By Marc Brannigan and Natalie Mondine, co-founders of HempMy Pet · Published September 27, 2026 · Last reviewed October 17, 2026
We have grown, formulated and bottled full-spectrum hemp oil for pets on our own Colorado farm since 2016, and we funded two university clinical trials using our own oil. We are not veterinarians. Everything below about carprofen comes from published veterinary sources, which are listed at the end. It is not a reason to change your dog's prescription.
Rimadyl is one of the most prescribed drugs in veterinary medicine and one of the most searched-about. Owners look it up because someone in a forum said it damages livers, and they want to know whether they have just been handed something dangerous.
Here is the short answer, and it is not the one either side of that argument gives you.
Carprofen is the drug owners are most nervous about and, at the same time, the one with the best evidence that it actually works. In a randomized placebo-controlled trial it produced real, measurable improvement in arthritic dogs while another commonly prescribed painkiller did nothing.
The serious risk is real but uncommon, and it is idiosyncratic — it does not depend on dose and routine bloodwork does not reliably predict it. What protects your dog is knowing the three signs that mean stop and call, not avoiding the drug.
What Rimadyl Actually Is
Rimadyl is a brand name for carprofen, a non-steroidal anti-inflammatory drug (NSAID) approved for dogs. Generic carprofen and other brand names such as Novox and Vetprofen are the same active ingredient. Unlike gabapentin or tramadol, this one is FDA-approved for veterinary use, which means it went through a canine approval process rather than being borrowed from human medicine.
It works by inhibiting cyclooxygenase enzymes, with a preference for COX-2 over COX-1. In plain terms: COX-2 drives the inflammation and pain of an arthritic joint, while COX-1 does housekeeping work in the stomach lining and kidneys. Preferring COX-2 is how a modern veterinary NSAID gets the anti-inflammatory effect with less of the stomach damage older drugs caused. Preferring is not the same as ignoring, which is where the side effects come from.
Vets prescribe it for osteoarthritis and chronic joint pain, for post-surgical pain, and for soft-tissue injury.

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Does Carprofen Actually Work?
This matters more than it might seem, because the honest answer reframes the whole risk conversation. A drug with real benefit is worth a small risk. A drug with no benefit is not.
The cleanest evidence comes from a randomized, blinded, placebo-controlled crossover trial published in the Journal of the American Veterinary Medical Association. Forty dogs with arthritis of the elbow or stifle each received, in random order, ten days of placebo, ten days of carprofen, and ten days of tramadol. Researchers measured force-plate data — how much weight the dog actually put through the limb — alongside owner-scored pain inventories.
Carprofen significantly improved both the force-plate measures and the owner pain scores. Placebo did not. Tramadol did not either, and was statistically indistinguishable from the sugar pill.
That is an unusually clear result for a chronic-pain study, and it is worth holding onto when you read the risk section below.
The Common Side Effects
Most dogs tolerate carprofen well. When there is a problem, it is usually the digestive tract, and it usually shows up early.
- Vomiting and diarrhea — the most frequently reported effects, often in the first days or weeks.
- Reduced appetite — easy to dismiss, and the one worth taking most seriously (more on this below).
- Stomach ulceration — less common, and signalled by dark, tarry stool or vomit that looks like coffee grounds. That is an urgent call.
- Behaviour changes — lethargy, restlessness, or a dog that simply seems off.
- Changes in drinking and urination — which can point at the kidneys rather than the gut.
Giving the dose with food reduces the stomach upset for many dogs. It does not eliminate the risk, and it is not a substitute for telling your vet what you are seeing.
The Liver Question, Honestly
This is what people are really searching for, so here is the actual source rather than a forum summary of it.
In 1998, a case series in JAVMA described hepatocellular toxicosis in 21 dogs given carprofen. The presenting signs were consistent: anorexia, vomiting and jaundice. Bloodwork showed raised bilirubin and raised liver enzymes — ALT, ALP and AST. In seven of the nine dogs whose urine was tested, there were also signs suggesting kidney tubular involvement.
