{"id":189263,"date":"2026-04-03T11:20:34","date_gmt":"2026-04-03T08:20:34","guid":{"rendered":"https:\/\/fendaf.ee\/uncategorized-et-en\/poletikuvastased-valuvaigistid\/"},"modified":"2026-10-06T22:19:07","modified_gmt":"2026-10-06T19:19:07","slug":"anti-inflammatory-painkillers-for-dogs","status":"publish","type":"post","link":"https:\/\/fendaf.ee\/en\/health\/anti-inflammatory-painkillers-for-dogs\/","title":{"rendered":"Anti-inflammatory painkillers for dogs: does \u2018safe\u2019 mean risk-free?"},"content":{"rendered":"

Anti-inflammatory painkillers, or NSAIDs, can give a dog in pain something very important back: the ability to get up, move, walk and live with less pain. In osteoarthritis, they are also among the best-studied pain-relieving medicines.<\/p>\n

This article did not come from a position of being against medicines in principle. Quite the opposite. My first German Shepherd, Bemmu, received quite a lot of Rimadyl during his life. When I started researching medicines more thoroughly for the first version of this article, however, I found that serious adverse reactions, including fatal ones, had also been reported after carprofen use.<\/p>\n

What bothered me most was that nobody had explained this risk context to me when the medicine was prescribed. I have heard the same from other dog owners as well.<\/p>\n

That does not mean Rimadyl is a \u2018bad medicine\u2019 or that dogs should not receive anti-inflammatory painkillers. Carprofen and other NSAIDs help a great many dogs. Untreated chronic pain is not a safe or neutral choice either: a dog in pain moves less, loses muscle mass and may experience a substantial decline in quality of life.<\/p>\n

The real question is whether the owner has enough information before making the decision.<\/p>\n

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FendaF\u2019s key question<\/p>\n

Not \u2018is an NSAID good or bad?\u2019, but: how much benefit is this dog likely to gain, which factors increase the risk of adverse effects, and how can that risk be reduced?<\/p>\n<\/div>\n

Arthritis and arthrosis are not quite the same thing<\/h2>\n

Before discussing painkillers, it helps to clarify two terms that are often mixed up: arthritis and arthrosis.<\/p>\n

Arthritis means inflammation of a joint. It may be caused by infection, an immune-mediated disorder or trauma, for example, and treatment can differ greatly depending on the cause.<\/p>\n

Arthrosis, or osteoarthritis, is a chronic degenerative joint disease involving changes in cartilage, bone, the joint capsule, synovium and other joint structures. It is often described simply as \u2018wear and tear\u2019, but that is not fully accurate: inflammation also plays an important role in osteoarthritis, and the disease affects the whole joint.<\/p>\n

The terminology can also be confusing. In this article, we use osteoarthritis, or OA, for chronic degenerative joint disease.<\/p>\n

FendaF\u2019s separate article on arthritis provides more background on the disease itself, exercise and supportive options.<\/p>\n

How safe is a \u2018safe\u2019 painkiller?<\/h2>\n

Calling a medicine \u2018safe\u2019 does not mean it is risk-free. Likewise, a long list of possible adverse effects does not automatically mean a medicine is bad or that your dog will experience those effects.<\/p>\n

Known NSAID risks include gastrointestinal injury, including ulcers and bleeding, kidney injury and liver injury. Most adverse reactions are not fatal, but some can be severe, and fatal cases have been described on rare occasions.<\/p>\n

It also matters which dogs were studied. A healthy young Beagle in a controlled safety study is not the same patient as a thirteen-year-old dog with osteoarthritis and heart or kidney disease, receiving a diuretic and potentially becoming dehydrated during an episode of diarrhoea. Results from one population cannot simply be transferred to another. See also: Dehydration in dogs<\/a><\/p>\n

We have also written an in-depth article on drug safety and why \u2018safe\u2019 does not mean the same thing for every patient.<\/p>\n

What do NSAID safety studies actually tell us?<\/h2>\n

A 2013 systematic review identified 64 prospective studies dealing with NSAID safety in dogs. The strength of evidence supporting the safety of carprofen, firocoxib and meloxicam was rated high. That matters and should not be minimised.<\/p>\n

