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90 mg 30 ct Cats & Small Dogs Up To 12l bs.
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Product Info
How to Use
Customer Reviews
Product Info
What is Denosyl?

Denosyl is a daily supplement that helps support proper liver function. Support of a compromised liver, regardless of the cause, is essential if function is to be improved. Denosyl has not only been shown to markedly increase glutathione levels in the livers of dogs and cats, but to go far beyond that. Denosyl has been shown to protect liver cells from cell death and may be useful in cell repair and healing. Its main ingredient is S-Adenosylmethionine (SAMe).


Cats and Dogs

  • Increases glutathione levels, an important antioxidant that protects your pet's cells from dangerous toxins
  • Improves a pet's liver health
  • No reported side effects
How it Works:

Denosyl has been shown to increase the level of glutathione, an antioxidant that can fight deadly toxins in your pet's body. For optimal absorption, it should be taken on an empty stomach.


Denosyl tablets must be given to your pet whole. Store this product in a cool and dry place. Keep tablets in the original blister pack until they are used.

Brand Name:

Denosyl (Nutramax)

Active Ingredient(s):


What is this product used for:

Denosyl has been shown to increase hepatic glutathione levels in cats and dogs. Glutathione is a potent antioxidant that protects liver cells from toxins and death. Denosyl is recommended to improve hepatic glutathione levels in compromised animals to help maintain and protect liver function.


Denosyl is a non-prescription (OTC) product available as 90mg, 225mg and 425mg stabilized tablets.

How this product should be used:

The tablets should be given on an empty stomach at least one hour before feeding. Research shows that, if possible, a fasting period of 8-12 hours before giving this product is optimal. The usual dose in cats and dogs is based on weight. For pets up to 12 lbs give 1 tablet of the 90mg strength, for pets 13 to 34 lbs give 1 tablet of the 225mg strength, for pets 35 to 65 lbs give 1 tablet of the 425mg strength, for pets 66 to 120 lbs give 2 tablets of the 425mg strength and for pets over 120 lbs give 3 tablets of the 425mg strength. When giving more than 1 tablet the total number of tablets may be divided into morning and evening. For example, a dose of 3 tablets could be divided into 2 tablets in the morning and 1 tablet in the evening.

What are the side effects:

There are no reported side effects. However, Denosyl should be used with caution when given with medications such as amitriptyline, fluoxetine, clomipramine, tramadol, or Mitaban Dip.

What special precautions are there:

Tablets must be given whole. Do not break or split. Research shows that this product may be of benefit to pets that are also taking primidone, Phenobarbital, prednisone, azathioprine, cyclosporine and certain anti-depressants.

In the event of overdose:

Contact a veterinarian or veterinary emergency room.

How should I store this product:

Store this product in a cool, dry, place. Keep tablets in the original blister pack until used. Tablets are sensitive to moisture and extreme heat and should not be split or crumbled. Keep out of the reach of children.

How to Use
  • Denosyl is a Liver Support Formula.
  • Denosyl is available for small dogs and cats, medium dogs, and large dogs.
  • Do not crush or break the tablet as this will damage the tablet's enteric coat and inhibit absorption.
  • Do not remove tablets from blister pack until ready to use.

Denosyl should be given on an empty stomach at least one hour before feeding. If giving more than 1 tablet divide the daily dose between morning and evening.

Small Dogs and Cats - Denosyl (90 mg)
Up to 12 lbs
Give 1 tablet daily
Medium Dogs - Denosyl (225 mg)
13-34 lbs
Give 1 tablet daily
Large Dogs - Denosyl (425 mg)
35-65 lbs
Give 1 tablet daily
66-120 lbs
Give 2 tablets daily
121 lbs and over
Give 3 tablets daily
Do not use!

Should be stored in a cool dry place. Do not refrigerate.

