Many people take medicines every day without realizing that some medications can affect kidney function.

That does not mean these medicines are unsafe or should be avoided. In fact, many are extremely useful and sometimes essential. The important issue is that certain medicines can become risky when taken at high doses, for long periods, during dehydration, or when kidney function is already reduced.

The kidneys filter waste from the blood and help regulate fluid, electrolytes, and blood pressure. Because many medicines either pass through the kidneys or affect blood flow to them, kidney function can influence how safely a medication can be used.

Here are eight medication groups worth knowing about.

1. NSAID Painkillers

Nonsteroidal anti-inflammatory drugs, commonly called NSAIDs, are among the most important medications to watch when it comes to kidney health.

Examples include:

• Ibuprofen
• Naproxen
• Diclofenac tablets or capsules
• Meloxicam
• Indomethacin
• Celecoxib
• Ketorolac

NSAIDs can reduce blood flow through the kidneys. High doses or long-term use can increase the risk of acute kidney injury or worsen existing chronic kidney disease. The risk can be greater when someone is dehydrated or has other medical conditions affecting kidney function.

This is one reason people with chronic kidney disease are generally advised not to self-treat with NSAIDs without medical guidance.

Important distinction

A medication being available over the counter doesn’t mean it is appropriate for everyone.

Always check the active ingredients in painkillers and cold medicines because NSAIDs may be included in combination products.

2. High-Dose Aspirin

Aspirin deserves special attention because its effects depend partly on the dose.

Low-dose aspirin may be prescribed to certain people for cardiovascular protection. It should not automatically be considered harmful to the kidneys when used as prescribed.

However, higher doses of aspirin used for pain relief can act like an NSAID and may reduce blood flow to the kidneys. The National Kidney Foundation specifically identifies doses above 325 mg per day as a kidney concern.

Never stop prescribed low-dose aspirin without discussing it with your healthcare professional.

3. Certain Antibiotics

Many antibiotics are eliminated through the kidneys.

This doesn’t mean antibiotics should be avoided. Treating a serious infection is often much more important than the potential medication risk.

However, people with reduced kidney function may need a different dose or dosing schedule. Some antibiotics can also directly contribute to kidney injury in certain circumstances.

If you have kidney disease and receive an antibiotic, ask whether the dose has been adjusted for your kidney function.

4. Proton Pump Inhibitors

Proton pump inhibitors, or PPIs, are commonly used to reduce stomach acid.

Examples include:

• Omeprazole
• Pantoprazole
• Lansoprazole
• Esomeprazole

These medicines can be very effective for conditions such as acid reflux and certain ulcers.

However, PPIs have been associated with certain kidney problems, including acute interstitial nephritis, and long-term use should have an appropriate medical reason.

That doesn’t mean everyone taking a PPI will develop kidney disease. If you take one regularly for months or years, it’s reasonable to ask your healthcare professional whether you still need it and whether the dose remains appropriate.

5. Lithium

Lithium is an important medication used primarily to treat bipolar disorder and certain other psychiatric conditions.

It has a narrow therapeutic range, meaning blood concentrations need to remain within a specific range.

Long-term lithium treatment can affect kidney function in some people. Dehydration, changes in salt intake, and interactions with other medications can also affect lithium levels.

Because lithium can be an essential treatment, the answer isn’t simply to stop taking it. People prescribed lithium generally need appropriate monitoring of blood levels and kidney function.

Never stop lithium suddenly without medical supervision.

6. Diuretics or “Water Pills”

Diuretics help the body remove excess salt and water and are commonly prescribed for high blood pressure, heart failure, and some kidney conditions.

Examples include:

• Furosemide
• Torsemide
• Hydrochlorothiazide

These medicines can be extremely beneficial, but excessive dosing or dehydration can contribute to kidney problems.

The National Kidney Foundation notes that diuretics can cause dehydration and electrolyte abnormalities if the dose is too high for a person’s kidney function.

If you’re taking a diuretic, don’t dramatically increase or restrict your fluid intake without medical advice.

7. ACE Inhibitors and ARBs

This category requires an important clarification.

ACE inhibitors and ARBs can cause a small change in kidney blood tests after starting treatment, but they are not simply kidney-damaging medicines.

In fact, they are commonly used to protect the kidneys in people with conditions such as high blood pressure and protein in the urine. They can slow the progression of certain types of chronic kidney disease.

Examples include:

• Lisinopril
• Ramipril
• Enalapril
• Losartan
• Valsartan
• Irbesartan

The problem can arise when these medicines are combined with factors such as dehydration, NSAIDs, or certain diuretics.