At the same time, only three studies had at least 80% statistical power to detect adverse effects. The authors also noted that most studies were not optimally designed to evaluate safety and that many enrolled healthy, non-geriatric dogs.<\/p>\n

These are two different limitations. \u2018Only three studies\u2019 does not mean that only three studies used sick dogs. It means that only three of the 64 had at least 80% statistical power to detect adverse effects.<\/p>\n

A small study may simply miss a rare adverse event. If no severe reaction occurred in a study, that does not automatically mean the true risk is zero.<\/p>\n

How long is a \u2018long-term\u2019 study, really?<\/h2>\n

A dog may be diagnosed with osteoarthritis at eight years of age and live another six or eight years. Yet controlled long-term studies of many medicines are measured in months, sometimes around a year.<\/p>\n

A well-studied medicine does not necessarily mean we have equally strong controlled evidence for its use over eight weeks and over eight years.<\/p>\n

This does not mean the medicine becomes dangerous after the study period. It means that the further we move beyond the duration of controlled studies, the more our knowledge comes from clinical experience and pharmacovigilance rather than from controlled trials lasting for years.<\/p>\n

A safety study using several times the therapeutic dose is not an accelerated model of years of use either. A higher dose gives very valuable toxicological information, but it cannot provide the missing time or the missing patient. Increasing the dose does not speed up ageing or create, within six months, the comorbidities that develop over years.<\/p>\n

What do we actually know about the different anti-inflammatory painkillers?<\/h2>\n

This table is not a ranking of medicines. No single column tells us which medicine is \u2018the safest\u2019. A clinical trial in real dogs with OA, a controlled target-animal safety study and a long market history provide different kinds of information and complement one another.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
Active ingredient<\/td>\nStudy in real dogs with OA<\/td>\nLonger-term safety \/ market-information layer<\/td>\nWhat does this mean?<\/td>\n<\/tr>\n<\/thead>\n
Carprofen (e.g. Rimadyl)<\/td>\n805 dogs with OA, 84 days; separate controlled OA comparison study up to 134 days.<\/td>\nLong history of use. A signal of idiosyncratic liver injury is well recognised.<\/td>\nA very large amount of clinical and real-world information, but not multi-year controlled OA-treatment evidence.<\/td>\n<\/tr>\n
Firocoxib (Previcox)<\/td>\n1,002 dogs with OA, 40 days; 39 dogs with OA for 52 weeks, 25 completed the study.<\/td>\nIn the EU since 2004; post-authorisation safety information has expanded over time.<\/td>\nOne of the longer studies in real dogs with OA, but the one-year population was small.<\/td>\n<\/tr>\n
Meloxicam (e.g. Metacam)<\/td>\n217 dogs with OA, 14 days; 59 dogs with OA up to 112 days in a dose-reduction study.<\/td>\n26 weeks, 40 healthy Beagles, up to five times the dose in one target-animal safety study.<\/td>\nLarge clinical studies are short; the longer safety study used healthy young dogs.<\/td>\n<\/tr>\n
Robenacoxib (Onsior)<\/td>\n188 dogs with OA, 12 weeks; 125 on robenacoxib, 63 on carprofen.<\/td>\n6 months, 32 healthy young Beagles, at 1x, 3x and 5x doses.<\/td>\nA useful combination of clinical and controlled safety information, but not a multi-year study in multimorbid dogs.<\/td>\n<\/tr>\n
Cimicoxib (Cimalgex)<\/td>\n492 client-owned dogs, 30 days; prospective but open-label and uncontrolled study.<\/td>\nIn 2023 the EMA expanded safety information based on pharmacovigilance, including polyuria\/polydipsia and a warning about potentially fatal GI\/renal injury.<\/td>\nA good example of how official safety information can change more than a decade after launch.<\/td>\n<\/tr>\n
Mavacoxib (Trocoxil)<\/td>\n124 dogs with OA, 134 days compared with carprofen.<\/td>\nVery long half-life; in about 5% of OA patients it was estimated to exceed 80 days.<\/td>\nMonthly dosing may be an advantage, but it reduces flexibility if an adverse effect or health change occurs.<\/td>\n<\/tr>\n
Grapiprant (Galliprant)<\/td>\n285 dogs with OA enrolled, 262 in the efficacy analysis; 28 days.<\/td>\n9 months, 36 healthy 9-month-old Beagles. EMA added pancreatitis in 2023 and in 2026 decided to add GI ulceration as a very rare reaction.<\/td>\nThe EP4 mechanism is different, but that does not automatically prove better long-term safety.<\/td>\n<\/tr>\n
Enflicoxib (Daxocox)<\/td>\n109 real dogs with OA, 6 months; 83 on enflicoxib, 26 on placebo.<\/td>\nSeparate target-animal safety studies with multiple doses. In the EU since 2021.<\/td>\nNew does not mean poorly studied: six-month real-world OA data are strong, but the pharmacovigilance history is shorter than for older medicines.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