The part that usually gets left out of the scary version: most of those dogs recovered. Clinical signs resolved and the biochemistry improved or normalised once the drug was discontinued and supportive care given. The authors' own conclusion was not that the drug should not be used — it was that owners should be told what to watch for and instructed to stop immediately and call if they see it.
A later peer-reviewed review in Today's Veterinary Practice notes that idiosyncratic hepatotoxicity has been reported in Labrador retrievers in particular, with golden retrievers appearing in case reports as well, while being careful that causation in individual cases was not always certain. If you own a Lab, that is a reason to be attentive, not a reason to refuse the prescription.
The word that matters is idiosyncratic. It means the reaction is not dose-dependent and not predictable from the dog's history. It can happen at a normal dose in a dog with normal bloodwork. That is exactly why the practical advice below leans on what you can observe at home.
What Monitoring Actually Catches
Most vets recommend a blood panel before starting carprofen and periodic rechecks after, especially in older dogs and long-term users. That is good practice and you should do it. But it is worth understanding what it does and does not buy you.
What baseline and routine bloodwork is genuinely good at: finding the dog who should not start the drug in the first place (existing liver or kidney compromise), and catching the slow, dose-related drift that can happen over months of continuous use.
What it cannot do: predict an idiosyncratic reaction. A panel in March does not tell you what will happen in May. Because the reaction is unpredictable and can develop between scheduled rechecks, the thing that most changes the outcome is how fast the drug gets stopped once signs appear — and that depends on you, not the lab.
So the honest model is two layers. Bloodwork is the scheduled layer. Your own eyes are the continuous one.
When to Stop and Call
Do not wait for the next appointment if you see any of these. Stop the drug and contact your veterinarian.
- Your dog goes off food without an obvious reason, particularly in the first weeks.
- Repeated vomiting, or any vomit that looks like coffee grounds.
- Yellowing of the gums or the whites of the eyes. Check in daylight. This is a same-day call.
- Black, tarry or bloody stool.
- Marked lethargy, or a dog that is suddenly not itself.
- Much more or much less drinking and urinating than normal.
- Seizures, incoordination or collapse — emergency.
Stopping an NSAID abruptly is safe, unlike some other medications. If you are wrong and it was something else, you have lost a few days of pain relief. If you are right, you may have changed the outcome.
"Carprofen Killed My Dog": What Is Usually Behind It
Type that phrase into a search box and you will find threads full of grief, and a drug label that does not contradict them. The FDA-approved carprofen label states plainly that in post-approval reporting, death has been associated with some of the adverse reactions listed. We are not going to tell you those owners are wrong. Here is what the published record says about how it happens, because that is what lets you prevent it.
- The idiosyncratic liver reaction. This is the mechanism in the 21-dog case series above. It can happen at a normal dose, in a dog with normal bloodwork, typically in the first weeks. The paper describes the clinical course as variable: most dogs recovered once the drug was stopped, which also means not every dog did. The dogs who did worst were generally the ones where the drug kept going after appetite dropped and vomiting started.
- A perforated ulcer. NSAIDs thin the stomach's defences. An ulcer that bleeds shows up as black stool or coffee-ground vomit; one that perforates is a surgical emergency and can kill quickly. The risk climbs steeply when carprofen is combined with a steroid or a second NSAID, including aspirin an owner added on their own.
- Kidney injury in a dehydrated or already-compromised dog. NSAIDs reduce blood flow to the kidney. A dog who is vomiting, not drinking, or recovering from anaesthesia is the dog most likely to tip over.
- Something else entirely. Carprofen is prescribed to old dogs with painful joints, and old dogs die of many things. A dog who started Rimadyl two weeks before a collapse did not necessarily die of Rimadyl. That is not a dismissal; it is why a necropsy, when owners can face one, is sometimes the only way to know.
The common thread in the first three is time between the first sign and the last dose. Every one of them announces itself: appetite, vomiting, stool, drinking, gum colour. Stopping the drug the day you notice and calling your vet is what the case-series authors recommended in 1998, and nothing published since has changed it.
I Accidentally Gave My Dog a Double Dose of Carprofen
It happens constantly, usually because two people in the house each gave the evening tablet. Here is how to think about it, using the drug's own safety data rather than guesswork.
