Milk Thistle For Dogs

milk thistle for dogs

Milk thistle for dogs is becoming a common mainstream treatment for liver problems, bowel disorders, and cancer treatments. Side effects to milk thistle for dogs can include diarrhea and stomach upsets. So, keep a close eye on your pup if you choose to give them this treatment.

The correct dosage will vary depending on the size and weight of your dog. And, it’s important to follow your veterinarian’s advice about treatment and dosage. They may suggest different dosages depending on the illness milk thistle is treating.

Milk Thistle for Dogs Quick Links

Offering your dog any new treatment or medication can come with as many risks as benefits. It’s natural that you’ll want to learn everything you can about milk thistle before giving it to your Lab. Here are a few quick links to everything we will cover in this guide.

Let’s start things off by finding out a little more about what milk thistle is, and how common it is as a treatment.

What is Milk Thistle for Dogs?

Milk thistle is a herbal treatment. It is often used in humans to treat liver problems and more. It is derived from the milk thistle plant, also known as Silybum Marianum. The active ingredient of milk thistle is silymarin. This is a flavonoid most often found in the seeds of the plant. This flavonoid has potentially beneficial antioxidant qualities, which is what can help our dogs with certain health issues.

Milk thistle has been a popular herbal remedy with holistic veterinarians for years. But there are very few scientific studies that research the efficacy of the treatment. So, let’s take a closer look at what milk thistle is meant to treat in dogs. And whether the risks outweigh the potential benefits.

What is Milk Thistle Good for in Dogs?

Milk thistle has been treating human health issues and preventing problems for potentially thousands of years. Studies have also researched the effectiveness of milk thistle for human diseases. But, what about in dogs?

milk thistle for dogs

Unfortunately, there are fewer studies for us to refer to when researching milk thistle for dogs. But, this doesn’t mean that it definitely won’t help with any health issues. It just means there is less evidence around its side effects and its actual effectiveness.

Proponents of milk thistle for canines believe it can help to treat issues like:

  • Amanita intoxication (a type of toxic fungus, such as death cap)
  • Renal failure
  • And liver problems.

Milk Thistle for Dogs’ Livers

In humans, milk thistle is a great choice to help with liver issues. And, some studies have found similar effects in dogs. Research is ongoing about milk thistle as a treatment for liver problems, among other health issues in dogs. But, it is becoming a more common treatment. Even with non-holistic veterinarians.

For some dogs, milk thistle could help with liver problems. But, for others it may have no effect. So, it’s important to speak to your vet about the most recent research. And about whether it could be useful for your dog’s specific situation. If it’s something you want to try, it’s always best to do under your vet’s guidance.

Milk Thistle Dosage for Dogs

The correct dosage of milk thistle for your dog will depend on your dog’s breed and size. Small dogs will need much smaller doses of medication than larger dogs.

Will I Need a Prescription?

Generally, milk thistle is taken in an oral form. Capsules are the most common form. But you must make sure you are choosing the correct size. You won’t need a prescription for milk thistle. But, some pharmacies and vets also sell it in liquid form.

Check the Packaging

The amount of milk thistle per capsule, or even per recommended dose on the packaging will vary from one brand to the next. So, it’s important to run it past your vet.

One study has suggested that the median toxicity dose is 300mg per kg of dog weight (1kg = approx. 2.2 pounds). But, your veterinarian will be best placed to advise you on the right dose for the milk thistle treatment you have chosen.

Can I Give My Dog Milk Thistle for Humans?

Generally, it’s best not to give your dog milk thistle capsules designed for humans. Unless your vet has given them their approval, of course. Some manufacturers will add extra ingredients to human medication that is not safe for dogs. So, you should always check the ingredients before giving anything to your dog.

On top of this, humans are much larger than dogs. So, the dosage in a capsule of milk thistle medication for humans could be much too large for your dog. Particularly if you have a small breed. It’s best to either choose a milk thistle capsule made specifically for dogs, or to run it past your veterinarian.

How to Give Milk Thistle to Dogs

As we’ve already learnt, milk thistle is best taken orally. Generally, it will come in capsule form. But it may also be available to you in liquid form. If your vet has recommended this treatment for your dog, they may suggest liquid form is best. Particularly if your dog does not like taking tablets. But, if you are using capsules, you can hide one in your dog’s food. Or wrap it in some ham to disguise it as a tasty treat.

Remember, do not exceed the dosage that your veterinarian has recommended. This could lead to bad side effects or toxicity in extreme cases.

Milk Thistle for Dogs – Side Effects

Studies and reports suggest that side effects and toxicity are very rare in dogs. But, that doesn’t mean there are no potential side effects. Some dogs may experience gastrointestinal upset when they take milk thistle. This can include diarrhea and vomiting, as well as general discomfort. If your dog experiences any of these side effects, you should contact your vet straight away.

Some dogs may also be allergic to milk thistle.

What To Do If Your Dog Experiences Side Effects

So, watch your dog closely when they first take milk thistle. And speak to your vet if you notice any strange behaviors or physical changes. If your vet isn’t open, you should take your dog to an emergency vet to be on the safe side. Especially if it is their first time taking milk thistle.

Stick to the dosage recommended by your vet. And do not mix with any other medications unless your vet has given them the OK. On top of this, it’s best to avoid giving milk thistle to pregnant dogs.

The Labrador Handbook by Pippa Mattinson

Milk Thistle for Dogs

Milk thistle is becoming a more common and more popular treatment for our pets. Especially those suffering from renal and liver issues. Hopefully, as this usage increases, we will see more studies investigating the efficacy and use of milk thistle for dogs.

Has your veterinarian recommended this treatment for your dog? Or has it improved the condition of your dog in the past? We would love to hear your stories in the comments.

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References and Resources

The Labrador Site Founder

Pippa Mattinson is the best selling author of The Happy Puppy Handbook, the Labrador Handbook, Choosing The Perfect Puppy, and Total Recall.

She is also the founder of the Gundog Trust and the Dogsnet Online Training Program 

Pippa's online training courses were launched in 2019 and you can find the latest course dates on the Dogsnet website


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