A long market history, a long controlled safety study and a long clinical trial in dogs with osteoarthritis are not the same thing. A medicine that has been on the market for eighteen years has not therefore been used for eighteen years in a controlled trial in dogs with osteoarthritis. Likewise, six months in healthy young Beagles does not show how the same medicine behaves for six months in an elderly dog with multiple diseases and multiple medicines.<\/p>\n

All three layers of evidence are valuable, but none directly shows what happens to an elderly multimorbid dog after years of daily treatment.<\/p>\n

This knowledge gap does not prove that multi-year treatment is dangerous. It simply means that we do not have the same type or strength of controlled evidence for its safety as we do for shorter treatment periods.<\/p>\n

Is long-term NSAID treatment inherently dangerous?<\/h2>\n

A 2010 systematic review defined long-term use as at least 28 consecutive days. Six of seven studies evaluating efficacy found greater clinical benefit with longer treatment, and across 14 studies assessing safety no association was found between study duration and adverse-event rate. The authors nevertheless stressed that robust long-term safety data from large dog populations are limited.<\/p>\n

So the existing evidence does not support the simple claim that \u2018every additional month of treatment makes an NSAID more dangerous\u2019. Nor does it prove that years of treatment will be problem-free for every dog.<\/p>\n

Long-term NSAID treatment may be entirely justified and may be essential to maintaining a good quality of life in some dogs. The decision should, however, be revisited over time because the dog, its diseases, other medicines and the benefit obtained from treatment can all change.<\/p>\n

Pain relief does not mean the joint is healthy<\/h2>\n

Pain has a protective function. An NSAID may reduce pain far faster than muscle strength, coordination or the joint\u2019s true load tolerance recover. The dog feels better and wants to do things again that the body may not yet be ready for.<\/p>\n

In a study of 805 dogs with OA treated with carprofen for 84 days, the authors noted that excessive physical activity caused recurrence of signs in some dogs.<\/p>\n

If a dog that could walk one kilometre in pain yesterday suddenly wants to run five after starting a painkiller, that does not mean its muscles and joint have become ready for a five-kilometre load overnight.<\/p>\n

This is not an argument against NSAIDs. Good pain control may be exactly what allows a dog to move again and rebuild muscle. The new mobility created by treatment simply needs to be turned into rehabilitation rather than immediate overload.<\/p>\n

Can suppressing inflammation interfere with tissue healing?<\/h3>\n

In integrative veterinary medicine, one sometimes encounters the idea that long-term pharmacological suppression of inflammation may interfere with normal tissue healing. The question is not entirely without basis.<\/p>\n

In canine osteotomy studies, prolonged carprofen use has been associated with slower bone healing. And in a 2011 study, six healthy Beagles received carprofen for 120 days after tibial osteotomy and healing was slower than in controls. In a 2019 study, the two-week carprofen group did not differ from controls in radiographic healing, whereas healing was poorer in the eight-week group.<\/p>\n

This cannot automatically be extrapolated to a joint with osteoarthritis. In an experimental OA study, carprofen instead reduced progression of early structural changes in cartilage and subchondral bone.<\/p>\n

Current canine evidence does not support the general claim that NSAIDs as a drug class accelerate structural joint damage in osteoarthritis. Bone-healing studies do, however, show why the question \u2018can suppressing inflammation affect some healing processes?\u2019 should not simply be dismissed.<\/p>\n

How do you make a genuinely informed decision?<\/h2>\n

When starting NSAID treatment, asking only \u2018Is this medicine safe?\u2019 is not enough. A more useful question is what we want this medicine to achieve in this particular dog\u2019s life.<\/p>\n

