Denosyl contains SAMe (S-Adenosylmethionine) to help support liver and brain health.

How does Denosyl® work?

Denosyl has been shown to markedly increase liver levels of glutathione,1,2 an important compound for liver health formed when SAMe (S-Adenosylmethionine) is metabolized. Denosyl has also been shown to help protect liver cells from cell death3,4 and may help cell repair and regeneration.5

While best known for supporting the liver in dogs and cats, research has shown that the SAMe in Denosyl may help support cognitive function in dogs.6 Denosyl provides SAMe in a stabilized form to help with brain health and act as a neuroprotector.7-9

Administration of Denosyl Tablets

Because the tablet must be kept intact to prevent destruction by moisture, administration range is based on the nearest whole-tablet. The chart below is provided as a guide for administration. Daily administration may also be calculated based on 20 mg/kg of body weight and rounded to the closest tablet size or combination of sizes.

For optimal absorption, tablets should be given on an empty stomach, at least one hour before feeding, as the presence of food decreases the absorption of S-Adenosylmethionine. Studies have shown that, in many cases, tablets or capsules given as a “dry swallow” do not pass into the stomach in cats but may become lodged in the esophagus. It is recommended for pet owners to administer 3-6 cc of water immediately following any tablet administration to speed passage of the tablet into the stomach.10,11 Denosyl 90 mg tablets are ideal for cats because of their small size. If the pet is to receive more than one tablet daily, the total number of tablets may be divided between morning and evening for ease of administration. For example, a daily administration of three tablets could be divided into two tablets in the morning and one tablet in the evening.

Denosyl Canine and Feline Daily* Administration Guide

For Cats (90 mg)
Body Weight Body Weight Number of Tablets Per Day
Up to 12 lbs Up to 5.5 kg 1 tablet
Over 12 lbs Over 5.5 kg 2 tablets
For Small Dogs (90 mg)
Body Weight Body Weight Number of Tablets Per Day
Up to 12 lbs Up to 5.5 kg 1 tablet
For Medium Dogs (225 mg)
Body Weight Body Weight Number of Tablets Per Day
13-34 lbs 6-15.5 kg 1 tablet
For Large Dogs (425 mg)
Body Weight Body Weight Number of Tablets Per Day
35-65 lbs 16-29.5 kg 1 tablet
66-120 lbs 30-54.5 kg 2 tablets
Over 120 lbs Over 54.5 kg 3 tablets

*The number of tablets can be gradually reduced or increased at any time depending on the pet's needs.
Many pets are maintained long-term on every-other-day or every-third-day administration.


Store in a cool dry place. Keep tablets in original blister pack until used. Tablets are sensitive to moisture and extreme heat.

Frequently Asked Questions

What formulations of Denosyl are available?

Denosyl is available enteric-coated tablets for cats and dogs.

How much Denosyl should I give my pet?

Your veterinarian will advise you as to the amount to initially administer. Depending on your pet’s response and status, your veterinarian may eventually adjust this amount to meet your pet’s individual needs. Remember, Denosyl enteric-coated tablets should not be broken. When increasing or decreasing their administration, adjustments should be done in full tablet increments. Some pets are given Denosyl only for a short period of time, although Denosyl may be used longer in other animals.

What should I look for when I give Denosyl?

While response varies, owners may note a change in their pet’s appetite, activity, and attitude.

How will my veterinarian monitor my pet's response while on Denosyl?

Your veterinarian will likely recommend follow-up examinations, blood work, and/or other laboratory work to check on how well your pet is doing with Denosyl and how it may be helping to support your pet’s liver function.

Are there any side effects?

Denosyl has been shown to be well-tolerated by both dogs and cats with a wide margin of safety.

Can Denosyl be used with other products?

Yes, your veterinarian may recommend combining Denosyl with other products and/or dietary modifications. One such product is called Marin® Plus, which can be administered with Denosyl for additional liver health support. There are no known adverse interactions of Denosyl with drugs or other supplements. Denosyl may even protect against negative effects on the liver caused by some medications.

Are other brands the equivalent to Denosyl?

While other S-Adenosylmethionine (SAMe) products are available, there can be a significant variance in product quality and activity levels of SAMe. Denosyl is produced using high-quality, researched ingredients and under strict manufacturing standards.

Since S-Adenosylmethionine is made from methionine, should I give my pet methionine?

Administration of methionine is not recommended. Providing high levels of methionine to pets with liver compromise may not increase the production of natural S-Adenosylmethionine and has been shown in some cases to increase liver damage.

Liver Product Selector

What Product is Right for My Pet?
Nutramax Laboratories Veterinary Sciences, Inc. Liver Health Supplements DenamarinDenamarinDenamarin Product Marin PlusMarin Plus Marin Plus Product DenosylDenosylDenosyl Product
Species For Dogs
For Cats
Supplement Form
Supplement Form Enteric-coated Tablet
Chewable Tablet
Soft Chew
Active Ingredients
Active Ingredients
SAMeIncreases levels of glutathione which is an important compound protecting liver health.
Silybin The silybin found in Denamarin and Marin Plus for dogs is complexed with phosphatidylcholine which has been shown to increase absorption 4x in dogs compared to standardized milk thistle extracts.
Vitamin E An antioxidant that has been shown to help protect liver function.
Zinc Supplementation may be beneficial in dogs with long-term decreased liver function as these dogs often have low liver zinc levels. Zinc participates in many enzymatic reactions within the body, and any deficiency may have harmful effects. Zinc is not in Marin for Cats as deficiencies have not been noted in cats.
Curcumin Curcumin has been shown to inhibit several mediators, supporting a healthy inflammatory response. It also helps increase production of glutathione, the liver's main antioxidant and “detoxifier” and protects against fibrotic changes in the liver.
Medium Chain Triglyceride (MCT) Oil In the liver, MCTs can be used for energy for metabolic reactions. MCTs can also help reduce fat deposition, which may occur in the liver secondary to compromise.
Suggested Uses When administration on an empty stomach is needed
Administration with food is needed
When zinc and/or Vitamin E may benefit
When a more economical choice is preferred
For brain health
Nutramax Laboratories Veterinary Sciences, Inc. Liver Health Supplements DenamarinDenamarinDenamarin Product Marin PlusMarin Plus Marin Plus Product DenosylDenosylDenosyl Product


  1. Center SA, Warner K, Hoffman WE, et al. Am J Vet Res 2005;66:330-341.
  2. Center SA, Randolph JF, Warner K, et al. J Vet Intern Med 2005;19:303-314.
  3. Webster CRL, Boria P, Usechak P, et al. Vet Therapeutics 2002;3:474-484.
  4. McCool J, Johnston A, Webster CRL. In Proceedings. 21st Annual ACVIM Forum 2003;abstract #134.
  5. Center SA. In Proceedings. 18th Annual ACVIM Forum 2000;550-552.
  6. Rème CA, Dramard V, Kern L, et al. Vet Therap 2008;9(2):69-82.
  7. Tchantchou F, Graves M, Ortiz D, et al. J Nutr Health Aging 2006;10(6):541–544.
  8. Tchantchou F, Graves M, Falcone D, Shea TB. J Alzheimers Dis 2008;14:323–328.
  9. Shea TB, Chan A. J Alzheimers Dis 2008;13:67–70.
  10. Westfall DS, Twedt DC, Steyn PF, et al. J Vet Intern Med 2001;15(5):467-470.
  11. Graham JP, Lipman AH, Newell SM, Roberts GD. Am J Vet Res 2000;61(6):655-657.

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