Skip to ContentGo to accessibility pageKeyboard shortcuts menu
OpenStax Logo
Pharmacology for Nurses

18.3 Angiotensin II Receptor Blockers (ARBs)

Pharmacology for Nurses18.3 Angiotensin II Receptor Blockers (ARBs)

Learning Outcomes

By the end of this section, you should be able to:

  • 18.3.1 Identify the characteristics of the angiotensin II receptor blocker drugs used to treat hypertension.
  • 18.3.2 Explain the indications, actions, adverse reactions, and interactions of the angiotensin II receptor blocker drugs used to treat hypertension.
  • 18.3.3 Describe nursing implications of angiotensin II receptor blocker drugs used to treat hypertension.
  • 18.3.4 Explain the client education related to angiotensin II receptor blocker drugs used to treat hypertension.

Introduction and Use

Angiotensin II receptor blockers (ARBs) are a classification of drug that binds to and inhibits angiotensin II type I receptors. Renin secretion catalyzes the conversion of angiotensinogen to angiotensin in the liver where it is then converted to angiotensin II by the angiotensin-converting enzyme.

ARBs resemble ACE inhibitors in how they affect blood pressure and the cardiovascular system. However, there are three notable differences: ARBs are less likely than ACE inhibitors to cause a chronic cough (Carter, 2022); the risk of angioedema is decreased with ARBs as compared with ACE inhibitors; and ARBs have been shown to be effective in the treatment of chronic kidney disease and heart failure.

Table 18.5 lists common ARBs and typical routes and dosing for adult clients.

Drug Routes and Dosage Ranges
Candesartan
(Atacand)
16 mg orally daily; maximum dose 32 mg daily in 1–2 divided doses.
Losartan
(Cozaar)
25–100 mg orally daily in 1–2 divided doses.
Telmisartan
(Micardis)
40 mg orally daily initially; maximum dose 80 mg daily.
Valsartan
(Diovan)
80–320 mg orally once daily.
Table 18.5 Drug Emphasis Table: ARBs (source: https://dailymed.nlm.nih.gov/dailymed/)

Adverse Effects and Contraindications

Adverse effects of ARBs include dizziness, muscle cramps, weakness, heartburn, diarrhea, leg swelling, headaches, and weight loss. Serious adverse effects include angioedema, hypotension, hepatic impairment, and hyperkalemia.

Special Considerations

ARBs

The renin-angiotensin system has been associated with increased risk of mood disorders. The use of ARBs may be associated with an increased risk of suicide compared with other antihypertensive therapies (Sanches & Teixeira, 2021). Hypertensive clients with low renin (sometimes seen more often in Black clients) demonstrate a lower response to ARB monotherapy. Concomitant therapy may be required to increase response to antihypertensive therapies. Older adults (65 years and older) and clients with hepatic impairment should start on a low initial dose because ARBs are metabolized by the liver.

(Source: Colvin et al., 2020)

ARBs should not be taken during pregnancy. Clients with hepatic impairment should use ARBs cautiously. Clients with a previous hypersensitivity reaction or angioedema to an ARB should not be prescribed this classification of drug. Clients with a history of mood disturbances or who are at risk for mood disturbances should be monitored closely for suicidal ideation.

Safety Alert

ARBs

ARBs can have teratogenic effects (causing harm to the embryo or fetus), so clients should avoid being pregnant while taking an ARB.

Table 18.6 is a drug prototype table for ARBs featuring valsartan. It lists drug class, mechanism of action, adult dosage, indications, therapeutic effects, drug and food interactions, adverse effects, and contraindications.

Drug Class
Angiotensin II receptor blocker (ARB)

Mechanism of Action
Blocks the binding of angiotensin II to
the angiotensin I receptor, thereby decreasing
vasoconstriction and lowering blood pressure
Drug Dosage
80–320 mg orally daily.
Indications
To control hypertension
In the treatment of heart failure

Therapeutic Effects
Lowers blood pressure
Increases blood supply and oxygen
to the heart
Drug Interactions
Aliskiren
Spironolactone
Triamterene
Amiloride
NSAIDs, including selective COX-2 inhibitors
ACE inhibitors
Lithium
Potassium supplements
Salt substitutes

Food Interactions
Alcohol
Tobacco
Adverse Effects
Hematuria
Dizziness
Syncope
Increased thirst
Decreased urinary output
Irregular heartbeat
Angioedema
Hyperkalemia
Orthostatic hypotension
Contraindications
Hypersensitivity
Concomitant use with aliskiren in clients with diabetes mellitus
Pregnancy

Caution:
Hepatic impairment
Renal impairment
Hypotension
Hypovolemia
Hyperkalemia
Breastfeeding
Table 18.6 Drug Prototype Table: Valsartan (source: https://dailymed.nlm.nih.gov/dailymed/)

Nursing Implications

The nurse should do the following for clients who are taking ARBs:

  • Monitor the client’s blood pressure as prescribed.
  • Monitor the client for interactions because many medications and herbal supplements interact with ARBs.
  • Monitor the client for adverse effects, including electrolyte imbalances and alterations in liver and renal function.
  • Provide client teaching regarding the drug and when to call the health care provider. See below for client teaching guidelines.

Client Teaching Guidelines

The client taking an ARB should:

  • Avoid foods high in potassium and salt substitutes (because these are high in potassium).
  • Report side effects such as low blood pressure, cough, heart palpitations, fever, chills, sore throat, swelling of lips or face, shortness of breath, or difficulty breathing to the health care provider.
  • Notify their health care provider if they experience abdominal pain, joint or muscle aches, muscle weakness, change in the amount of urine produced, or trouble breathing.
  • Notify their health care provider if pregnant, planning on getting pregnant, or breastfeeding before starting an ARB.

FDA Black Box Warning

ARBs

ARBs have the potential to harm or even kill a fetus if a client takes these drugs while pregnant.

Citation/Attribution

This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax's permission.

Want to cite, share, or modify this book? This book uses the Creative Commons Attribution License and you must attribute OpenStax.

Attribution information
  • If you are redistributing all or part of this book in a print format, then you must include on every physical page the following attribution:
    Access for free at https://openstax.org/books/pharmacology/pages/1-introduction
  • If you are redistributing all or part of this book in a digital format, then you must include on every digital page view the following attribution:
    Access for free at https://openstax.org/books/pharmacology/pages/1-introduction
Citation information

© May 15, 2024 OpenStax. Textbook content produced by OpenStax is licensed under a Creative Commons Attribution License . The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.