The labeled dose is 2 mg per pound per day (4.4 mg/kg), given once or split in two. In the FDA target-animal safety studies, healthy beagles were given three and five times that dose twice daily for 42 days with what the label calls no significant adverse reactions, apart from a couple of episodes of dark stool and one dog with a dip in blood albumin. At ten times the dose for two weeks, five of eight dogs had reddened duodenal lining and two had low albumin, but no actual ulceration on microscopy.
So for a healthy dog, one accidental double dose sits well inside the range the drug was tested at. That is the reassuring part. The less reassuring part is that those were young, healthy, well-hydrated beagles, and your dog is probably an older animal on the drug because something hurts. Do this:
- Call your vet or a poison line now, even if the dog looks fine. The ASPCA Animal Poison Control Center is (888) 426-4435 and is open around the clock. They will want the dog's weight, the tablet strength, how many, and when. Call sooner if your dog has kidney or liver history, is on a steroid or another NSAID, or got into the whole bottle rather than one extra tablet. Chewable carprofen tablets are flavoured, and a dog eating a bottle is the scenario that produces the kidney and GI emergencies.
- Skip the next scheduled dose unless your vet tells you otherwise, and make sure water is freely available.
- Watch for 72 hours: vomiting, refusing food, black or bloody stool, lethargy, and any change in how much the dog drinks or urinates. Any of those is a same-day visit.
- Do not induce vomiting at home with hydrogen peroxide unless a vet or poison line tells you to. It is often the wrong call for an NSAID and can cause its own damage.
Then fix the thing that caused it: one person owns the pill, or a weekly pill box, or a tick on the calendar. Most double doses are a communication problem, not a carelessness problem.
Which Dogs Should Not Take Carprofen
- Dogs with existing liver or kidney disease, or known NSAID sensitivity.
- Dogs with a history of stomach ulcers or gastrointestinal bleeding.
- Dogs on corticosteroids such as prednisone — combining a steroid and an NSAID substantially raises ulcer risk. This combination is a genuine contraindication, not a caution.
- Dogs on another NSAID. Never stack them, and observe the washout period your vet specifies when switching.
- Dehydrated dogs, or dogs around anaesthesia, where kidney perfusion is already under pressure.
- Pregnant, nursing or very young dogs, where safety is not established.
- Never give human NSAIDs — ibuprofen, naproxen, aspirin — as a substitute. They are considerably more dangerous to dogs than carprofen is, and this is one of the more common ways owners cause the harm they were trying to avoid. We set out the exact doses that harm, tablet by tablet, in what you can and cannot give a dog for pain.
Giving It Safely: The Practical Part
- Get baseline bloodwork before the first dose — a chemistry panel covering liver and kidney values.
- Give it with food, at the same times each day. Consistency matters for an anti-inflammatory.
- Use the lowest dose that works. The label range allows flexibility; ask whether your dog can sit at the lower end, especially long term.
- Watch closely for the first two weeks, and write down appetite, stool and energy. Most problems declare themselves early.
- Recheck bloodwork at two to four weeks after starting, then at the interval your vet sets — commonly every six months for long-term use, more often in senior dogs.
- Never double a missed dose, and never share a prescription between pets.
- Reassess periodically. A dog whose weight and activity have changed may need a different amount than the one prescribed a year ago.
Rimadyl Dosage by Weight: How the Dose Is Calculated
Carprofen is one of the few drugs in this series with an FDA-approved canine label, so the dose is not a matter of opinion. The Rimadyl label on DailyMed gives it as 2 mg per pound of body weight per day (4.4 mg/kg), either as one dose of 2 mg/lb once daily or split into 1 mg/lb twice daily. The chewable tablets come in 25 mg, 75 mg and 100 mg, are scored, and the label says to calculate the dose in half-tablet steps. For post-surgical pain, the label says to give it about two hours before the procedure.
