A wide range of common medications can damage the kidneys, from over-the-counter painkillers to prescription antibiotics and chemotherapy drugs. Roughly 28% of acute kidney injury cases in people with existing kidney disease are linked to medications, and many of these injuries happen outside the hospital with drugs people take every day. Understanding which medications pose a risk, and why, can help you recognize early warning signs and have better conversations with your prescriber.
Over-the-Counter Painkillers (NSAIDs)
Nonsteroidal anti-inflammatory drugs like ibuprofen (Advil, Motrin), naproxen (Aleve), and aspirin are among the most common culprits. Your kidneys rely on small signaling molecules called prostaglandins to keep blood flowing through their filtering units. NSAIDs block the production of those molecules, which narrows a critical blood vessel at the entrance to each filter. In a healthy, well-hydrated person taking an occasional dose, this effect is minor and reversible. But when blood flow to the kidneys is already compromised, even short courses can trigger acute kidney injury.
The people most vulnerable are those who are dehydrated, older adults, anyone with existing kidney disease, and people taking blood pressure medications that also affect kidney blood flow (like ACE inhibitors or diuretics). Combining an NSAID with both a diuretic and an ACE inhibitor, sometimes called the “triple whammy,” is a well-known recipe for sudden kidney damage. Chronic daily use over months or years can also cause a slower, more insidious form of kidney disease involving scarring of the tissue between the kidney’s filtering tubes.
Antibiotics That Stress the Kidneys
Several classes of antibiotics are directly toxic to kidney cells, particularly the cells lining the tiny tubes that process urine.
Aminoglycosides (such as gentamicin and tobramycin) are among the most nephrotoxic antibiotics in clinical use. They accumulate inside kidney cells and cause them to die, a process called acute tubular necrosis. Risk climbs with higher doses and longer treatment courses. These drugs are typically reserved for serious infections precisely because of this toxicity.
Vancomycin, used for resistant bacterial infections like MRSA, also carries significant kidney risk. In clinical studies, nephrotoxicity rates nearly tripled when blood levels of the drug ran high: about 6% of patients with lower blood concentrations developed kidney injury compared with 18% of those with higher concentrations. Treatment lasting more than 14 days and especially beyond 21 days further increased risk. High daily doses pushed nephrotoxicity rates to nearly 35%, compared with roughly 11% for lower doses.
Other antibiotics with nephrotoxic potential include amphotericin B (an antifungal), certain sulfonamides, and some antivirals used for HIV and herpes. In most cases, the damage is dose-dependent and at least partially reversible if caught early.
Blood Pressure and Heart Medications
This category is tricky because many blood pressure drugs protect the kidneys long-term while posing short-term risks. ACE inhibitors (like lisinopril and enalapril) and ARBs (like losartan and valsartan) reduce pressure inside the kidney’s filtering units, which slows the progression of chronic kidney disease. But they can also cause a temporary rise in creatinine (a waste product your kidneys filter) when first started, and they can trigger acute kidney injury in someone who becomes dehydrated or whose kidney blood flow is already low.
Diuretics, or “water pills,” reduce blood volume. That’s helpful for blood pressure and heart failure, but excessive fluid loss can starve the kidneys of blood flow. Loop diuretics like furosemide are more potent and carry higher risk than milder thiazide diuretics, though both can contribute to kidney problems in the wrong circumstances.
Chemotherapy Drugs
Cisplatin, a platinum-based chemotherapy drug used for bladder, lung, ovarian, and other cancers, is one of the most kidney-toxic medications in existence. About one-third of patients receiving cisplatin develop some degree of kidney impairment. The drug accumulates in kidney cells at concentrations five times higher than in the blood, directly damaging the cells that line the kidney’s filtering tubes.
Oncologists try to reduce this risk by aggressively hydrating patients before and after infusions. When possible, they may substitute carboplatin, a related drug with lower kidney toxicity. Despite these precautions, kidney function monitoring during cisplatin treatment is intensive because damage can progress quickly.
Other chemotherapy agents linked to kidney injury include methotrexate (which can crystallize in kidney tubes), ifosfamide, and certain targeted therapies. The risk varies widely depending on the specific drug, dose, and the patient’s baseline kidney function.
Lithium and Psychiatric Medications
Lithium, a mainstay treatment for bipolar disorder, is a well-established cause of chronic kidney disease with long-term use. Unlike most drug-induced kidney injuries, lithium damage tends to be gradual and sometimes irreversible. Tiny cysts can form in kidney tissue after as little as one year of treatment. A large Danish registry study found that people who filled 60 or more lithium prescriptions had roughly 2.5 times the risk of developing chronic kidney disease compared with the general population.