Is the goal for the dog to stand up independently again? To manage its normal walk? To use the stairs without pain? Or is the dog already moving reasonably well and the medicine would simply make movement a little easier?<\/p>\n

Imagine two dogs. One is a fourteen-year-old with severe osteoarthritis who can barely stand without an NSAID, but with the medicine walks, eats, interacts with the family and enjoys life again. The other is a younger dog that already moves fairly well without an NSAID but moves a little better with one. Even if the probability of an adverse reaction were the same for both, the same risk may not carry the same weight for the owner.<\/p>\n

An informed decision is not only about knowing how likely an adverse effect is. The owner also needs to know how serious that possible adverse effect could be. A small risk of temporary diarrhoea and an equally small risk of irreversible kidney injury or a fatal reaction are not the same thing when making a decision.<\/p>\n

A veterinarian can help assess medical risk and likely benefit. The owner\u2019s own risk tolerance is also a legitimate part of informed decision-making. Neither extreme, \u2018medicine at any cost\u2019 nor \u2018never use medicine\u2019, is automatically more correct.<\/p>\n

Oscar: a diagnosis does not automatically mean a daily medicine<\/h3>\n

Oscar developed joint problems at a relatively young age. I can now see that he no longer gets up exactly like a completely healthy young dog, but he gets up on his own, moves around and is happy to go for walks. My goal is not to use medicine to make his movement look as young as possible. The goal is for him to feel well.<\/p>\n

I do not know what would have happened if Oscar had received an NSAID every day for all these years. He might have tolerated it perfectly. Or he might not. As his owner, that uncertainty is part of the risk I have to weigh against the additional benefit the medicine would give him now.<\/p>\n

Lack of evidence does not prove harm, but it does not prove absence of harm either. If we do not have sufficient data on very long-term use in dogs like our own, part of the risk inevitably remains unknown. That uncertainty is not a reason to withhold necessary pain relief, but it is information that belongs in the benefit-risk assessment.<\/p>\n

NSAID treatment does not end when the prescription is written<\/h2>\n

With long-term NSAID treatment, writing the prescription begins the next stage: does the medicine provide enough benefit for this dog, and does the dog continue to tolerate it well?<\/p>\n

Before treatment begins, especially in an older dog or when longer treatment is planned, it may be sensible to know kidney and liver function and the dog\u2019s general health status. Baseline values provide a comparison point for later tests. A normal blood test at the start is not a guarantee that the medicine will still suit the dog one or five years later.<\/p>\n

If the veterinarian says kidney or liver function should be monitored regularly during treatment, or you read such advice in the product information, ask what \u2018regularly\u2019 means for your dog. When is the first recheck? When is the next one? Which symptoms, new illnesses or medication changes should trigger earlier testing?<\/p>\n

Do not assume the clinic will automatically call you at exactly the right time. A specific date or interval turns a vague recommendation into a real monitoring plan.<\/p>\n

A long-term monitoring plan should contain both a calendar and an emergency brake: when do we recheck the dog if everything is going well, and which changes mean we should not wait for the next scheduled appointment?<\/p>\n

A monitoring blood test is not the same thing as a treatment review. If kidney and liver values are normal but the dog\u2019s movement is not actually better on the medicine, \u2018the blood tests are fine\u2019 is not, by itself, a reason to continue the medicine for years.<\/p>\n

The absence of adverse effects alone is not enough reason to continue long-term treatment. In addition to being tolerated, the medicine must provide meaningful benefit to the dog.<\/p>\n

For more background on monitoring muscle mass and function, see FendaF\u2019s article on sarcopenia, or muscle loss.<\/p>\n

Switching NSAIDs and washout: why there is no universal number of days<\/h2>\n

If one NSAID does not provide enough pain relief or causes adverse effects, that does not automatically mean the dog cannot tolerate any NSAID. Dogs may respond differently to different active ingredients.<\/p>\n

Peku was a Labrador and lived to fourteen. One anti-inflammatory painkiller prescribed to him caused vomiting almost immediately. We no longer remember exactly which medicine it was. With another anti-inflammatory painkiller, the problem did not occur. This is one dog\u2019s experience, not evidence that one medicine is better than another.<\/p>\n

