The bottle of ibuprofen is already in your hand. He came back from this afternoon’s walk stiff, and tonight he stood at the bottom of the stairs and didn’t try them. You’ve read the back of the bottle twice. There’s a line for adults and children 12 years and over, then one for children under 12: ask a doctor. There is no line for a 60-pound dog, so you start working one out from the lines that are there.
It’s how almost anyone would reason, and it treats him as a small person, which a dog isn’t. Nothing from that bottle, or from the others in the house, goes into him unless his vet says so.
If he has already swallowed some, skip to What if he already swallowed some? below.
Quick answer
Can you give a dog ibuprofen, Tylenol, Aleve or aspirin? Not on your own. These drugs can harm his stomach, kidneys or liver, and stomach damage can happen without obvious signs. Which painkiller he can have, if any, is for his vet to decide, so call your clinic and ask about pain relief made for dogs. Already swallowed some? Don’t wait for signs: phone your vet or a pet poison line now.
Why can’t a dog take what I take?
Because his body handles most of these drugs differently from yours. The FDA’s guide for pet owners lists four ways a human anti-inflammatory can behave in a dog: it may last longer, be processed differently, be absorbed faster and reach higher levels in the blood (FDA). None of those four is about his size, so shrinking a person’s dose doesn’t fix them.
Ibuprofen, naproxen and aspirin all work by cutting down prostaglandins, the chemical messengers that help drive pain and inflammation. The same messengers help protect the lining of the stomach and keep blood flowing to the kidneys (FDA). Block them, and the protection goes down along with the pain.
Even the anti-inflammatories made for dogs can strain the kidneys and liver, which is why the FDA suggests blood tests to check both before a dog starts one long term, and again along the way (FDA).
The harder part is that the damage can be quiet. Dogs can have stomach and intestinal ulcers without showing signs (FDA), and the Merck Veterinary Manual notes that well-meaning owners often give their pets a human anti-inflammatory without recognizing the mistake until signs of illness appear (Hovda, Merck Veterinary Manual). Pain in a dog is hard enough to read when it shows. An ulcer may not show at all.
What about ibuprofen, Tylenol, Aleve or aspirin?
Each of the four can harm a dog, and each in its own way.
Ibuprofen (Advil, Motrin)
The Merck Veterinary Manual says ibuprofen is no longer recommended for dogs, because it may cause stomach ulcers and perforations, and it describes its margin of safety in dogs as narrow (Hovda, Merck Veterinary Manual). A large single amount can bring on kidney failure, and a very large one can be fatal.
The stomach needs much less: the manual records dogs developing stomach ulcers or erosions within 30 days on a daily dose far below the amounts that cause acute poisoning (Hovda, Merck Veterinary Manual).
Acetaminophen (Tylenol)
Acetaminophen isn’t an anti-inflammatory, so it works differently from the other three. In dogs, the organ it threatens most is the liver (FDA). A single large amount can do that damage, and so can repeated smaller ones: the manual notes that toxicity can occur at lower doses when the exposure is repeated (Hovda, Merck Veterinary Manual).
Vets do sometimes use it for pain in dogs (FDA). That is why the decision is theirs. Whether it suits your dog, at what dose, and alongside what else he takes gets decided in the exam room, not from the bottle.
Naproxen (Aleve)
Naproxen is the one that stays. A dog’s body takes days to clear it (Hovda, Merck Veterinary Manual). In the dog cases the manual describes, a daily dose for three days or a week brought on vomiting and black, tarry stool from bleeding in the gut, and in one case a single larger dose did the same. One dog also had pale gums and weakness.
Aspirin
Aspirin is an anti-inflammatory, and with repeated use it can ulcerate a dog’s stomach. In small studies, many of the dogs given repeated doses developed stomach erosions or ulcers within days to weeks. It also interferes with clotting, so bleeding can be harder to stop (Hovda, Merck Veterinary Manual).
You may see chewable aspirin sold for dogs in pet stores and online. According to the FDA, no over-the-counter anti-inflammatory is approved for dogs, and one sold without a vet’s prescription is an unapproved animal drug that the agency has not reviewed (FDA). Whatever the package says, aspirin is his vet’s call, the same as the other three.
