Pain Relievers and Your Kidneys—What to Know About NSAIDs

person holding diagram of kidneys on lower back to demonstrate organ placement on human body.

Reaching for a pain reliever can feel automatic—whether it’s for a headache, sore back, or arthritis flare. During National Kidney Month, it’s a good time to pause and understand how some common pain medications, especially nonsteroidal anti‑inflammatory drugs (NSAIDs), can affect kidney health.

NSAIDs include familiar over‑the‑counter options like ibuprofen and naproxen, as well as some prescription medications. They’re effective for pain and inflammation, but they aren’t risk‑free, particularly for certain people and in certain situations.

Why NSAIDs matter for kidney health

Your kidneys rely on steady blood flow to filter waste and balance fluids. NSAIDs work by blocking enzymes involved in inflammation, but those same pathways also help maintain blood flow to the kidneys. When that balance is disrupted, kidney function can be affected. Sometimes the effects happen suddenly, and sometimes they can occur over time.

For many healthy adults using NSAIDs occasionally and as directed, the risk may be low. But frequent use, higher doses, dehydration, or underlying health conditions can increase the chance of kidney problems.

Who should be especially cautious with NSAIDs?

According to kidney health guidance, extra caution is important if you:

Have chronic kidney disease (CKD) or reduced kidney function
Have diabetes, high blood pressure, heart failure, or liver disease
Are 60 or older, since kidney function naturally declines with age
Take certain medications that affect kidney blood flow, such as ACE inhibitors (e.g., lisinopril, enalapril), ARBs (e.g., losartan, valsartan), or diuretics or “water pills” (e.g., furosemide, hydrochlorothiazide), which when combined with NSAIDs, especially during dehydration or illness, can increase stress on the kidneys and raise the risk of kidney injury.
Are sick with vomiting, diarrhea, fever, or anything that can cause dehydration

In these situations, NSAIDs can further reduce blood flow to the kidneys and increase the risk of acute kidney injury, especially if taken during illness or fluid loss.

Hydration myths: Can drinking more water make NSAIDs safe?

Staying hydrated is important for overall kidney health, but hydration does not “cancel out” NSAID risk.

One common myth is that drinking extra water makes NSAIDs safe for everyone. In reality, while dehydration raises the risk of kidney injury, simply drinking more water does not fully protect the kidneys if NSAIDs aren’t appropriate for you in the first place. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) specifically warns that NSAIDs can be harmful during times of illness or dehydration and that planning ahead for pain management is key^[1].

Bottom line: hydration helps, but it’s not a guarantee—and it’s not a substitute for choosing the right medication.

Safer pain‑management questions to ask

If you need pain relief and want to protect your kidneys, your Express Scripts pharmacist or healthcare provider can help. Consider asking:

Is this pain reliever safe for my kidneys, given my health conditions?
What’s the lowest effective dose, and how long can I take it safely?
Are there non‑NSAID options I should consider?
Should I stop this medication if I get sick, dehydrated, or can’t keep fluids down?
Do any of my prescriptions interact with this pain reliever?

NIDDK encourages patients to keep an up‑to‑date medication list and to ask pharmacists specifically how over‑the‑counter products may affect kidney health1.

What about alternatives to NSAIDs?

For some people, acetaminophen may be an option for pain relief because it works differently than NSAIDs. However, it still needs to be used carefully and within recommended limits, especially for those with liver conditions. Topical pain relievers or non‑drug approaches like heat, physical therapy, or stretching may also play a role, depending on the type of pain.

There’s no one‑size‑fits‑all solution. The safest choice depends on your health history, other medications, and how often you need pain relief.

Red flags: When to seek help

Kidney problems don’t always cause symptoms right away. If you’ve been using NSAIDs—especially regularly—contact a healthcare professional if you notice:

Swelling in the legs, ankles, or feet
Less frequent urination or very dark urine
Unusual fatigue, confusion, or trouble concentrating
Sudden weight gain from fluid retention
Blood pressure that’s harder to control

These can be signs that the kidneys are under stress and need prompt evaluation.

The takeaway for National Kidney Month

Pain relief matters, but protecting your kidneys matters too, especially when it comes to everyday medications like NSAIDs. Because kidney disease can progress quietly, understanding your personal risk, knowing when to be cautious, and planning ahead for times of illness or dehydration can make a meaningful difference. Even medications sold over the counter deserve careful consideration when kidney health is part of the picture.

That’s where Express Scripts^® Pharmacy can help. If your benefits include Express Scripts Pharmacy, you have 24/7 access to specially trained pharmacists who can review your medications, answer questions about NSAIDs and kidney safety, and help you identify safe pain‑management options based on your health history. A quick conversation with a pharmacist can help ensure your pain‑relief plan supports both day‑to‑day comfort and long‑term kidney health during National Kidney Month and all year long.