Introduction to NCLEX^® Review of Antihypertensives

It’s estimated that around 30% of Americans suffer from high blood pressure (HBP) contributing to a rising prevalence of several atherosclerotic diseases (ASCVD) contributing to significant morbidity and mortality rates.

It’s crucial to understand the various types of antihypertensive treatments as they play a substantial role in practice today. This Antihypertensive Pharmacology NCLEX^® Review is designed to provide a practical overview of the different antihypertensive classes, adverse effects, and nursing considerations.

Indications for NCLEX^® Review of Antihypertensives

• Hypertension
  • Confirmed: Systolic blood pressure (SBP) > 130 mmHg or Diastolic blood pressure (DBP) > 80 mmHg
• Chronic kidney disease
• Heart failure
• Post myocardial infarction (MI)
• Post transient ischemic attack (TIA)
• Post hemorrhagic stroke
• Diabetes w/ hypertension

Types of Antihypertensives by Class

ACE inhibitors (ACEi) / Angiotensin receptor blockers (ARBs)

• MOA:
  • ACEi: Competitive inhibitor of angiotensin -converting enzyme preventing the conversion of angiotensin I to angiotensin II → vasodilation → reduced blood pressure
  • ARB: Angiotensin II receptor antagonist blocks the vasoconstrictor effects of angiotensin and aldosterone → vasodilation → reduced blood pressure
• Side Effects:
  • Hypotension
  • Reduction in GFR
  • Hyperkalemia
  • Cough – ACEi > ARB
  • Angioedema – ACEi > ARB
  • Anaphylaxis – ACEi > ARB
• Contraindications:
  • ACEi and ARBs are contraindicated in pregnancy
• Nursing Considerations:
  • Key counseling point:
    • It is important to take these medications every day as they will keep blood pressure under control.
    • If you are pregnant or plan on getting pregnant contact your primary care provider (PCP)
    • There is a chance these medications can cause swelling of the tongue and throat – if you have trouble breathing on this medication contact your PCP immediately.
  • ACE inhibitors are more associated with the “dry cough” side effect and corresponding risk of angioedema and anaphylactoid reactions. In clients who experience these side effects, it is reasonable to try ARBs as an alternative that is less associated with these adverse effects.
  • These are generally first-line treatments for primary and secondary hypertension – additional blood pressure reducing agents may be used in stage 2 hypertension (BP > 140/90)
  • Monitor potassium as these medications can cause hyperkalemia which can lead to arrythmias and cardiac events.
• Common Key Generics (Brands)
  • ACEi:
    • Lisinopril (Zestril, Prinivil)
    • Enalapril (Vasotec)
    • Ramipril (Altace)
    • Captopril (Capoten)
  • ARB:
    • Losartan (Cozaar)
    • Olmesartan (Benicar)
    • Valsartan (Diovan)
    • Candesartan (Atacand)
    • Telmisartan (Micardis)

Diuretics

• MOA:
  • Loop Diuretics: Increases the excretion of sodium (inhibits sodium reabsorption) and other ions (electrolytes) into the urine → pulls water out of the blood into the urine to be excreted → reduced blood pressure
  • Thiazides:  Increases the excretion of sodium (inhibits sodium reabsorption) and other ions in the distal convoluted tubule → increased excretion of water → reduced blood pressure
  • Potassium sparring: Increases sodium excretion through the collecting duct without reducing potassium levels → fluid loss → reduced blood pressure
  • Aldosterone antagonists: Increases sodium excretion through the collecting duct without reducing potassium levels + activity against mineralocorticoid receptor → fluid loss → reduced blood pressure
• Side Effects:
  • Electrolyte imbalances:
    • Loop diuretics, thiazide diuretics: Potassium loss, sodium loss, calcium loss
    • Potassium sparing: Sodium loss, potassium retention
    • Aldosterone antagonists: Sodium loss, potassium retention
  • Fluid management:
    • Many of these medications can cause significant loss of water.
    • Clients with edema or at risk of edema (e.g. heart failure) should monitor weight daily to assess for fluid retention.
  • Dehydration
  • Increased urination
• Precaution:
  • Potassium sparring diuretics and aldosterone antagonists may increase the risk of hyperkalemia – this can lead to arrhythmia which can cause serious cardiac complications. Hyperkalemia is defined as serum potassium > 5.5 mmol/L.
• Nursing Considerations:
  • Key counseling point:
    • You may have to monitor your weight daily to assess for fluid loss.
    • Take these medications as prescribed.
    • These medications can increase the risk of dehydration – monitor for signs and symptoms of dehydration (e.g. dry cracked skin) and hydrate as needed.
    • These medications will make you have to urinate more frequently – take these in the morning to avoid unwanted waking during sleep.
  • Potassium monitoring
• Common Key Generics (Brands)
  • Loop Diuretics:
    • Furosemide
    • Bumetanide
    • Torsemide
    • Ethacrynic acid
  • Thiazide Diuretics:
    • Hydrochlorothiazide (Microzide)
    • Chlorthalidone (Thalitone)
    • Indapamide
    • Metolazone
  • Potassium Sparring:
    • Triamterene
    • Amiloride
  • Aldosterone Antagonists:
    • Spironolactone (Aldactone)
    • Eplerenone