The damage occurs because lithium concentrates in the kidney’s collecting ducts, the final stretch of tubing where urine is concentrated. Over time, this causes inflammation and scarring in the surrounding tissue. One of the earliest signs is that the kidneys lose their ability to concentrate urine, leading to excessive thirst and frequent urination. People on long-term lithium therapy need regular kidney function testing, typically every few months.
Contrast Dye Used in Imaging
The iodine-based contrast agents injected during CT scans, angiograms, and certain other imaging studies can cause a form of kidney injury known as contrast-induced nephropathy. It’s defined as a meaningful rise in creatinine within 48 to 72 hours after the dye is administered.
For most people, the risk is low, around 0.6% to 2.3%. But in certain groups, particularly people with existing kidney disease, diabetes, heart failure, or dehydration, the risk jumps to as high as 20%. The combination of reduced kidney function and diabetes is especially dangerous. Hospitals typically check kidney function before contrast procedures and may use extra IV fluids or lower-volume dye protocols for high-risk patients.
Herbal Supplements and OTC Products
Some herbal and dietary supplements cause serious kidney damage that people rarely anticipate because these products are perceived as “natural.” The spectrum of injuries reported in the medical literature includes kidney stones, inflammation of the kidney’s filtering units, tissue death, acute kidney failure, and progression to end-stage kidney disease requiring transplant.
The most notorious example involves aristolochic acid, a compound found in certain traditional Chinese herbs, particularly those historically used in weight-loss formulas. Aristolochic acid causes a distinctive pattern of kidney scarring and is also linked to urinary tract cancers. Cases originally surfaced in Belgium in the 1990s when a weight-loss clinic inadvertently substituted a toxic herb for an intended ingredient, and reports have continued worldwide.
Other supplements associated with kidney harm include high-dose creatine (especially with inadequate hydration), excessive vitamin C (which can form kidney stones), and certain herbal teas. Because supplements aren’t regulated the same way as prescription drugs, contamination and mislabeling add further unpredictable risk.
Proton Pump Inhibitors (PPIs)
Acid reflux medications like omeprazole (Prilosec), lansoprazole (Prevacid), and esomeprazole (Nexium) have been linked to chronic kidney disease in large population studies. The risk is most relevant for people who use these drugs continuously for months or years, not for occasional short courses. The mechanism isn’t fully understood, but PPIs appear to cause a type of inflammation in the kidney’s tissue that can silently progress. Because PPIs are available over the counter and widely used, many people take them for far longer than originally intended without realizing the potential kidney impact.
SGLT2 Inhibitors: A Confusing Exception
If you take a newer diabetes or heart failure medication like empagliflozin (Jardiance), dapagliflozin (Farxiga), or canagliflozin (Invokana), you may notice your kidney function numbers dip shortly after starting. This can look alarming, but it’s actually expected and not a sign of damage.
In clinical trials, about 28% to 45% of patients starting these drugs saw their estimated kidney filtration rate drop by more than 10% in the first two to four weeks. The average decline was around 3 to 4 points. Counterintuitively, the patients whose numbers dipped the most actually had better long-term outcomes, including slower kidney decline over years, than those whose numbers stayed flat. The initial dip reflects a change in pressure inside the kidney’s filters that is ultimately protective.
A drop greater than 30% is uncommon (occurring in only 3% to 4% of patients) and should prompt investigation for other causes like dehydration or a second nephrotoxic medication. But in general, SGLT2 inhibitors are kidney-protective drugs that just happen to look worrying on early lab work.
Reducing Your Risk
The single most practical step is awareness. If you take any of the medications above, especially combinations of them, periodic kidney function testing (a simple blood draw measuring creatinine) lets you catch problems early, when they’re most reversible. Staying well-hydrated matters more than most people realize, particularly when taking NSAIDs, lithium, or diuretics, because dehydration amplifies nearly every form of drug-related kidney injury.
If you use over-the-counter painkillers regularly, acetaminophen (Tylenol) is generally easier on the kidneys than NSAIDs, though it carries its own liver risks at high doses. For supplements, skepticism is warranted: “natural” does not mean safe for your kidneys, and the lack of regulatory oversight means you may not even know exactly what’s in the bottle. Keeping an updated medication list, including supplements, and sharing it with every prescriber you see is one of the simplest ways to prevent harmful drug combinations that put your kidneys at risk.