The pharmacist’s role in kidney health

In this article:

• Prevalence of kidney disease
• Medication management
• Beware the triple whammy
• Counseling patients
• Bottom line

In this article

• Prevalence of kidney disease
• Medication management
• Beware the triple whammy
• Counseling patients
• Bottom line

Kidney disease is a progressive condition that many patients live with, sometimes without even knowing they have it. As vital organs, the kidneys are key points for monitoring dosages, drug interactions, and potential nephrotoxic effects. 

Pharmacists can be valuable in advising patients on kidney health, especially by adjusting medications and flagging harmful drug interactions. Picking up prescriptions at the pharmacy may be one of the few times that patients get the nudge they need to get their kidney health checked. 

The prevalence of kidney disease in the U.S.

Chronic kidney disease (CKD) is one of the most common conditions in the U.S., affecting almost 36 million Americans. It’s often associated with other chronic conditions, such as diabetes and high blood pressure, which can make the risk even more severe. 

What’s more, almost 90% of patients with CKD don’t even know they have it. That’s because many patients don’t experience any significant symptoms in the early stages. As a patient’s estimated glomerular filtration rate (eGFR) worsens, more severe symptoms may appear, especially after kidney damage has already become apparent. 

Medication management in kidney disease

Most, if not all, prescription medication labels discuss whether active drug ingredients are metabolized by the kidneys. After all, the kidneys are responsible for filtering and clearing many medications from the body. Reduced kidney function could mean drug accumulation and toxicity, which could lead to severe side effects.

Dosage adjustments based on kidney function

Pharmacists are in a position to monitor correct dosages based on kidney function, especially in older adults or those with CKD. Some medications require lower doses and longer dosing intervals, or they should be avoided altogether if eGFR is below a certain threshold. 

Medications that need special attention include the following:

• Metformin: This common Type 2 diabetes drug is mainly cleared through the kidneys. It should be used with caution when eGFR falls below 45 mL/min/1.73 m² and is contraindicated below 30 mL/min/1.73 m² due to the risk of lactic acidosis.
• NSAIDs: Nonsteroidal anti-inflammatory drugs like ibuprofen and naproxen may affect blood flow to the kidneys and worsen renal function, especially at high or prolonged doses. They should generally be avoided in CKD due to the risk of acute kidney injury (AKI). 
• Certain antibiotics: Aminoglycosides like gentamicin and tobramycin can worsen kidney damage or cause kidney injury. These antibiotics can cause direct nephrotoxicity, warranting their avoidance altogether. Antibiotics such as fluoroquinolones may be prescribed with caution and at lower doses in patients with CKD.
• DOACs: Direct oral anticoagulants like rivaroxaban, dabigatran, and apixaban are all excreted through the kidneys to some extent. Therefore, they often need to be monitored and adjusted based on kidney function. Dabigatran has the highest renal clearance among this drug class.

Since kidney function can vary with a patient’s age and overall condition, pharmacists and healthcare providers need to be vigilant for potential renal effects. Otherwise, patients could expect worsened adverse effects.

Beware of the “triple whammy”

For many patients taking several medications, it’s especially important to watch for the triple whammy, a classic dangerous drug combo that can harm the kidneys. Consisting of an ACE inhibitor or ARB, a diuretic, and an NSAID, this combination can decrease kidney perfusion and increase the risk of an AKI. 

Patients on an ACE inhibitor or ARB and a diuretic might stop by the pharmacy to pick up an NSAID as an everyday pain reliever without knowing the potential risk. Or, they might be on a regular NSAID for arthritis and receive a new prescription for an ACE inhibitor-diuretic combo. Seeing this combination could be a cue for a pharmacist to intervene, especially given the higher risk at the start of treatment.

Early detection and screening in pharmacies

Even in otherwise healthy adults, kidney function can decline with age. After age 40, eGFR declines at approximately 1 mL/min per year. Although serum creatinine levels may appear normal in patients in their 70s or 80s, kidney function could still be reduced, since older adults have lower muscle mass. 

Therefore, it’s important not to rely solely on creatinine and instead calculate eGFR. Pharmacists who have access to patient labs during medication therapy management should always consider the patient’s age and weight when assessing kidney function. 

Risk factors to look out for

Certain patients may have other conditions that could increase their risk of CKD. It may be helpful to keep kidney function in mind when caring for patients with a personal or family history of the following:

• Type 2 diabetes
• Hypertension
• Coronary artery disease
• Obesity
• Gout
• HIV

Patients taking medications for these conditions may be candidates for a conversation about kidney disease. For example, a patient who’s been on lisinopril for years and never mentioned kidney disease may have overlooked discussing kidney function with their healthcare provider. As a pharmacist, you can prompt them to bring this up at their next doctor’s visit. 

Opportunities in point-of-care testing

With pharmacies offering point-of-care testing services such as blood pressure and blood sugar checks, pharmacists may be able to counsel patients about potential kidney dysfunction. High blood pressure or blood sugar levels may suggest a need for follow-up labs, including serum creatinine, eGFR, and urine albumin-to-creatinine ratio (uACR).

Hospital and clinical pharmacists often have direct access to a patient’s full lab picture as part of routine care. Therefore, it may be easier to see early trends, such as a declining eGFR on admission, and use that data to recommend dose adjustments.

Regardless of the setting, the uACR is worth keeping on the radar. Proteinuria is one of the earliest detectable signs of kidney damage, but many high-risk patients, especially those with diabetes or hypertension, aren’t being screened annually as they should be.

Counseling patients on kidney disease

Patients with kidney disease or at high risk of kidney disease may need special attention from pharmacists in both clinical and retail settings. Pharmacists can help make sure patients have the information they need between healthcare provider visits.

Review medications at every visit 

Many patients are on several medications, with more than four in 10 older adults taking five or more prescription medications. These medications can change between provider visits, so it’s important to monitor how these drugs affect kidney health. Pharmacists can then recommend dosage adjustments or other medication changes. 

Educate patients on the signs of worsening kidney function 

Many patients are unaware of how kidney disease progresses. Signs of worsening kidney function may include edema in the legs or ankles, persistent fatigue, foamy urine, and decreased urine output. All of these may be potential red flags to mention to a provider. 

Remind patients about regular kidney function testing 

Many patients often need regular lab visits, especially those with hypertension or diabetes. However, a lot of them may be skipping their yearly lab tests. A quick reminder from a pharmacist can help patients stay on track with regular kidney function testing and catch potential problems early. 

Mention lifestyle changes that support kidney health 

Patients with CKD may need to be reminded about certain lifestyle changes to support kidney health. That might include keeping blood pressure and blood sugar levels in check, limiting sodium intake, staying active, and avoiding smoking to help curb the progression of CKD. 

Counsel on potential risks of OTC drugs

Counseling on OTC medications is one of the most impactful ways for pharmacists to help patients improve kidney health. For example, patients with CKD typically need to avoid NSAIDs like ibuprofen or naproxen for pain relief. Instead, you might recommend acetaminophen. It’s also important to ask about herbal supplements patients may be taking, since some, including those that contain aristolochic acid, can be nephrotoxic. 

Bottom line

While kidney disease is a silent condition that can affect millions of Americans, pharmacists can do their part to help prevent or manage it. Whether it’s in a community pharmacy, hospital, or clinic, pharmacists have direct contact with patients who may not be aware of potential kidney risks. Medication management, education, and OTC counseling are all ways patients can get the information they need to protect their kidney health long-term.