The table below uses those figures. The last two columns come from Zoetis's own Rimadyl dosing chart, which assigns each weight band a tablet. Because tablets only split in halves, the real dose lands a little above or below 2 mg/lb depending on where your dog sits inside a band.
| Dog weight | Label daily total (2 mg/lb) | Or split dose | Zoetis chart, once daily | Works out to |
|---|---|---|---|---|
| 10 lb (4.5 kg) | 20 mg | 10 mg twice daily | ½ × 25 mg = 12.5 mg | 1.25 mg/lb |
| 20 lb (9.1 kg) | 40 mg | 20 mg twice daily | ½ × 75 mg = 37.5 mg | 1.88 mg/lb |
| 40 lb (18.1 kg) | 80 mg | 40 mg twice daily | 1 × 75 mg = 75 mg | 1.88 mg/lb |
| 60 lb (27.2 kg) | 120 mg | 60 mg twice daily | 1 × 100 mg = 100 mg | 1.67 mg/lb |
| 80 lb (36.3 kg) | 160 mg | 80 mg twice daily | 1½ × 100 mg = 150 mg | 1.88 mg/lb |
| 100 lb (45.4 kg) | 200 mg | 100 mg twice daily | 2 × 100 mg = 200 mg | 2 mg/lb |
Calculated from the 2 mg/lb label dose. Chart tablets from the Zoetis Rimadyl dosing chart (weight bands 5–10, 11–15, 16–20, 21–30, 31–40, 41–60, 61–90, 91–120 lb). Rounded to half-tablets as the label directs.
Your veterinarian sets the dose. This table shows how the published figure is calculated so you can check the arithmetic and ask better questions, not so you can dose without a prescription. Never give a human tablet to your dog without your vet telling you to. The label's own instruction is to use the lowest effective dose for the shortest duration consistent with your dog's response, so many vets prescribe below 2 mg/lb once a dog is comfortable. Never give ibuprofen, naproxen or aspirin in place of it; human NSAIDs are far more dangerous to dogs.
Once a day or twice? Morning or night?
The label allows either. Carprofen's mean half-life in dogs is about 8 hours (range 4.5–9.8 hours) after a single oral dose, with peak blood levels 1–3 hours after the tablet. If your vet splits it, give the two halves about 12 hours apart. The label does not prefer morning or night; what matters is the same time every day, given with a meal if it upsets your dog's stomach, and one person in the house owning the pill so it is never doubled.
Generic carprofen, Vetprofen and the same dose
Generic carprofen and other brands carry the same active ingredient. The Vetprofen label gives the same 2 mg/lb (4.4 mg/kg) daily dose and the same 25, 75 and 100 mg tablet sizes, so a switch between brands should not change the number of milligrams. Check the strength on the new bottle before the first dose: a 75 mg tablet from one brand and a 100 mg tablet from another look alike in a pill box.
Too much, and when to call
In the label's safety studies, healthy beagles given 10 times the daily dose for 14 days developed low albumin in 2 of 8 and reddened duodenal lining in 5 of 8. The accidental-double-dose steps are set out in the section above. If your dog ate several tablets or the bottle, or has kidney or liver disease, call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 (open 24 hours; a consultation fee may apply) now. Watch for vomiting, refusing food, black or tarry stool, yellow gums and changes in drinking. Carprofen is often paired with or swapped for Galliprant; never give the two together.
Can My Dog Take Carprofen and Gabapentin Together?
Yes, and this is one of the most common pain combinations in veterinary practice. It is worth understanding why it is allowed when carprofen plus aspirin is not.
The carprofen label warns against combining it with other anti-inflammatory drugs: other NSAIDs and corticosteroids. Those drugs act on the same pathways, so stacking them stacks the stomach and kidney risk. Gabapentin is not an anti-inflammatory. It works on nerve signalling, is cleared mainly by the kidneys rather than the liver, and does not touch the COX enzymes at all. The two drugs cover different kinds of pain, which is the whole point of what vets call multimodal analgesia.
The combination has been studied directly. A 2023 randomized trial in Veterinary and Comparative Orthopaedics and Traumatology gave 20 dogs recovering from knee surgery either carprofen alone or carprofen plus gabapentin for 14 days. No adverse events were recorded in either group. The gabapentin did not measurably improve pain scores in that study, which is a fair reminder that adding a drug is not automatically adding benefit, but the safety of the pairing was not the issue.