Beta-Blockers

• MOA:
  • Selective and/or nonselective blockade of beta-adrenergic receptors on the heart → decreased heart rate and force of contraction → reduced blood pressure
• Side Effects:
  • Increased risk of falling
  • Decreased energy
    • Fatigue
    • Depression
    • Sexual dysfunction
  • Risk of asthmatic exacerbation in nonselective beta-blockers (e.g. propranolol)
  • Hypoglycemia masking
• Warnings:
  • Risk of asthmatic exacerbation in clients with reactive airway disease – consider cardio-selective betablockers in clients with this comorbidity (e.g. metoprolol, bisoprolol, atenolol, nebivolol)
  • These medications can mask the effect of hypoglycemia – clients with diabetes should be made aware of this potential adverse effect. In clients with uncontrolled diabetes or in those who have frequent hypoglycemic events – increased blood sugar testing is advised.
• Nursing Considerations:
  • Key counseling point:
    • These medications will decrease your energy at first but generally this gets better within a few weeks.
    • This medication increases your risk of serious hypotension – especially when changing positions from sitting to standing too quickly causing orthostatic hypotension. It is important to take it easy when first starting on this medication.
    • If you have diabetes, consider increasing how often you check your blood sugars at first as these medications can mask the effects of hypoglycemia.
  • Clients with reactive airway disease should avoid non-selective beta-blockers (e.g. labetalol, propranolol, carvedilol)
  • Carvedilol, nebivolol, and metoprolol succinate (ER) are preferred in clients for the treatment of heart failure.
  • Metoprolol tartrate is the instant release formulation of metoprolol, and metoprolol succinate is the extended-release (ER) formulation
• Common Key Generics (Brands)
  • Atenolol (Tenormin)
  • Carvedilol (Coreg)
  • Labetalol
  • Metoprolol (Lopressor, Toprol XL)
  • Nebivolol (Bystolic)
  • Propranolol (Inderal LA)

Calcium channel blockers (CCBs)

• MOA:
  • Dihydropyridines: Blocks the influx of calcium into the vascular smooth muscle tissue → vasodilation → reduced blood pressure
  • Non-dihydropyridines: Blocks calcium influx into vascular smooth tissue and myocardial tissue → vasodilation and reduced heart rate + force of contraction → reduced blood pressure
• Side Effects:
  • Edema (swelling in periphery)
  • Headache
  • Reduced heart rate (verapamil, diltiazem)
  • Increased risk of falling (verapamil, diltiazem)
  • Risk of heart block in HFrEF (verapamil, diltiazem)
• Warning:
  • Non-dihydropyridines should be avoided in clients with heart failure with reduced ejection fractions (HFrEF) as this can lead to heart bloack which can be fatal.
• Nursing Considerations:
  • Key counseling point:
    • These medications can cause swelling on your hands and feet – monitor your weight daily to assess for fluid retention.
    • These medications increase the blood flow in your brain which can cause headaches.
    • If on verapamil or diltiazem these medications can slow your heart rate and increase your risk of falling – avoid sudden positional changes (e.g. sitting to standing)
  • Non-dihydropyridines (e.g. verapamil and diltiazem) are generally used for clients who have tachycardia (HR > 100 bpm) and/or arrythmia
• Common Key Generics (Brands)
  • Dihydropyridines
  • Non-dihydropyridines

Key Nursing Tips for Antihypertensives

• Lifestyle interventions are often the first line for clients with stage 1 hypertension without serious risks of having an ASCVD event.
• Encourage lifestyle interventions as they can lead to significant blood pressure reduction
  • Exercise: 150 minutes of moderate-intensity workouts of 75 minutes of vigorous-intensity aerobic activity
  • Weight loss
  • Dietary sodium restriction (< 2 grams/day)
  • Alcohol < 2 drinks/day for men; < 1 drink per day for women
• Tobacco does not chronically elevate blood pressure – it does not cause hypertension but does increase the risk of major cardiovascular events.
• It is not uncommon for clients with hypertension to be on multiple classes of these medications (e.g. ACEi, beta-blocker, diuretics) to adequately control their blood pressure.
• Pregnancy: Many medications are either unsafe or unproven in clients who are pregnant. Below are some potential antihypertensive medications that are proven to be safe and effective in pregnancy.
  • Labetalol
  • Nifedipine
  • Hydralazine
• Many of these drugs can cause serious hypotension which can increase the risk of falling. Use with caution in elderly or in clients with renal failure.

Types of Antihypertensives Conclusion

Hypertension is a highly prevalent disease that millions of Americans suffer from every year. It can increase the risk of having serious cardiovascular events (e.g. strokes, heart attacks). It is imperative to control your client’s hypertension as best as possible to reduce the risk of them suffering from serious ASCVD events – thereby reducing their risk of morbidity and mortality.

For many clients, the first line of therapy for hypertension is simply lifestyle interventions (e.g. weight loss, sodium restriction, exercise) but some clients may require medications to adequately control their blood pressure. For this reason, it is crucial to utilize this NCLEX^® Review of Antihypertensives to further develop your understanding of hypertension and how to treat it.

References

1. Arnett DK, Arnett DK, Blumenthal RS, et al. 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000678. Published March 17, 2019. Accessed April 23, 2020.
2. Townsend R. Major side effects of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
3. Lisinopril: Drug Information. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
4. Losartan: Drug Information. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
5. Brater CD, Ellison D. Mechanism of action of diuretics. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
6. Podrid P. Major side effects of beta blockers. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
7. Bloch M, Basile J. Major side effects and safety of calcium channel blockers. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
8. August P. Management of hypertension in pregnant postpartum women. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
9. Amlodpine: Drug Information. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.
10. Verapamil: Drug Information. In: Post T, ed. UpToDate. Waltham, MA.: UpToDate; 2020. www.uptodate.com. Accessed April 21st, 2020.