Denamarin for Dogs: Uses, Dosage, and Side Effects

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The liver is a remarkable organ capable of healing and regenerating. Even dogs with liver disease can have a positive prognosis, and there are many things we can provide our dogs to support liver health, including diet and supplements, such as Denamarin.

Denamarin is available in tablet and chewable form.
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What is Denamarin for dogs?

Denamarin is a liver supplement for dogs that is made by Nutramax Laboratories. Nutramax Denamarin contains silybin and S-Adenosylmethionine, more commonly known as SAMe. Denamarin is available only by prescription by a veterinarian. It comes in chewable tablets and enteric-coated tablets, and it's packaged for small dogs, medium dogs, and large dogs. Denamarin is safe for dogs and is effective in supporting healthy liver function. Contact your veterinarian immediately if you see any changes in behavior or appearance.


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Denamarin for medium dogs is generally for dogs 13 to 34 pounds. Denamarin for large dogs is generally for dogs above 35 pounds. Denamarin for cats and small dogs are for either animal up to 12 pounds. Always follow the usage instructions on your particular package, but in general, chewable Denamarin tablets should be given on an empty stomach at least one hour before a meal for optimal absorption.


Denamarin for dogs: Primary uses?

The active ingredients in Denamarin support liver and brain health.‌ The supplement helps brain health by maintaining SAMe levels in the fluid surrounding the brain. Silybin is the active ingredient in milk thistle extract. It helps the body maintain a healthy oxidative balance, which supports and protects both the brain and the liver.


Can Denamarin treat liver disease in dogs?

Denamarin can be useful in treating liver disease‌, especially in combination with a diet designed to support healthy liver function.

SAMe, one of the ingredients in Denamarin, has multiple benefits for a dog's liver:


  • Helps prevent the death of liver cells
  • Encourages liver cell regeneration and repair
  • Raises liver levels of glutathione, which is an antioxidant

Your pet's liver function will be periodically monitored by your veterinarian. Some dogs with chronic liver disease will be on Denamarin long term to keep their liver enzymes in check, while other dogs may only need it for the short term.


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Denamarin for dogs dosage

Your veterinarian will prescribe Denamarin based on your dog's size, and they'll provide usage instructions. Most small, medium, and large dogs will take one tablet per day, but very large dogs may be prescribed two or three of the large-dog tablets daily. The number of tablets administered may gradually be reduced or increased at any time at the recommendation of your veterinarian.



Here are some tips for administering Denamarin for optimal absorption:

  • If possible, your dog should not eat overnight before taking the tablet.
  • If that's not possible, allow at least two hours after feeding your dog to administer the tablet.
  • Use a pill pocket if your dog is reluctant to eat the tablet.
  • Allow at least one hour before feeding your dog.
  • Store it in a cool, dry place.


Denamarin side effects in dogs

The ingredients in Denamarin are safe for dogs. Potential but very rare side effects of silybin include headaches, gastrointestinal problems, and itching. However, in clinical trials, these symptoms were observed only in primates. Even when given dosages of silybin extraordinarily higher than the amount in Denamarin, dogs have shown no ill effects. Mild digestive upset may occur in dogs taking milk thistle, the herb containing silybin.


Side effects of SAMe are rare and limited to mild gastrointestinal irritation and nausea. SAMe, which can heighten moods, may not be suitable for highly excitable dogs.

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Denamarin or milk thistle for dogs?

Both Denamarin and milk thistle are supplements that support healthy liver function.‌ The only difference between Denamarin and milk thistle is that in addition to silybin, Denamarin also contains SAMe. Milk thistle can be easier to find in a variety of forms and at a lower cost, while Denamarin is prescribed by a veterinarian and comes with dosing instructions.


Milk thistle has specifically been shown to help reduce the side effects of cancer treatments, but it should be used with caution. Very high doses of milk thistle may increase the toxicity of chemotherapy. While the silybin helps stimulate liver regeneration, researchers also have concerns that it may stimulate growth of liver tumors, although research is not conclusive.

Additional supplements

Veterinarians may recommend that dogs who need additional liver support take the supplement Marin along with Denamarin. Marin provides an additional dose of silybin as well as vitamin E and zinc. The formula is designed to increase the bio-availability of silybin compared to that of milk thistle supplements. Nutramax also makes Denoysl and Denamarin Advanced.

The bottom line

Denamarin is considered a highly safe and effective pet health liver health supplement. It may be used temporarily or long term for dogs with liver disease. Side effects are rare and mild. Consult your veterinarian for dosing advice.