Denosyl for Cats and Small Dogs:
Active Ingredients (up to 12 lbs)
90 mg
Denosyl for Medium Dogs:
Active Ingredients (13-34 lbs)
225 mg
Denosyl for Larger Dogs:
Active Ingredients (35 lbs and over)
425 mg
Customer Reviews
Denosyl is rated 4.5 out of 5 by 16.
Rated 5 out of 5 by from Genetic Liver Dysfunction My adopted beagle had seizure the second day after we brought her home. She was one year old then. We thought it was due to the new environment. Clinic vet prescribe her with only some relaxant medication and vitamins. She continues to have seizure once every few weeks. Till a serious episode in the middle of the night one day made us to bring her to the animal hospital. A thorough check by the vet and after few follow-up check diagnosed her with genetic liver dysfunction and also genetic epilepsy. Her liver reading was far exceeding the normal range. Denosyl had helped to keep her liver at normal range with her seizure medication that is not good for her liver . She is put on long term Denosyl, a pill a day before her l/d diet. She is healthy and active after 2 years now. All of us are happy with this cutie pie at home!
Date published: 2013-06-01
Rated 5 out of 5 by from Best Medicine in the World My 13yr old cat had blood work drawn for her dental and her ALT enzyme was 1965, normal level should be from 10-100. The vet recommended Denosyl and Prednosone for 30 days and to retest her levels. I got the results back today and her ALT is 44-which is astonishing. I was given the prognosis of having to put her down if the pill didn't work, and now we're instructed to give it to her 2x a week for maint. This pill is a miracle!! Lifesaver
Date published: 2012-09-11
Rated 5 out of 5 by from Miracle worker Maddie is my 12 year old bichon. She is my heart. I'm not sure about the technical terminology but one of her liver enzymes has been escalating for years and was way way above normal. It's supposed to be under 100 and her count was over 800. Shortly after giving her this pill that number was cut in half and it continues to go down, I am thrilled. Since the pill has to be given whole, it's kind of hard to give it to her. She hates it... But it is so worth it. I need my girl with me a long time, so she's taking it. It's very effective.
Date published: 2011-10-20
Rated 3 out of 5 by from Denosyl liver med's We use to be able to get this medicine in a small round orange pill. Was able to push down our dogs throat easily. Now they have changed this to a larger thicker oval shaped pill. Our little dog has trouble swallowing it. It says on the bottle not to be split or crumbled. It is too easy for a little dog to choke on it. It is also very difficult when says has to be on a empty stomach a hour before meals. We end up giving in the evening after meals. Getting this medicine from the Vet costs $32.50, the only good thing is PetMeds is only $17.99. But our Vet can at least get the small thin ones where Petmeds only has the long thick ones.
Date published: 2010-01-18
Rated 4 out of 5 by from life saver This drug literally saved my dog's life and has enabled her to continue to live 2 years past being diagnosed with liver failure. She was very sick and it took about 7 days on the denosyl before she improved. Don't give up if you are struggling with watching your dog suffer. It just might be the miracle you are praying for.
Date published: 2009-10-07
Rated 5 out of 5 by from My Kitties Liver enzymes are back to normal!! My old girl, Lilly, gets this every day... it works so well for her and I am so happy her liver is better. she is happy too!!
Date published: 2009-08-29
Rated 5 out of 5 by from Truely Amazing! When I got my 2lb MiKi he was playful but never too much. I called him my anorexic dog because it was a chore to get him to eat and even while training him I had to use toys instead of food. Well, when he went in to get neutered his liver enzyme count was over 1200 when it should be more in between 100-200. We went to the U of M where I found out after a biopsy that he had a liver infection that caused some major damage and they weren't sure how long he would last. My vet put him on Denosyl right away. The change was phenomenal in just a couple days. He ate with out a syringe...not a lot but he was only 1.5 lbs. He is now 3.5 pounds, almost 7 years old and he runs and plays like he is a puppy still. Still to this day when he is not on Denosyl I notice a metallic odor to his breath, he doesn't eat as much and he sleeps a lot more. When he is on it no bad breath, he is energetic and eats a lot, wakes me up early AND his liver count has dramatically dropped down to normal. Thanks to this product I truly believe he is going to get to live out the full length his life was intended to. PS I have to wrap it in something like cheese, peanut butter, or liverwurst for him to take it...AND sometimes I just have to push it down his throat...but well worth it.
Date published: 2009-08-08
Rated 5 out of 5 by from Great Product! My 14 yr. old miniature schnauzer has had liver disease for years and has been on Denosyl with great results. Just one difference than the product says, we have had to cut it in half and crush it for years and it still works great! She now has to eat 4 small meals a day and 1/2 crushed goes in 2 of those meals and she still continues to get the benefits and thrive though she still has liver disease of course.
Date published: 2009-02-11
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Is Denamarin 90 mg for sm dig, same as Denosyl? Generic?

Asked by: Maddie
The active ingredients in the Denamarin are S-Adenosylmethionine and Silybin A+B. The Denosyl's active ingredient only contains S-Adenosylmethionine .
Answered by: Cherley Petmeds Pro
Date published: 2016-11-13

Can my dog take denosyl and denamarin

Asked by: Anonymous
Hi there, These are both liver supplements so you would only use one of these products not both at the same time, unless directed by your veterinarian
Answered by: James PetMeds Pro
Date published: 2016-09-25

Can this pill be put in a pill pocket?

I have a hard time getting my dog to swallow the medicine. Am I able to put it in a pill pocket? Or is there some other way to get her to take it? She will spit it out even if I drop it down her throat. Thanks!
Asked by: Anonymous
Answered by: Lilli Pharmacist
Date published: 2015-06-19

My dog is diabetic, is this safe to give with insulin?

Asked by: Anonymous
Please consult with your vet prior to using this supplement due to your furry pal's medical condition.
Answered by: Anonymous
Date published: 2015-03-19

does S-adenosyl-225 have milk thistle in it

Asked by: Anonymous
Thank you for your question. Yes, S-Adenosylmethionine is milk thistle.
Answered by: Anonymous
Date published: 2014-09-06

Timing with food (cat)

I read the answer where it says: "The ideal situation is 8 - 12 hours after the last meal if possible." This isn't feasible for a cat; especially one that needs to keep eating at this point. It's also not feasible for my other household cats (withholding food). For this medication to work, what is the MINIMUM amount of time I must wait after a meal prior to giving the pill? Are there any formulations that do NOT require a waiting period (before or after food)? Thank you!
Asked by: Anonymous
For best results it should be given 1 hour before feeding on an empty stomach.
Answered by: Anonymous
Date published: 2014-06-11

denosyl - milk thistle

denosyl - milk thistle I have been giving my cat denosyl that I got from my vet and also liquid milk thistle. Are they both the same? The milk thistle is liquid and much easier to administer - should I discontinue one of them?
Asked by: Anonymous
Denosyl contains S-Adenosylmethionine (SAMe) known for protecting liver cells from cell death and may be useful in cell repair and healing. Milk thistle contains silybin which is known for protecting and promoting the growth of liver cells, fighting oxidation (a chemical process that can damage cells), and inhibiting inflammation. Please consult with your veterinarian with any concerns.
Answered by: Lilli Pharmacist
Date published: 2013-10-22

Can Denosyl be given w/CO Q10 & Salmon Oil?

Asked by: Anonymous
Yes there should be nothing wrong with adding this to your furry pals diet but since everyone can be affected different we would suggest to contact your vets office to make sure they agree that this is the best route for your furry pal.
Answered by: Anonymous
Date published: 2013-10-22
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