He’s already on something from the vet. Can I add to it?
Ask your vet first. Two anti-inflammatories, or an anti-inflammatory and a steroid such as prednisone, raise the risk to the stomach and intestines, and the FDA says they should not be given at the same time (FDA). If your dog already takes a prescribed anti-inflammatory, an aspirin on top for a bad day is that combination. Don’t add it.
The same goes for a leftover prescription from another dog in the house. The dose on that label was set for that dog, and the FDA warns that a medicine meant for your other dog may not be right for this one and may even hurt him (FDA).
These drugs also turn up in other boxes. Acetaminophen and some anti-inflammatories are in many cough and cold products (Hovda, Merck Veterinary Manual), so a dog can get a painkiller from a box that looks like it’s for something else.
What if he already swallowed some?
Call now, while he still seems fine: your vet, an emergency clinic, or an animal poison line. Two poison lines answer around the clock, and both can charge a consultation fee: ASPCA Poison Control at (888) 426-4435 and Pet Poison Helpline at (855) 764-7661.
Don’t try to make him vomit unless the vet or the poison line tells you to (Pet Poison Helpline).
Have the package in your hand when you call: the drug, the strength, roughly how many, when, and about what he weighs. The people on the line use those details to work out whether he can be watched at home or needs to be seen (Pet Poison Helpline). The exact product matters too, since a cough or cold medicine can carry acetaminophen or an anti-inflammatory in its ingredient list (Hovda, Merck Veterinary Manual).
If you gave it to him yourself, you’re far from the first. Pets end up with human painkillers both ways, by accident and from owners trying to help, and those cases reach animal poison control centers every day, with dogs the species most often involved (Hovda, Merck Veterinary Manual).
Caught early and treated properly, these cases generally go well, but how well depends on which product it was, how much, and how soon treatment starts (Hovda, Merck Veterinary Manual). That last part is the reason to call before he looks sick.
What can I do for him instead?
Call your clinic today, and if it’s closed, an emergency clinic. Tell them what you’re seeing and ask whether he needs to be seen right away or can wait for an appointment. A few notes on when he’s stiff and what he’s stopped doing help them decide.
In the same call, ask about pain relief made for dogs. The anti-inflammatories approved for dogs are available only by a vet’s prescription (FDA), and there are other options beyond them, each with its own questions worth asking. Sometimes a vet will treat the pain and watch what changes, which can help show how much of what you’re noticing is pain.
Until then, keep him quiet and comfortable, and let him skip the stairs.
What should I keep handy, just in case?
Two phone numbers. Before you close this page, save them in your phone: ASPCA Poison Control, (888) 426-4435, and Pet Poison Helpline, (855) 764-7661. With luck you’ll never need them. If you ever do, the call takes seconds instead of a search.
The bottle goes back where it came from, and tonight he stays downstairs. Its label was never going to have a line for him. The one that does will come from your vet, with his name on it.
Common questions
Is one tablet enough to hurt a dog?
It can be, and there’s no way to judge it from home, which is reason enough not to give one. If he has already had one, that judgment is what ASPCA Poison Control and Pet Poison Helpline make when you call, so call rather than wait.
Can I give him an extra dose of the pain medicine his vet prescribed?
Not without asking his vet first. The FDA’s advice for dogs on a long-term anti-inflammatory is to always talk to your veterinarian before adjusting the dose, especially before increasing it. If he still seems sore, the clinic that prescribed it is the one to call; ask what else can be done.
Is there a safe dose I can look up?
No. Only his vet can weigh whether he should have any of these at all, and how much, after looking at his stomach, his kidneys and liver, and any other medicine he’s on. The FDA asks owners to tell the vet about other medicines and any past stomach or intestinal problems before an anti-inflammatory is started, and the Merck Veterinary Manual records harm from repeated low doses as well as large single ones.
Sources
- ASPCA Poison Control. Link
- Hovda T. Toxicoses From Human Analgesics in Animals. Merck Veterinary Manual (Professional Version), full review Jul 2024, last updated May 2025. Link
- Pet Poison Helpline. Link
- U.S. Food and Drug Administration. Get the Facts about Pain Relievers for Pets. Content current as of 09/29/2022. Link