Why Can’t You Use NSAIDs and Steroids Together?

Combining NSAIDs like ibuprofen with corticosteroids like prednisone sharply raises your risk of stomach ulcers and gastrointestinal bleeding. One large epidemiological study found that people taking both drugs simultaneously faced a risk of peptic ulcer disease roughly fifteen times higher than people taking neither drug. That finding alone explains why most prescribers treat the combination as something to avoid whenever possible, though the interaction goes beyond the gut and the real-world picture has layers worth understanding.

What Each Drug Does to Your Stomach on Its Own

Your stomach lining survives its own acid bath thanks largely to prostaglandins, hormone-like compounds that stimulate mucus production, promote bicarbonate secretion, maintain blood flow to the stomach wall, and help damaged cells repair themselves. NSAIDs work by blocking the cyclooxygenase enzymes that produce prostaglandins, which is exactly how they reduce pain and inflammation. The catch is that the same prostaglandin suppression that eases a swollen knee also strips away one of the stomach’s main defenses.¹ With chronic NSAID use, this prostaglandin deficit makes ulcers a genuine clinical concern.²

The damage is not purely about prostaglandin loss. Research on mice lacking the cyclooxygenase enzymes showed that knocking out one enzyme alone does not produce spontaneous ulcers; both have to be inhibited simultaneously, and additional mechanisms like direct contact between the drug and the stomach lining play a role.³ NSAIDs also appear to shift the metabolism of arachidonic acid toward producing leukotrienes, which are themselves injurious to the mucosa, compounding the harm from lost prostaglandins.⁴

Corticosteroids, on the other hand, work upstream. One key mechanism for their anti-inflammatory power is blocking the enzyme phospholipase A2, which is responsible for releasing arachidonic acid from cell membranes in the first place.⁵ In lab studies, dexamethasone nearly completely blocked phospholipase A2 release in cultured smooth muscle cells, working through both gene-level suppression and interference with the protein after it was made.⁶ Glucocorticoids also stimulate the release of anti-phospholipase proteins, sometimes called macrocortin or lipomodulin, that further dial down arachidonic acid availability.⁷

So steroids cut off arachidonic acid supply, and NSAIDs block what little arachidonic acid remains from being converted into protective prostaglandins. Together, the stomach’s prostaglandin-driven defenses take a double hit.

The Combined Risk Is Not Simply Additive

The most striking data on the combination come from studies that tracked actual ulcer outcomes. In a well-known case-control study published in the Annals of Internal Medicine, corticosteroid users who were not taking NSAIDs had essentially no increased risk of peptic ulcer disease compared to non-users. The estimated relative risk was just 1.1. But corticosteroid users who were also taking NSAIDs had a relative risk of 4.4 for peptic ulcer, and the combination of both drugs pushed the overall risk to about fifteen times that of people using neither.⁸

That finding upended an older clinical assumption. For decades, steroids were considered a major independent cause of stomach ulcers. This study suggested that corticosteroids alone may be relatively benign to the stomach lining, and that much of the ulcer risk historically attributed to steroids was actually driven by people who happened to be taking NSAIDs at the same time. The interaction between the two was the real danger.

A separate large epidemiological analysis looked at upper gastrointestinal complications more broadly and found a clear dose-response relationship. Combining steroids with low-to-medium NSAID doses produced an odds ratio of about 4.0 for upper GI complications. At high NSAID doses, the odds ratio climbed to roughly 12.7.⁹ The researchers’ conclusion was blunt: whenever possible, anti-inflammatory drugs should be used alone and at the lowest dose that works.

Why Steroids Amplify NSAID Damage

It might seem paradoxical that steroids, which are powerful anti-inflammatory agents, would make inflammation-driven stomach damage worse. The explanation lies in what prostaglandins actually do in the gut. Their role there is not about controlling inflammation; it is about keeping the mucosal barrier intact. Prostaglandins trigger the mucus layer that coats the stomach wall, regulate the bicarbonate that neutralizes acid near the surface, and keep blood flowing to support repair of any minor damage.⁴

When NSAIDs reduce prostaglandin production, those protective functions weaken. Steroids then compound the problem by further limiting the raw material for prostaglandin synthesis. Because glucocorticoids inhibit phospholipase A2, less arachidonic acid gets freed from cell membranes, meaning less substrate is available for whatever cyclooxygenase activity the NSAID has not already blocked.⁵ Steroids also slow wound healing and suppress immune responses that would otherwise help the body patch up minor erosions before they become full-blown ulcers. The net result is a stomach lining that has lost its protective coating and simultaneously lost much of its ability to repair itself.

Beyond the Gut

Gastrointestinal bleeding gets the most attention, and for good reason, but the interaction between NSAIDs and steroids causes problems in other organ systems too.

Both drug classes independently raise blood pressure. NSAIDs promote sodium and water retention by suppressing renal prostaglandins, and corticosteroids have mineralocorticoid effects that do the same. A review in the Journal of Clinical Hypertension identified NSAIDs and steroids as among the most clinically significant prescription drugs affecting blood pressure.¹⁰ For someone already managing hypertension, stacking both drugs can undermine blood pressure control and raise cardiovascular risk.

Kidney function is another shared vulnerability. Prostaglandins help maintain blood flow to the kidneys, and NSAIDs compromise that. Steroids, through their effects on fluid balance and blood pressure, add further renal stress. In a controlled study in dogs, combining an NSAID with prednisolone significantly reduced both the rate of blood flow through the kidneys and the overall filtration rate, and caused kidney-related abnormalities in urine that were not seen with either drug alone.¹¹ Even selective COX-2 inhibitors, which were designed to spare the stomach, produced serious kidney and platelet effects when paired with prednisolone in the same study. The researchers concluded that the combination may be contraindicated regardless of which type of NSAID you use.

