What’s the lowdown about aspirin and dogs?
Whether you have an active dog that gets the occasional sprain or an older dog that’s stiff when it rains, there are times when your canine companion could benefit from pain relief.
No one wants to be constantly running to the vet’s for minor problems, so this need may prompt you to look through your medicine cabinet and wonder, “Can I give my dog aspirin?”
The short answer to this question is, “Yes you can, but with care.”
But be sure to read the whole article before dosing your dog, so you are aware of the dangers as well as the benefits of giving aspirin to dogs.
Let’s start at the beginning by understanding more about aspirin.
Aspirin has been around for a long time, since 1893 in fact.
The active ingredient, acetyl salicylic acid, was originally derived from willow bark which was an even older remedy used to bring down fever.
Despite aspirin being over 100 years old, it was only in 1972 that scientists discovered how it worked to relieve pain and reduce inflammation.
It turns out that aspirin inhibits chemicals in the body called prostaglandins, which are responsible for a vicious circle of inflammation.
By blocking prostaglandins the pathway that leads to pain is blocked, hence aspirin’s anti-inflammatory, anti-fever, and pain relieving properties.
Aspirin is in fact the founder member of an important group of modern painkillers called the non-steroidal anti-inflammatory drugs (NSAIDs) Indeed many of the state-of-the-art painkillers that are currently licensed for use in dogs belong to this family of drugs.
Aspirin is a bit of a blunt instrument compared to modern NSAIDs, hence why it is rarely prescribed by vets these days.
This means that although it has aspirin does have its uses, it’s not as safe as other drugs and can cause some nasty side effects (or even death) when used inappropriately.
The actions aspirin has include those of being:
This makes it a useful option for short term use, because side effects are related to both the dose and the length of treatment.
Aspirin also best suited to treat mild to moderate pain, but is unlikely to impact on severe discomfort.
Aspirin is mainly used to the occasional sprain, mild arthritis, or to reduce the risk of blood clots (the latter under supervision and only as prescribed by your vet.)
But before reaching for that bottle of aspirin, be sure your dog is not in a group that should NOT be given it.
Before even thinking about the dog aspirin dose it’s important to be sure it is safe for your dog.
Because of the relative lack of sophistication of how aspirin works, there are many dogs for which this medication is NOT suitable.
Aspirin is broken down and got rid of by the liver, so a weakened liver is not able to detox the blood effectively and the levels of aspirin rise with each subsequent dose.
High levels of aspirin (through overdose, liver disease, or dehydration) damage and kill kidney cells, potentially sending the dog into kidney failure.
Aspirin also works by inhibiting prostaglandin release.
But do you remember how we said aspirin is a blunt instrument?
This is because not all prostaglandins are bad, and some serve useful purposes such as maintaining the blood supply to the kidneys and producing a protective mucus lining in the stomach.
This means that as well as desirable actions such as relieving pain, aspirin has less welcome actions such as decreasing the blood to the kidney and weakening the stomach lining leading to potentially dangerous and life-threatening ulcers.
This is where the modern NSAIDs prescribed by your vet have the edge.
These drugs as highly targeted and which means they have more benefits and fewer drawbacks than aspirin, making them a safer option.
That bottle of aspirin in your medicine cabinet is designed for people, who are many times heavier than the average pet dog.
This leads to the most obvious danger which is giving a human dose to a dog and a relative overdose.
Since the side effects are dose related, this is a common cause of serious problems.
Another problem is that human products, such as cold or flu remedies, contain active ingredients in addition to aspirin – many of which are not safe for dogs (such as acetoaminophyline.)
So even if you get the aspirin dose correct, the dog may still be at risk of overdose or side effects.
A third complication is dangerous drug interactions.
An example of this is giving aspirin to the dog who takes steroid for his itchy skin, this amplifies the ulcerative action of both drugs and could lead to life-threatening internal hemorrhage.
A fourth problem is the dog who consumes hidden aspirin by accident, when it is present in other medications.
Products such as Pepto-Bismol and Kaopectate contain aspirin as an active ingredient, and so if your dog takes these whilst on other meds he could be on a collision course with trouble.
Long story short, if in doubt speak to the vet before giving your dog aspirin.
Before giving aspirin to your dog weigh up these three important considerations:
But if you still decide to go ahead, let’s look at the recommended aspirin dosage for dogs.
The average recommended dose of aspirin for dogs is 10 mg / kg.
This means that a 10kg dog takes just 100mg of aspirin.
Most household aspirins are 300mg, which means giving the dog a maximum dose of one-third of a tablet, twice a day.
The bigger problem lies with smaller dogs. Consider a 4 kg Yorkie and you start to see a problem.
A cutie like this requires 40mg maximum, which is equivalent to just over one-tenth of a tablet – and super easy to overdose.
To reduce the risk of accidental overdose be sure to use either children’s aspirin (typically 75 – 80 mg each) or canine aspirin (100mg per tablet) which makes giving small doses much easier.
Also, always give aspirin with or after food, which then acts as a barrier to protect the stomach from aspirin induced ulceration.
Aspirin toxicity occurs from around the 30mg / kg body weight dose.
Thus giving a single 300mg aspirin to a 10kg dog is considered dangerous.
If your dog has an overdose, then contact your vet immediately.
They may need to stomach pump your dog to remove any aspirin residue, and give intravenous fluids to support organ function.
They may also prescribe activated-charcoal to mop up any aspirin in the gut, plus give medications to protect the lining of the stomach from ulceration.
In short, if your dog has a sprain or a painful joint, yes you can give aspirin: but it needs to be with care and only given for short times.
Also, your dog must be otherwise fit and healthy dogs, and not dehydrated.
If in doubt contact your vet for advice before making a potentially dangerous mistake.
It is better to double check when trying to relieve your pet’s discomfort, than make the situation worse by dosing inappropriately with aspirin.
Dr Sarah Robinson attended veterinary school at Oklahoma State University receiving a D.V.M. in 2008. Sarah’s longtime interest is to help people to better communicate with their pet companions, and in doing so, to help them to strengthen their relationships with their dogs and cats. Sarah has published numerous articles on canine feeding in pet related magazines, veterinary journals and leading natural health web sites.