Will Olmesartan (Benicar) exacerbate nephrolithiasis (kidney stones)?

From the Guidelines

Benicar (olmesartan) is not known to directly worsen kidney stones, and its use should be considered in the context of overall cardiovascular and renal health, with proper hydration and monitoring of kidney function. This blood pressure medication belongs to the angiotensin II receptor blocker (ARB) class, which generally has a neutral effect on kidney stone formation 1. However, Benicar can affect kidney function in certain individuals, particularly those with pre-existing kidney problems or those taking other medications that impact the kidneys. The medication works by relaxing blood vessels, which can actually improve blood flow to the kidneys in many patients.

Key Considerations

• If you have a history of kidney stones, it's essential to stay well-hydrated while taking Benicar, as proper hydration helps prevent stone formation regardless of medication use 1.
• Some blood pressure medications like thiazide diuretics may actually help prevent certain types of kidney stones, so if kidney stones are a concern, discuss with your doctor whether your current blood pressure medication regimen is optimal 1.
• Any changes in urination patterns, pain, or other symptoms while taking Benicar should be reported to your healthcare provider promptly.

Recommendations

• Increased fluid intake is recommended to prevent recurrent nephrolithiasis, with a goal of at least 2 L of urine per day 1.
• Pharmacologic monotherapy with a thiazide diuretic, citrate, or allopurinol may be considered to prevent recurrent nephrolithiasis in patients with active disease in which increased fluid intake fails to reduce the formation of stones 1.

From the Research

Benicar and Kidney Stones

• Benicar, also known as olmesartan, is an angiotensin II receptor blocker (ARB) used to treat high blood pressure.
• There is no direct evidence that Benicar worsens kidney stones, but its effects on kidney stone risk can be inferred from studies on ARBs and other antihypertensive medications.
• A study published in 2017 2 found that ARBs, including Benicar, were associated with a borderline decreased risk of kidney stones compared to beta-blockers.
• Another study from 2015 3 compared the effects of olmesartan combined with a calcium channel blocker (CCB) or a diuretic on blood pressure variability in elderly hypertensive patients, but did not directly address kidney stone risk.
• However, a 2015 study 4 reported that olmesartan combined with a CCB had a lower incidence of adverse events, including those related to kidney function, compared to olmesartan combined with a diuretic.
• A 2011 study 5 compared the effects of combination therapies, including olmesartan and either a CCB or a thiazide diuretic, in elderly patients with hypertension, and found that the CCB combination had a more favorable effect on kidney function.

Mechanisms and Interactions

• The relationship between Benicar and kidney stones is complex and may involve various mechanisms, including changes in urinary calcium excretion and kidney function.
• Thiazide diuretics, which are often used to treat kidney stones, can increase the risk of kidney stones by increasing urinary calcium excretion, whereas ARBs like Benicar may have a neutral or protective effect on kidney stone risk.
• The choice of antihypertensive medication, including Benicar, should be individualized based on patient characteristics, including kidney function and history of kidney stones.