This combination can increase the risk of acute kidney injury, sometimes referred to as the “triple whammy.”

This is why kidney function and potassium are often monitored after starting or changing these medicines.

8. Oral Sodium Phosphate Preparations

Some people encounter these medications when preparing for a colonoscopy.

Oral sodium phosphate preparations work by drawing water into the bowel, but they can cause serious kidney problems in susceptible people.

The National Kidney Foundation notes particular concerns for people with chronic kidney disease, people over 55, and people taking medications such as NSAIDs, ACE inhibitors/ARBs, or diuretics.

Other bowel-preparation options may be available, so anyone with kidney disease should discuss the safest preparation with their healthcare professional before a colonoscopy.

Why Are These Medicines Still Sold?

This is an important question.

The fact that a medication can affect kidney health does not mean it is inherently unsafe.

Medicines are used because their benefits can outweigh their risks when they are prescribed or taken appropriately.

For example:

• NSAIDs can provide valuable pain and inflammation relief.
• Antibiotics can treat potentially dangerous infections.
• Diuretics can control fluid overload and blood pressure.
• ACE inhibitors and ARBs can protect kidney function in appropriate patients.
• Lithium can be an important treatment for bipolar disorder.
• PPIs can effectively treat significant acid-related conditions.

The goal is not to frighten people away from useful medications.

The goal is to use the right medicine, at the right dose, for the right person, with appropriate monitoring.

Who Is More Vulnerable to Medication-Related Kidney Problems?

The risk can be higher in people who already have:

• Chronic kidney disease
• Diabetes
• High blood pressure
• Heart failure
• Dehydration
• Older age
• Multiple medications
• Previous episodes of acute kidney injury

People with reduced kidney function may also need lower doses or different dosing schedules because medicines can remain in the body longer.

Warning Signs That Shouldn’t Be Ignored

Medication-related kidney problems don’t always cause obvious symptoms in the beginning.

However, seek medical advice if you develop symptoms such as:

• Much less urine than usual
• New swelling in the legs, ankles, or around the eyes
• Unusual weakness
• Persistent nausea or vomiting
• Shortness of breath
• Confusion
• Significant changes in blood pressure
• Sudden unexplained fatigue

Sudden or severe symptoms may require urgent evaluation.

How to Protect Your Kidneys When Taking Medicines

A few simple habits can reduce avoidable medication-related problems.

Keep an Updated Medication List

Include prescriptions, over-the-counter medicines, vitamins, supplements, and herbal products.

Check Before Taking OTC Painkillers

If you have kidney disease, heart disease, high blood pressure, or take blood-pressure medicines, ask a healthcare professional before using NSAIDs.

Stay Properly Hydrated

Dehydration can increase the risk associated with certain medications, particularly NSAIDs and some combinations of blood-pressure medicines and diuretics.

Don’t Double Up on Similar Ingredients

Some cold, flu, and pain products contain the same active ingredients. Read labels carefully.

Have Kidney Function Checked When Appropriate

Blood tests such as creatinine and estimated glomerular filtration rate (eGFR) can help healthcare professionals determine how well the kidneys are functioning.

Don’t Stop Prescribed Medicines on Your Own

Stopping certain medicines abruptly can be dangerous. Instead, ask your doctor or pharmacist whether a medication is still appropriate.

One Combination Deserves Special Attention

One of the most important medication combinations to recognize involves:

An ACE inhibitor or ARB + a diuretic + an NSAID

Each medication may have a legitimate purpose, but together—particularly during dehydration—they can substantially increase the risk of acute kidney injury.

This doesn’t mean someone should discontinue any of these medicines without medical advice. It means the combination deserves appropriate monitoring and professional guidance.

Final Thoughts

There isn’t a simple list of “eight pills that destroy your kidneys.”

Some medications can affect kidney function, while others primarily require dose adjustments because the kidneys remove them from the body. Some medicines that sound concerning, such as ACE inhibitors and ARBs, can actually protect kidney function in the right patients.

The real issue is individual risk.

Your kidney function, age, hydration, medical conditions, medication combinations, dose, and duration of treatment all matter.

If you’re taking several medications—or have chronic kidney disease—ask your doctor or pharmacist to review your complete medication list. That simple review can help identify unnecessary medicines, potentially risky combinations, and doses that may need adjustment.

Most importantly, don’t stop a prescribed medicine because of an alarming headline. Talk to a healthcare professional first.