When switching NSAIDs, a drug-free or washout period may be needed. With some shorter-acting medicines, a veterinarian may choose a break of a few days; more conservative guidance often uses a longer interval. If the previous medicine was stopped because of an adverse effect, the start of a new treatment depends not only on pharmacology but also on whether the adverse effect has resolved.<\/p>\n

Do not use a number of days found online to switch your dog\u2019s medicines yourself. The point of these intervals is to help explain why a new NSAID may not be allowed to start the very next day.<\/p>\n

Trocoxil is an important exception<\/h3>\n

Mavacoxib, or Trocoxil, differs from the other medicines discussed in this article because it remains in the body for an exceptionally long time. The first dose is repeated after 14 days and the medicine is then given once a month; a treatment cycle must not exceed seven consecutive doses, or about six and a half months.<\/p>\n

In population pharmacokinetic data from OA patients, the typical terminal half-life was 44 days and in about five per cent of dogs it was estimated to exceed 80 days.<\/p>\n

The official Trocoxil product information states that another NSAID or a glucocorticoid must not be used at the same time or within one month after the final Trocoxil dose. The medicine is contraindicated, among other situations, in renal or hepatic impairment and heart failure, and dehydrated, hypovolaemic or hypotensive dogs must be considered at greater risk of renal toxicity.<\/p>\n

You can stop giving the tablets, but you cannot take back medicine that has already been administered. The longer a single dose acts in the body, the more important it is to be sure before giving it that this is the right medicine for the right patient.<\/p>\n

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An important exception to washout numbers<\/p>\n

The few-day washout often discussed for short-acting NSAIDs does not apply to mavacoxib. After Trocoxil, the official product information specifies at least one month before another NSAID or a glucocorticoid is used.<\/p>\n<\/div>\n

What should you do if your dog develops signs of an adverse effect?<\/h2>\n

The most commonly noticed NSAID-associated adverse effects are gastrointestinal signs: reduced appetite, vomiting, diarrhoea and changes in stool. In more severe cases, gastrointestinal ulceration and bleeding, kidney injury or liver injury may occur.<\/p>\n

A single episode of vomiting does not prove NSAID-induced kidney injury. At the same time, repeated vomiting or severe diarrhoea in a dog receiving a long-term NSAID is not something to simply watch for several days.<\/p>\n

Vomiting and diarrhoea can dehydrate a dog and reduce renal blood flow. That can make NSAID use riskier even in a dog that has previously tolerated the same medicine without problems.<\/p>\n

If a dog receiving an NSAID starts vomiting repeatedly, develops severe diarrhoea, black or bloody stool, blood in vomit, marked loss of appetite, unusual lethargy or weakness, yellow gums or whites of the eyes, or a significant change in drinking or urination, contact a veterinarian promptly. These signs do not prove the NSAID is the cause, but they need to be assessed. See also: How much water should a dog drink?<\/a><\/p>\n

With black tarry stool, bloody vomiting, jaundice, collapse or very severe weakness, it is not sensible to \u2018wait until morning\u2019; the dog needs urgent veterinary assessment.<\/p>\n

If the dog is vomiting, becomes dehydrated because of diarrhoea, or stops eating and drinking, ask the veterinarian how to proceed before giving the next dose. Do not add another NSAID or a corticosteroid on your own.<\/p>\n

Can a medicine that was tolerated well for years later become a problem?<\/h3>\n

Yes. A history of good tolerance is important and reassuring information, but it does not guarantee that the dog\u2019s risk will remain the same for life. Ageing, a new disease, dehydration, changes in kidney or liver function and the addition of other medicines can change the benefit-risk balance.<\/p>\n

That does not mean every kidney, liver or gastrointestinal disease that appears after three or six years was caused by the NSAID. It would be equally wrong to assume that years of problem-free use rule out a possible contribution from the medicine.<\/p>\n

There is therefore a major difference between saying \u2018we have no evidence that six years of treatment causes this problem\u2019 and \u2018we know that six years of treatment does not cause this problem\u2019. The first may be entirely correct. The second would require much stronger long-term data.<\/p>\n

What do \u2018rare\u2019 and \u2018very rare\u2019 mean?<\/h2>\n

In the EMA frequency categories for veterinary medicines:<\/p>\n