Can Denamarin Cause Diarrhea In Dogs?

Denamarin is a wonder drug given to dogs for liver diseases and to accompany hepatotoxic drugs. But can Denamarin cause Diarrhea in dogs too? Let’s find out!

Denamarin is a commonly prescribed composition drug for pets that may cure liver diseases and protect hepatic cells. However, in larger than recommended doses, Denamarin may interfere with gastrointestinal activities, causing side effects such as Diarrhea. 

Let’s dive into facts to know more about the drug and find answers to your questions about Denamarin and canine hepatitis. 

Can Denamarin Cause Diarrhea In Dogs

What is Denamarin, and Why is it used?

Denamarin is a common drug that veterinary specialists prescribe to cure liver distress or protect a dog’s liver from liver-damaging medications. 

Chemical composition

The main active substances of Denamarin are adenosylmethionine, and a combination of Silybin A and B. S-adenosylmethionine or SAM-e is involved in various metabolic reactions such as group transfer reactions, transsulfuration, etc. 

Most of these reactions occur in the liver, and thus products of these reactions and SAM-e is primarily absorbed in the liver. A substance of similar chemical composition is naturally present in your dog’s body, and Denamarin is nothing but a manufactured form of this naturally occurring chemical substance. 


Denamarin increases liver function efficiency and protects it by increasing the number of antioxidant molecules in your dog’s body. Therefore, it protects hepatic cells and cures hepatocellular diseases such as liver failure. 

Sometimes, vets need to prescribe medications to dogs that can potentially damage liver cells. Many medicines, such as deworming medications, can negatively impact your dog’s liver. 

In such cases, doctors prescribe drugs like Denamarin along with those medications. Denamarin protects your dog’s liver from any attack that the medication might impose on a dog’s liver.

Can Denamarin Cause Diarrhea In Dogs

Liver Distress in Dogs


Liver disorders are pretty common across all breeds. There could be hundreds of reasons for liver distress in dogs. Some of the common causes of liver diseases are 

  • Ingestion of poisonous plant objects such as Amanita mushrooms
  • Accidental ingestion of liver-damaging drugs, insecticides, herbicides, and molds. Acute, chronic hepatitis can result from prolonged ingestion of drugs that can potentially harm the liver cells, such as chemotherapy medication. 
  • Microbial infections and toxoplasmosis can cause infectious hepatitis.
  • Problems related to hormones that are endocrine diseases can cause liver failure. Endocrine disorders such as diabetes, hyperthyroidism, and hypothyroidism can induce liver failure. 
  • Liver cysts can cause acute hepatitis in dogs.
  • Carcinoma of the liver can cause severe liver failure.
  • Many disorders are inherited from parents, and dogs suffer from that since birth. These types of diseases are called congenital disorders. Defects in metabolic pathways of Glycogen and Protein metabolism can cause severe problems in the liver. Hereditary conditions are one of the leading causes of chronic hepatitis.


Whatever be the cause, liver distress has common symptoms such as vomiting, excessive thirst, frequent urination, gastrointestinal problems, jaundice, and ulcers in the gastrointestinal tract. 

Diagnosis & Treatment

Veterinary specialists often diagnose liver distress with a liver function test. Liver function tests in dogs measure levels of liver enzymes to identify any problem in the liver. 

Can Denamarin Cause Diarrhea In Dogs

Treatment often includes drugs like Denamarin, increases the level of liver enzymes and protects the hepatic cells. In case of acute liver failure, vets treat the symptoms and the cause.

It would be best to schedule preliminary tests like LFT (liver function tests) and RFT (renal function tests) every six months for your dogs. 

Denamarin Mechanism Of Action

Denamarin enhances the concentration of antioxidants such as Glutathione in dogs.

As mentioned earlier, the active substances of Denamarin are S-adenosylmethionine and Sibyl in. Both work together to provide adequate support to the liver.

S-adenosylmethionine increases the concentration of antioxidants, especially Glutathione. Low levels of Glutathione are expected in dogs which decreases hepatocellular activity and negatively affects liver and gallbladder functions. 

Glutathione prevents hepatic cell toxicity and prevents necrosis or death of liver cells. 

Sibylin, on the other hand, shows different mechanisms of action to reduce oxidative stress in the liver. 

Some studies found that Sibylin increases protein synthesis in liver cells and increases Glutathione levels in the liver. It is also known to show phagocytic action in the liver. 

Can Denamarin Cause Diarrhea In Dogs

Overall, Sibylin helps in the regeneration of liver cells. The joint action of Siblyn and S-adenosylmethionine protects liver cells against various ailments and drugs imposing harm to the liver. 

For example, Denamarin is prescribed to dogs who receive chemotherapy as drugs involved in chemotherapy are engaged in the depression of liver cells. Denamarin could also be used effectively in mushroom poisoning. 

Another alternative to Denamarin is Milk Thistle, but it is not known to provide adequate support as Denamarin does. It has S-adenosylmethionine but lacks the incorporation of Sibyl in. 

