Lisinopril is a commonly prescribed medication primarily used to manage high blood pressure, also known as hypertension. It is also approved for treating heart failure and improving outcomes after a heart attack. A frequent concern among individuals taking this medication involves its potential impact on kidney health. This article explores how lisinopril interacts with kidney function, the circumstances that might increase the risk of kidney issues, and how kidney health is monitored during treatment.
How Lisinopril Interacts with Kidney Function
Lisinopril belongs to a class of drugs known as Angiotensin-Converting Enzyme (ACE) inhibitors. These medications work by blocking the action of an enzyme responsible for converting angiotensin I into angiotensin II. Angiotensin II narrows blood vessels and increases blood pressure. Inhibiting its production relaxes and widens blood vessels, lowering blood pressure.
This mechanism affects the kidneys. Angiotensin II normally constricts the efferent arterioles, which are small blood vessels that carry blood away from the glomeruli, the kidney’s filtering units. By reducing angiotensin II, lisinopril causes these efferent arterioles to relax and dilate. This dilation lowers the pressure within the glomeruli, which can be beneficial for kidney protection in certain conditions, such as reducing protein in the urine (proteinuria) in patients with diabetic kidney disease.
Despite these protective benefits, this same mechanism can sometimes lead to a temporary decrease in the kidney’s filtration rate. While often temporary and reversible, this change in filtration can be more pronounced if the kidney’s blood flow is already compromised.
Assessing the Risk of Kidney Damage
For most individuals with healthy kidneys, lisinopril does not cause permanent kidney damage. A common effect is a transient increase in blood creatinine levels, a waste product indicating kidney function. This slight, typically reversible elevation does not indicate lasting damage, but reflects the medication’s effect on kidney blood flow.
However, specific situations and pre-existing conditions can increase the risk of more significant kidney issues. Individuals with pre-existing or compromised kidney function may experience a more noticeable decline in filtration. Renal artery stenosis, a narrowing of kidney arteries, is another condition where lisinopril can acutely reduce kidney function, especially if both arteries are narrowed.
Other risk factors include severe heart failure, as the kidneys may already be under stress. Dehydration, often caused by inadequate fluid intake, vomiting, or diarrhea, can also make kidneys more susceptible to a decline in function. Additionally, concurrent use of other medications that affect kidney function, such as nonsteroidal anti-inflammatory drugs (NSAIDs) or certain diuretics, can increase the risk. Acute kidney injury (AKI), if it occurs, is frequently reversible if identified and managed promptly, often by adjusting or discontinuing the medication.
Monitoring Kidney Health While on Lisinopril
Regular monitoring of kidney health is important during lisinopril treatment. Healthcare providers typically recommend blood tests before starting the medication and periodically throughout treatment. These tests include blood urea nitrogen (BUN), creatinine, and estimated glomerular filtration rate (eGFR), which indicate kidney filtering efficiency. Potassium levels are also monitored, as lisinopril can increase blood potassium.
Patients should report symptoms indicating a kidney issue to their healthcare provider. Symptoms include decreased urine output, swelling in the legs or ankles, and unusual fatigue. Nausea can also be a symptom.
Communicate any concerns or new symptoms to a healthcare provider promptly. Never stop or adjust lisinopril dosage without consulting a doctor. Staying well-hydrated and managing other underlying conditions, like high blood pressure or diabetes, also supports kidney health during lisinopril treatment.