Older adults face compounded risks from chronic NSAID use, including interactions with corticosteroids and other common medications like blood thinners.¹² For people over 65, who are already more likely to have thinner stomach linings, reduced kidney reserves, and higher baseline blood pressure, the margin of safety with this combination narrows considerably.

When Doctors Prescribe Both Anyway

Despite the risks, there are clinical situations where a patient ends up on both an NSAID and a corticosteroid. Rheumatoid arthritis is the classic example. A person on long-term low-dose prednisone for autoimmune inflammation may also need an NSAID for acute pain flares. Some emergency and acute-care protocols have tested each drug class head-to-head against the other to see which works better solo. For instance, a randomized trial in gout-like arthritis compared oral prednisolone with acetaminophen against oral indomethacin (a strong NSAID) with acetaminophen, treating each as an alternative rather than a combination.¹³ The general clinical impulse is to pick one anti-inflammatory approach, not layer them.

When the combination is unavoidable, doctors typically reach for a gastroprotective strategy. Proton pump inhibitors, the class of acid-suppressing drugs that includes omeprazole and pantoprazole, can reduce the risk of ulcers in patients on NSAIDs. One review of the evidence found that a standard NSAID plus a PPI may be at least as effective at preventing ulcer recurrence as switching to a COX-2 selective inhibitor. The same review also noted that gastroprotective strategies are underused even in high-risk patients, including those on concurrent corticosteroids.¹⁴ If you’re on both drugs, you should absolutely ask your prescriber whether a PPI or another stomach-protecting measure is warranted.

Infection Masking

A less obvious danger with combining these drugs is that both can hide the signs of a developing infection. NSAIDs bring down fever and suppress the inflammatory signals your body uses to flag an infection. Steroids suppress the immune system more broadly, dampening the redness, swelling, and fever that would normally prompt you to seek medical attention. Together, they can create a situation where a serious infection progresses without obvious symptoms until it becomes much harder to treat.¹⁵

This is particularly relevant during acute respiratory infections, where the temptation to use both an anti-inflammatory and a steroid for symptom relief can be strong. But the very symptom relief that makes you feel better may be masking deterioration. Doctors navigating post-surgical recovery or treating patients with compromised immune systems pay close attention to this dynamic, because the usual clinical warning signs become unreliable when both drug classes are on board.

Effects on Bone and Tissue Healing

Both NSAIDs and corticosteroids independently interfere with bone metabolism, raising the question of what happens to healing when both are present. Laboratory research on bone marrow mesenchymal stem cells found that NSAIDs (both selective and non-selective) suppressed cell proliferation and arrested the cell cycle in these bone-forming precursor cells. Dexamethasone, a commonly used corticosteroid, decreased the osteogenic potential of mesenchymal stem cells as well.¹⁶

In practical terms, this means that someone recovering from a fracture or bone surgery faces a real concern if they’re taking both drug classes. Long-term corticosteroid use is already a recognized risk factor for osteoporosis, and adding an NSAID that further impairs bone cell function could slow the healing process. Orthopedic surgeons often prefer acetaminophen or other non-NSAID analgesics in the post-fracture period for exactly this reason, particularly when steroids are already part of the patient’s regimen for another condition.

Over-the-Counter Risks People Overlook

One reason this drug interaction catches people off guard is that it does not require two prescription bottles. Ibuprofen, naproxen, and aspirin are all NSAIDs available without a prescription. Someone put on a short course of prednisone for an allergic reaction or an asthma flare may casually reach for ibuprofen for a headache, not realizing they’ve just created the high-risk combination. The dose-response data make this especially concerning: even low-to-medium NSAID doses combined with steroids produced a fourfold increase in upper GI complication risk, and higher doses pushed it above twelvefold.⁹

Corticosteroids also show up in forms people may not think of as “steroids.” Methylprednisolone dose packs, dexamethasone for COVID-related symptoms, and even some injections for joint pain or back problems deliver systemic steroid exposure. Meanwhile, aspirin taken daily for heart protection is still an NSAID. Many patients on long-term low-dose aspirin do not mentally categorize it alongside ibuprofen, but the stomach does not make that distinction. If you’re on any corticosteroid for any reason, it is worth reviewing every other medication and supplement you take, including the over-the-counter ones, with your pharmacist.

What Veterinary Research Adds

Some of the clearest experimental data on this drug interaction come from veterinary studies, where researchers can control variables more tightly than in human observational work. The dog study mentioned earlier did not just document gut damage. It measured kidney filtration rates, platelet function (via bleeding times), and urinary markers of kidney tubular injury. The group receiving both an NSAID and prednisolone showed significant abnormalities across all of these systems, including shedding of renal tubular cells in urine, a sign of direct kidney injury.¹¹ Even a COX-2 selective NSAID, which is marketed partly on the basis of better GI safety, could not avoid these problems when paired with a steroid.

Veterinarians tend to be especially wary of this combination in practice. Dogs and cats sometimes receive steroids for allergies or immune conditions and NSAIDs for arthritis, and the crossover can happen when owners switch veterinarians or when one provider is unaware of another’s prescription. The washout period between stopping one drug and starting the other matters too, since both classes can linger in the body for days. This is a point that translates directly to human medicine: if your doctor is switching you from a steroid to an NSAID or vice versa, the gap between the two matters, and skipping it creates the same overlap risk as taking both at once.