds.
Monoclonal Antibodies: Omalizumab ( Zolair)
ANTI-IgE ANTIBODY, 2 ND^ LINE AGENT INDICTATED ONLY FOR ALLERGY- RELATED ASTHMA
MOA: Forms complexes w/free IgE in the body & thereby reduces the
amount of IgE available to bind with its receptors on mast cells.
Contraindications: BLACK BOX WARNING—Omalizumab carries a risk
for anaphylaxis that may occur at any time during the course of treatment. Patients should be notified of signs or symptoms that necessitate seeking medical care. Patients should be routinely monitored after administration in health care settings (drug is given
INHALED (SHORT ACTING) aka SABA: Albuterol ( ProAir HFA, Proventil
HFA, Ventolin HFA), Levalbuterol ( Xopenex)
INHALED (LONG ACTING) aka LABA: Arformoterol ( Brovana),
Formoterol ( Foradil Aerolizer), Indacaterol ( Arcapta Neohaler),
Olodaterol ( Striverdi Respimat), Salmeterol ( Serevent Diskus) ORAL:
Albuterol ( VoSpire ER), Terbutaline ( generic only)
MOA: Activate beta-adrenergics receptors in smooth muscle of the lung,
thereby promoting bronchodilation & relieving bronchospasm.
Contraindications: Systemic (oral, parenteral) beta-agonists are
contraindicated for patients with tachydysrhythmias or tachycardia associated with digitalis toxicity. Use with caution in patients with diabetes, hyperthyroidism, organic heart disease, HTN, or angina pectoris.
Adverse effects: tachyarrhythmias, tremors, dizziness
BLACK BOX WARNING: All long-acting beta-agonists (LABAs) carry a
risk for asthma-related deaths. To decrease this risk, the use of LABAs as monotherapy is contraindicated. LABAs should only be prescribed as a component of long-term therapy with medications such as inhaled glucocorticoids.
Methylxanthines: Aminophylline ( generic only), Theophylline ( Zolair)
GIVEN ORALLY
MOA: Produces bronchodilation by relaxing smooth muscle of the bronchi.
Contraindications: These drugs are contraindicated for patients with
untreated seizure disorders or peptic ulcer disease. Use with caution in patients with heart disease (can exacerbate dysrhythmias), liver dysfunction (increased risk for toxicity), peptic ulcer disease (can exacerbate condition), or seizure disorders (can exacerbate seizures). Methylxanthines: Approved for child of all ages, including neonates. Pregnant women: associated with adverse effects in some animal studies. Breastfeeding: warns against breastfeeding if mom may have toxic levels. Older adults: high risk for toxicity.
Anticholinergics (muscarinic antagonist): SAMA-Ipratropium ( Atrovent
HFA), LAMA-Tiotropium ( Spiriva) INHALED
MOA: Works by blocking acetylcholine, a neurotransmitter, to prevent
bronchial constriction & narrowing of the airways, which indirectly facilitates bronchodilation.
Contraindications: Contraindicated in patients with acute narrow-angle
glaucoma or an enlarged prostate. (These contraindications are related
to the action of acetylcholine. Acetylcholine is the primary
neurotransmiGer of the parasympathetic nervous system; when
acetylcholine is blocked, so are actions of the parasympathetic nervous
system which results in identified side effects of the drug.)
Anti-inflammatory/Bronchodilator Combinations:
Budesonide/formoterol ( Symbicort), Fluticasone/salmeterol ( Advair Diskus, Advair HFA)