Practical notes if your dog is on both: gabapentin's main side effect is sedation and wobbliness, especially in the first days, so a dog who is suddenly sleepy and unsteady is almost certainly feeling the gabapentin rather than the carprofen. Loss of appetite and vomiting, on the other hand, point at the NSAID and should be treated as a stop-and-call. We cover the gabapentin side in gabapentin for dogs: side effects and what to watch.
How Long Can a Dog Stay on Carprofen?
As long as it keeps working and the bloodwork keeps allowing it. There is no label limit on duration, and dogs with osteoarthritis commonly take it for years. The 52-week safety study behind the label found no gross or microscopic organ changes in dogs given up to 5.7 times the labeled dose for a full year.
What changes over long-term use is the monitoring rhythm, not the drug. A sensible pattern, which you should confirm with your own vet:
- Baseline chemistry panel before the first dose.
- Two to four weeks in, a recheck. This is the window where the idiosyncratic reaction usually shows if it is going to.
- Every six months after that for a dog doing well; every three to four months for a senior dog, a dog with borderline kidney values, or a dog on the upper end of the dose range.
- Any time appetite, drinking, stool or energy change, regardless of the schedule.
Long-term use is also where the lowest-effective-dose question matters most. Some dogs do well on every-other-day dosing or a reduced daily amount once the inflammation is controlled, and the trial-and-reduce conversation is one to have with your vet at each recheck rather than refilling the same prescription on autopilot.
Reducing What the Drug Has to Carry
Carprofen is one part of a joint plan, not the whole of it. The parts that reduce how much work the drug has to do are unglamorous and well evidenced:
- Weight. Every extra pound loads an already sore joint. This is the single highest-value thing most owners can change.
- Low-impact movement. Short, frequent walks and swimming beat weekend sprints.
- Traction at home. Rugs on hard floors, ramps instead of jumps.
- Omega fatty acids and joint support as part of a daily routine.
Our full guide to hemp and CBD oil for dogs with joint discomfort covers how these fit together, and the early signs and real stages of arthritis in dogs is worth reading if your dog is only just starting to slow down.
Can Hemp Be Given Alongside Carprofen?
This is the question we get most often on this drug, so here is the careful answer rather than the convenient one.
There is no documented pharmacokinetic interaction between CBD and carprofen published in dogs. The canine enzyme research that has been done flagged tramadol, not NSAIDs. So the concern is not that one drug changes the level of the other.
The real reason to be deliberate is simpler: both are handled by the liver, and both can move liver values. If your dog's ALP rises three months in, you want to be able to tell your vet which substance to suspect — and that is only possible if you started from a baseline and changed one thing at a time. We went through the canine enzyme and liver-enzyme literature drug by drug in our guide to CBD and your dog's medications.
For what it is worth on the joint side: in our own 90-day university trial of 37 dogs with chronic joint discomfort, 23 were taking gabapentin at enrollment and, by the end, 10 had discontinued it and 11 had reduced their dose — every change made by that dog's own veterinarian. That trial did not test carprofen reduction, and we are not going to imply that it did. Whether hemp has a place alongside your dog's NSAID is a conversation for your vet, who can order the bloodwork that makes it a safe experiment rather than a guess.
Full-spectrum extract, grown and bottled on our own Colorado farm — the same oil given to the 37 dogs in the 90-day study. Third-party tested, Certificate of Analysis in every order. $99
Shop the 1000mg Oil → See the StudyQuestions Worth Asking Your Vet
- Can we start at the lower end of the dose range, and is that realistic for my dog?
- When do you want the first recheck panel, and what would make you want it sooner?
- Given my dog's breed and age, is there anything that makes you more cautious here?
- If my dog goes off food on a Saturday, do you want me to stop the drug and call Monday, or call the emergency line?
- What else in the plan — weight, activity, supplements — could let us use less of this over time?
Related: Carprofen for Dogs
Frequently Asked Questions
What are the most common side effects of Rimadyl in dogs?
Digestive upset — vomiting, diarrhea and reduced appetite — is the most frequently reported, usually early in treatment. Serious liver and kidney effects are uncommon but are the reason monitoring is recommended. Giving the dose with food helps with the stomach upset for many dogs.
