Pills You Shouldn’t Take Without Checking First If You Care About Your Kidneys
Your kidneys work around the clock to filter waste from your blood, regulate fluid and electrolytes, and help control blood pressure.
But some medicines can put extra stress on the kidneys—particularly when they are taken at high doses, for long periods, during dehydration, or in people who already have reduced kidney function.
That doesn’t mean you should stop prescribed medication because you are worried about your kidneys. In fact, some medicines that affect kidney function can be extremely beneficial when used correctly.
The safer approach is to know which medications deserve extra caution and to discuss them with your doctor or pharmacist.
Here are eight important categories to know about.
1. Ibuprofen and Other NSAID Painkillers
Examples include:
- Ibuprofen
- Naproxen
- Diclofenac
- High-dose aspirin
These medicines belong to a group called nonsteroidal anti-inflammatory drugs, or NSAIDs.
NSAIDs can reduce blood flow to the kidneys. High doses, prolonged use, dehydration, older age, high blood pressure, diabetes, or existing kidney disease can increase the risk of kidney injury. (National Kidney Foundation)
Why this matters
Because many NSAIDs are sold without a prescription, people sometimes assume they are harmless simply because they are available over the counter.
Taking an occasional dose may be appropriate for some people, but regular or high-dose use should not be treated casually.
Safer approach: Ask your doctor or pharmacist which painkiller is appropriate for you, particularly if you have kidney disease, heart disease, high blood pressure, or take blood-pressure medicines.
2. Certain Antibiotics
Some antibiotics can cause kidney problems or accumulate in the body when kidney function is reduced.
The issue is not that you should avoid antibiotics altogether. Infections themselves can be dangerous, and antibiotics can be lifesaving.
Instead, certain antibiotics may require a dose adjustment based on your kidney function. Some can also directly contribute to kidney injury in susceptible patients. (National Kidney Foundation)
Why this matters
A dose that is appropriate for someone with normal kidney function may not be appropriate for someone with significantly reduced kidney function.
Safer approach: Tell your prescriber if you have kidney disease and make sure they know about all the medicines you take.
Never skip or stop an antibiotic prescribed for an infection simply because you are concerned about your kidneys.
3. Certain Antiviral Medicines
Some antiviral medicines are processed or eliminated through the kidneys and may require special dosing when kidney function is reduced.
In some situations, certain antiviral drugs can also contribute to kidney injury. (National Kidney Foundation)
Why this matters
Kidney function can change how much of a medicine remains in your bloodstream.
Your healthcare professional may therefore need to check your kidney function before prescribing certain antiviral treatments or adjust the dose accordingly.
Safer approach: Tell your doctor about any history of kidney disease before starting an antiviral medication.
4. Some Diuretics—or “Water Pills”—Need Careful Monitoring
Diuretics help your body remove excess salt and water. They are commonly used to treat high blood pressure, heart failure, and fluid retention.
They are not inherently bad for your kidneys.
However, they can contribute to dehydration or changes in electrolytes in some circumstances. If you become significantly dehydrated, kidney function can deteriorate.
Why this matters
The combination of illness, vomiting, diarrhea, poor fluid intake, or excessive fluid loss with certain medicines can put considerable stress on the kidneys.
Safer approach: Take diuretics exactly as prescribed and ask your healthcare professional what to do if you develop significant vomiting, diarrhea, dehydration, or another illness that prevents you from drinking normally.
Do not simply stop a prescribed diuretic without medical advice.
5. ACE Inhibitors Require Kidney Monitoring—But They Aren’t Simply “Kidney-Damaging”
Examples include:
- Lisinopril
- Ramipril
- Enalapril
This is an important distinction.
ACE inhibitors can cause a rise in creatinine or changes in kidney function in certain circumstances, particularly after starting treatment or when someone becomes dehydrated. But they are also widely used to protect the kidneys in specific patients, particularly those with certain forms of chronic kidney disease and protein in the urine.
So calling ACE inhibitors “kidney-damaging pills” without context would be misleading.
Why this matters
Doctors commonly monitor kidney function and potassium after starting or changing an ACE inhibitor.
The goal is to make sure the medication is producing its intended benefit without causing an unacceptable change in kidney function.
Safer approach: Don’t stop an ACE inhibitor because you read that it can affect the kidneys. Have your kidney function and potassium monitored as recommended.
6. ARBs Also Need Monitoring
Angiotensin receptor blockers (ARBs) include medicines such as:
- Losartan
- Valsartan
- Irbesartan
- Candesartan
Like ACE inhibitors, ARBs can affect kidney function and potassium levels. But they can also provide important cardiovascular and kidney benefits in appropriately selected patients.
Why this matters
The concern becomes greater when ARBs are combined with other medicines that affect kidney blood flow or fluid balance.
One particularly important combination is an ARB, a diuretic, and an NSAID. Under certain circumstances, this combination can substantially increase the risk of acute kidney injury.
Safer approach: Make sure your doctor or pharmacist knows if you regularly use NSAID painkillers while taking an ARB.
7. Proton Pump Inhibitors Shouldn’t Be Used Indefinitely Without a Reason
Proton pump inhibitors (PPIs) are commonly used for acid reflux and other stomach conditions.
Examples include:
- Omeprazole
- Pantoprazole
- Lansoprazole
- Esomeprazole
These medicines are useful and appropriate for many people.
However, kidney problems have been associated with PPI use, including a condition called acute interstitial nephritis, an inflammatory injury of the kidneys.
That does not mean everyone taking a PPI will develop kidney damage.
Why this matters
People sometimes continue acid-suppressing medication for months or years without reviewing whether they still need it.
Safer approach: If you have been taking a PPI long-term, periodically ask your healthcare professional whether you still need it and whether your treatment should be adjusted.
Never discontinue a long-term prescription solely because of an internet warning.
8. Lithium Requires Particularly Careful Kidney Monitoring
Lithium is an important treatment for certain psychiatric conditions, but it has a narrow therapeutic range and is closely connected to kidney function.
The kidneys eliminate lithium from the body. Reduced kidney function can therefore cause lithium levels to rise, potentially leading to toxicity.
Why this matters
Dehydration, changes in fluid or salt intake, and interactions with other medicines can alter lithium levels.
Long-term lithium treatment can also affect kidney function in some people.
Safer approach: If you take lithium, keep your scheduled blood tests and kidney-function monitoring appointments. Do not change your lithium dose yourself.
