What is the relationship between Angiotensin Receptor Blockers (ARBs) and hyponatremia?

From the Guidelines

Angiotensin II receptor blockers (ARBs) can cause hyponatremia, and if a patient on ARBs develops hyponatremia, the medication should be evaluated as a potential cause, especially if the hyponatremia developed after starting the medication, as stated in the 2017 ACC/AHA/HFSA focused update of the 2013 ACCF/AHA guideline for the management of heart failure 1. The development of hyponatremia in patients on ARBs is a significant concern, as it can lead to increased morbidity and mortality. According to the 2008 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure, volume depletion and hyponatremia from excessive diuresis may increase the risk of hypotension and renal dysfunction with ACEI/ARB therapy 1.

Key Points to Consider

• ARBs like losartan, valsartan, and candesartan can lead to hyponatremia through several mechanisms, including blocking the effects of angiotensin II, which normally stimulates thirst and the release of antidiuretic hormone (ADH) 1.
• Management includes assessing the severity of hyponatremia, considering discontinuation or dose reduction of the ARB, restricting fluid intake if appropriate, and possibly switching to an alternative antihypertensive medication class.
• Patients at higher risk include the elderly, those on diuretics, and individuals with heart failure, cirrhosis, or chronic kidney disease, as mentioned in the 2005 ACC/AHA guideline update for the diagnosis and management of chronic heart failure in the adult 1.
• Regular monitoring of serum sodium levels is recommended when starting ARB therapy, especially in high-risk patients.

Recommendations for Clinical Practice

• Monitor serum sodium levels regularly in patients on ARBs, especially in high-risk patients.
• Evaluate the medication as a potential cause of hyponatremia if it develops after starting ARB therapy.
• Consider discontinuation or dose reduction of the ARB, restricting fluid intake if appropriate, and possibly switching to an alternative antihypertensive medication class if hyponatremia occurs.

From the Research

ARBS and Hyponatremia

• The relationship between Angiotensin Receptor Blockers (ARBs) and hyponatremia is not directly addressed in the provided studies.
• However, the studies discuss the use of ARBs in the management of hypertension and heart failure, which can be related to hyponatremia.
• According to 2, hyponatremia in heart failure patients is a multifactorial process, and the therapeutic approach to treatment has traditionally relied on improving cardiac function and limiting fluid intake.
• The use of ARBs in heart failure is discussed in 3, which states that ARBs can reduce morbidity and mortality, as well as improve quality of life, when added to conventional treatment for patients with heart failure.
• Additionally, 4 mentions that ARBs are well tolerated and can be used in combination with other antihypertensive medications, including diuretics, which can help manage hyponatremia.
• The management of hyponatremia is also discussed in 2, which mentions the use of hypertonic saline, loop diuretics, and vasopressin receptor antagonists, such as conivaptan, lixivaptan, and tolvaptan, as treatment options.
• However, there is no direct evidence in the provided studies to suggest a link between ARBs and the development or treatment of hyponatremia.