Is Rimadyl bad for a dog's liver?
For most dogs, no. The concerning reaction is idiosyncratic hepatotoxicity, which is uncommon, not dose-dependent, and not reliably predicted by bloodwork. In the published case series of 21 affected dogs, most recovered once the drug was stopped and supportive care given. That is why the practical advice is to know the signs — loss of appetite, vomiting, yellow gums or eyes — and stop immediately if they appear.
Does carprofen actually work for dog arthritis?
Yes, and the evidence is better than for most options. In a randomized, blinded, placebo-controlled crossover trial in 40 arthritic dogs, carprofen produced significant improvement in both force-plate measures and owner pain scores, while placebo and tramadol did not.
How long can a dog stay on Rimadyl?
Many dogs take it for years under veterinary supervision. Long-term use is normal for osteoarthritis; what makes it safe is periodic bloodwork, using the lowest effective dose, and reassessing rather than refilling indefinitely without review.
What should I do if my dog stops eating on carprofen?
Stop the drug and call your veterinarian. Loss of appetite was the most common first sign in the published liver-injury case series, and stopping an NSAID abruptly is safe. If it turns out to be unrelated, you have lost a couple of days of pain relief.
Can I give my dog CBD or hemp oil with Rimadyl?
Ask your veterinarian first. There is no documented drug-level interaction between CBD and carprofen published in dogs, but both are processed by the liver and both can move liver values, so baseline bloodwork and changing one thing at a time is what makes it interpretable.
Can I give my dog ibuprofen or aspirin instead?
No. Human NSAIDs are considerably more dangerous to dogs than veterinary-approved ones, and substituting them is a common cause of serious harm. If cost is the issue, ask about generic carprofen rather than a human drug.
Which dogs should not take carprofen?
Dogs with existing liver or kidney disease, a history of stomach ulcers, known NSAID sensitivity, or dogs taking corticosteroids or another NSAID. Dehydrated dogs and pregnant or nursing dogs are also excluded. Labrador retrievers appear more often in the idiosyncratic hepatotoxicity case reports, which is a reason for attentiveness rather than avoidance.
Can carprofen kill a dog?
Rarely, yes. The FDA label acknowledges that death has been associated with some reported adverse reactions. The usual routes are an idiosyncratic liver reaction, a perforated stomach ulcer (most often when combined with a steroid or another NSAID), or kidney injury in a dehydrated or already-compromised dog. All three announce themselves first through appetite, vomiting, stool or drinking changes, and stopping the drug at the first sign is what changes the outcome.
What should I do if I accidentally gave my dog a double dose of carprofen?
Call your vet or a pet poison line now, skip the next scheduled dose unless told otherwise, keep water available, and watch for 72 hours for vomiting, refusing food, black or bloody stool and changes in drinking or urination. In the drug's safety studies, healthy beagles tolerated three to five times the labeled dose for six weeks without significant adverse reactions, so a single double dose in a healthy dog is usually not an emergency, but an older dog, a dog with kidney or liver history, or a dog that ate the whole bottle is a different situation.
Can my dog take carprofen and gabapentin together?
Yes, under veterinary direction. The combination is routine because the drugs work by different mechanisms: carprofen is an anti-inflammatory and gabapentin acts on nerve signalling, so they do not stack the stomach and kidney risk that two NSAIDs would. A 2023 randomized trial of the pairing in 20 dogs recorded no adverse events. The combination you must avoid is carprofen with a steroid or another NSAID.
Does Rimadyl cause drowsiness in dogs?
Not as a direct effect. Carprofen is an anti-inflammatory, not a sedative, so it should not make a dog sleepy the way gabapentin or trazodone does. Two things can look like drowsiness, though. A dog whose joint pain has eased often sleeps more and better in the first week, which is the drug working, not a side effect. Lethargy and behaviour change are also listed adverse reactions, usually mild and early. The distinction that matters: a dog who is drowsy and off food, vomiting, or showing yellow gums is not sleepy, it is showing the early signs of the liver reaction, and that is a stop-and-call. If your dog is on carprofen with gabapentin, sudden sleepiness and wobbliness almost always belong to the gabapentin.