Sibyl- infused Denamarin options are also available in the market, which fails to cure liver diseases but is used for other health benefits and your dog’s overall well-being. You should consult a veterinary specialist before administering these drugs to your dog. 

Appropriate Dosage of Denamarin 

Small breed dogs 1-2 tabs a day, Mid-size/Large dogs: 2-4 pills a day.

Denamarin is used as both a preventive medication and treatment drug. Denamarin is used for dogs who are on other medications that are known to have liver-damaging effects. In this case, Denamarin is used to prevent liver damage from the potent hepatotoxic drug. Hepatotoxic drugs are medications that damage liver cells in the liver. 

Denamarin is also found to show a reverse effect, and that is, it might damage the liver cells if administered in higher concentrations. Therefore, it would be best to consult your vet to know the appropriate dosage of Denamarin given to your dog. 

Can Denamarin Cause Diarrhea In Dogs

According to the bottle’s label, you should give Denamarin to your dog two times a day, but the dosage needs to be reduced gradually. Denamarin needs to be given to your dog when it has an empty stomach. Your dog must not eat one to two hours before or after giving Denamarin to your dog. 

Denamarin is marketed in two forms, chewable tablets, and syrup. The number of tablets or volume of syrup a dog needs is variable. Like any veterinary medicine, Denamarin’s dosage depends on the dog’s size, weight, and condition. 

Your small breed dog might need one to two tablets a day, while your large dog might need 2-4 pills a day. The chewable tablets are advised to be given as a whole and not grind before giving them to your dog. 

Side-effects of Denamarin 

Denamarin suits a large variety of dogs. It contains a herb called rag-weed. If your dog is allergic to ragweed, it will not be able to tolerate Denamarin. Besides such allergy, other side-effects of Denamarin are infrequent, but few of the following side-effects are observed in some dogs. 

One of the significant drawbacks of a seemingly perfect drug, Denamarin, is that it can cause gastrointestinal problems in dogs. This means an upset stomach and irritated intestine, and these gastrointestinal problems give rise to the following side-effects of Denamarin.

Lack of Appetite

Your dog might refuse to intake any food or water. You might not observe it at first, but your dog would either refuse to eat his food or not only eat a bite-size amount of food. Your dog might even reject his favorite food. 

These are clear indications of inappetence in dogs. You can try replacing Denamarin or provide an additional appetite stimulator drug along with Denamarin. It is essential to mention that Denamarin can increase appetite, but sometimes the opposite is seen in dogs.

Can Denamarin Cause Diarrhea In Dogs

Vomiting Tendency

After consuming Denamarin, your dog might feel uneasy and nauseous, resulting in vomiting. Your dog might throw up the entire undigested meal or a yellow mass of acidic liquid. Both are indications of severe indigestion and could be a potential side-effect of Denamarin.


Although rare, Denamarin can cause Diarrhea in dogs. You would observe the liquid consistency of your dog’s poop. Your dog might suffer from more frequent bowel movements, and other problems such as nausea, vomiting, and abdominal pain will accompany.  

Frequently Asked Questions 

What are the side effects of Denamarin?

Vomiting, Diarrhea, and lack of appetite. Allergic reactions to ragweed.

Denamarin is well tolerated in most dogs, but it could trigger a few side effects such as diarrhea, vomiting, and inappetence. 
If your dog is allergic to ragweed, Denamarin is likely to cause allergic reactions in your dog. 
It is advised to look for any abnormality such as lack of appetite in your dog and report back to your vet about the observed effect of Denamarin.

How long should my dog take Denamarin?

It depends on how long the underlying condition lasts. Consult with your vet.

The duration of Denamarin administration could depend on the condition your dog is suffering from or the purpose for which Denamarin is prescribed. For example, suppose your dog takes Denamarin to prevent liver damage from other drugs. 

In that case, it needs to continue taking Denamarin as long as the other liver-damaging medication is continued. It is advised to reduce the dosage gradually.

Does Denamarin upset dogs’ stomachs?

Yes, it may. Denamrin may cause gastrointestinal problems, including indigestion, diarrhea, and an upset stomach.

Can high liver enzymes cause Diarrhea in dogs?

Yes, high liver enzymes can cause Diarrhea as over-exposure to enzymes to Glutathione could reverse its primary protective effect.

Can liver supplements cause Diarrhea in dogs?

Yes, liver supplements include chemicals such as SAM-e that increase the production of Glutathione which can cause gastrointestinal problems, including Diarrhea.

Yes! Denamarin Can Cause Diarrhea 

Denamarin can cause Diarrhea along with other gastrointestinal disorders such as vomiting, nausea, irregular bowel movements, etc. Denamarin shows mild to negligible side effects in dogs and is widely used to protect liver cells in dogs. 

Thank you for reading, we hope we answered all your queries about Denamarin, its uses, side effects, and allergies. You might also want to read about other drugs such as Zzzquil and Benadryl and how they affect your dog.