How much Rimadyl can I give my dog?
The FDA-approved label dose is 2 mg per pound of body weight per day (4.4 mg/kg), given once daily or split into 1 mg/lb twice daily. For a 40 lb dog that is 80 mg a day; the Zoetis chart rounds it to one 75 mg tablet. Your veterinarian sets the actual dose, often lower once the dog is comfortable.
Is 75 mg of carprofen a lot for a dog?
It depends on weight. At the label dose of 2 mg/lb a day, 75 mg is the full daily amount for a dog of about 37.5 lb, and the Zoetis chart uses one 75 mg tablet for dogs of 31 to 40 lb. For a 20 lb dog, 75 mg would be nearly twice the label dose, which is why the chart gives that dog half a tablet.
Is it better to give a dog Rimadyl in the morning or at night?
The label does not prefer either. It allows the whole dose once a day or half the dose twice a day, about 12 hours apart. Carprofen has a half-life of about 8 hours in dogs. Pick a time you will keep every day, give it with food if it upsets the stomach, and have one person in charge of it so it is never doubled.
Is Vetprofen the same as carprofen?
Yes. Vetprofen is a brand of carprofen, like Rimadyl. Its label gives the same 2 mg/lb daily dose and the same 25, 75 and 100 mg tablet sizes. Check the strength on any new bottle before giving the first dose.
The same full-spectrum oil that went through two university clinical trials. Start low, go slow, and tell your veterinarian what you are giving.
How We Sourced This Article
Every claim above traces to one of these.
- Budsberg SC, Torres BT, Kleinhenz SN, et al. Lack of effectiveness of tramadol hydrochloride for the treatment of pain and joint dysfunction in dogs with chronic osteoarthritis. J Am Vet Med Assoc. 2018;252:427–432. PubMed. Source for the efficacy comparison between carprofen, tramadol and placebo.
- MacPhail CM, Lappin MR, Meyer DJ, et al. Hepatocellular toxicosis associated with administration of carprofen in 21 dogs. J Am Vet Med Assoc. 1998;212:1895–1901. PubMed. Source for the presenting signs, the biochemistry, the renal findings and the recovery on discontinuation.
- Today's Veterinary Practice — Carprofen for Dogs: Osteoarthritis and Pain Management. Peer-reviewed review; source for COX-2 selectivity, the adverse-effect profile and the breed case reports.
- American Kennel Club — Rimadyl (Carprofen) for Dogs. Owner-facing overview of uses and monitoring.
- Norbrook Laboratories — Carprieve (carprofen) caplets, FDA-approved package insert. Source for the labeled dose, the target-animal safety studies at 1x, 3x, 5x and 10x dose, the 52-week study, the post-approval death statement and the concomitant-drug precautions.
- Evaluation of Gabapentin in the Treatment of Postoperative Pain after a Tibial Plateau Levelling Osteotomy in Dogs. Vet Comp Orthop Traumatol. 2023. DOI 10.1055/s-0042-1751069. Source for the carprofen-plus-gabapentin randomized trial and its safety outcome.
- Court MH, et al. Cannabidiol and cannabidiolic acid: Preliminary in vitro evaluation of drug–drug interactions involving canine cytochrome P-450. J Vet Pharmacol Ther. 2024;47:1–13. PubMed. Source for which drug the canine enzyme work actually flagged.
- Kogan L, Hellyer P, Downing R. The Use of Cannabidiol-Rich Hemp Oil Extract to Treat Canine Osteoarthritis-Related Pain: A Pilot Study. J Am Holist Vet Med Assoc. 2020;58:35–45. DOI 10.56641/UPRM3253. Our disclosure: HempMy Pet supplied the hemp extract and reimbursed clinic costs; per the journal we had no input into study design or interpretation.
If you find something here that conflicts with your veterinarian, email us at support@hempmypet.com and we will correct it.
These statements have not been evaluated by the Food and Drug Administration. Our products are not intended to diagnose, treat, cure, or prevent any disease. This article is educational and is not veterinary advice. Carprofen is a prescription medication — never start, stop, or change your dog's dose without your veterinarian.

