Milk Thistle for Dogs: Dosage, Benefits, Precautions & More

Milk Thistle for Dogs - Dosage, Benefits, Side Effects

Is milk thistle safe for dogs? How does it help?

Milk thistle is a flowering plant with red to purple flowers and pale green leaves that are networked with white veins.

It was originally native to southern Europe and Asia. However, it is nowa found in almost every country in the world. The plant produces flowers depending on seasons. That is; it flowers from June through August in the northern hemisphere while in the southern hemisphere, the flowering seasons are December through to February.

Can dogs eat milk thistle?

Yes! Dogs can eat milk thistle since it has little to no side effects when consumed by dogs. It is used therapeutically as a supplement to cleanse the body of of both people and dogs alike from toxins, and is a natural therapeutic agent supporting healthy liver function.

Milk thistle supplements are available in three formulations:

  • Powder
  • Capsules
  • Liquid form

The most commonly used formulation for dog products is a chewable capsule, and it is considered a dietary supplement.

The therapeutically active ingredient is silymarin, and is extracted form the plant for supplement formulation.

The prepared medication from milk thistle is approved for use in humans for treatment of certain disease conditions. It is also prepared in dosages appropriate for dogs, and cats.

What are the benefits?

Milk thistle has a lot of health benefits for dogs. It is among the least toxic medications with limited side effects.

This property makes milk thistle a preferable treatment option for some conditions. Here are the conditions that can be managed by milk thistles for dogs:

Managing dog seizures

Since antiquity, most communities have used herbs to manage seizures. However, some herbal medicines have been shown to induce seizure.

Seizures resulting as a side effect of drugs are very hard to manage by contemporary medicine.  They also take time to resolve. In some cases, the seizures don’t resolve at all.

Some studies have shown that milk thistle can be used as a natural remedy for seizures. Although studies in this subject have not been adequately documented, it may help prevent seizures in your dog.

However, you should not self-prescribe medications for your dog especially for those conditions that involve the central nervous system.

Conditions such as seizures are very delicate and need only to be handled by a professional. You inadequacy of veterinary knowledge may compromise the health of your dog and lead to severe and adverse effects that may lead to the death of your dog.

Do not use milk thistle for dogs to manage seizures unless it is prescribed by your veterinarian.

1. Milk thistle helps in detoxification

Milk thistle powerfully cleanses the liver. It also helps in regeneration of liver cells following an injury.

For instance, milk thistle can help reverse the harmful effects of alcohol when consumed. It can also eliminate the adverse effects of pesticides ingested through contaminated food.

Milk thistle also cleanses the body off of heavy metals acquired through drinking water, polluted air when breathed in and poisons of any kind.

The major detoxification center in the body is the liver. All blood passes through the liver so that the body can be cleansed from toxic substances.

For the systems in the body to work in harmony and efficiently, the liver needs to be in a constant state of health for effective blood cleansing process.

The role of milk thistle in cleansing the liver and encouraging its regeneration after damage potentially enhances the ability of the liver to remove toxins from the body.

2. Preventing cancer

Milk thistle contains a flavonoid called silymarin.  This compound is a potent antioxidant which helps combat oxidative stress in the body.

It decreases the risk of cancer development in dogs by acting as a natural booster of the immune system.

With its antioxidant properties, it prevents DNA damage by radicals. This property also helps in reversing cancer growth and progression.

According to a research posted in the National Center for Biotechnology information (NCBI) Journal of Cancer, it was found out that silymarin can prevent the proliferation of three colon cancer cell lines.

Milk thistle also contains an antioxidant called silibinin. This compound stimulates the synthesis of proteins and activates the transduction of signals that alters the membrane of healthy cell.

This action protects the cells from damage and also inhibits the occurrences of mutations that might cause cancer inside the cell.

3. Preventing diabetes

Evidence that silymarin, when taken simultaneously with conventional treatment, can help in controlling the symptoms of diabetes have been cited by the National Institute of health.

The antioxidants found in milk thistle have been experimentally studied and reported as being able to reduce blood sugar levels in patients resistant to insulin.

Therefore, feeding your dog on milk thistle can actually help in managing blood sugar levels due to diabetes.

What diseases does milk thistle treat in dogs?

The liver is the major organ targeted by milk thistle therapy. This is because milk thistle has great potential in supporting the liver and detoxifying the body.

For a long time now, milk thistle has proved relevant in the management of the following diseases of the liver:

a) Toxin induced liver disease

The liver is charged with the duty of cleansing the body against toxins. However, the level of intoxication may be so high that the liver becomes overwhelmed.

When this happens, you suffer from a condition called toxin induced liver disease. It leads to liver insufficiency and abdominal discomfort.

Silymarin, the major component of milk thistle, can cleanse the liver by facilitating rapid elimination of these toxins.

It then enhances the regeneration of the damaged tissues of the liver thereby restoring the liver to its normal working conditions.

The major cause of toxin-induced liver disease in dogs is feeding your dog or letting him or her consume certain species of toxic mushrooms.

b) Acute and chronic viral hepatitis

Viral hepatitis is an infection of the liver by viruses. The common viruses causing this disease are somewhat unrelated.

They include: Hepatitis A, Hepatitis B, Hepatitis C, Hepatitis D and Hepatitis E. Apart from the hepatitis viruses, cytomegalovirus and Epstein Bar virus can also cause inflammation of the liver.

This inflammation can be chronic or acute.

Milk thistle helps in relieving oxidative stress by eliminating the free radicals that encourage the progression of inflammatory processes.

In this regard, it prevents the inflammation from spreading and affecting other structures of the liver.

If the damage caused is irreversible, milk thistle will encourage a compensatory proliferation of cells to replace the damaged cells – a process called compensatory hepatic hyperplasia.

c) Cushing’s disease

This disease is also known as Cushing’s syndrome. It occurs due to increased levels of cortisol in the blood.

In the body, cortisol production is stimulated by the hormone, adrenocorticotropic hormone (ACTH).

ACTH levels increase when there is a disorder with the pituitary gland – where it is produced. Ectopic sites may also produce ACTH, such as certain cancers.

This eventually increases the level of cortisol leading to Cushing’s syndrome. In most cases, surgery may be used to correct the symptoms.

However, certain scientific studies have proven that silibinin, a component of milk thistle, can be used as an alternative treatment for Cushing’s disease.

Some research on animal models also posits that milk thistle can be used to manage lung tumors, which in most cases are the ectopic sites for ACTH production.

Other conditions that are believed to be susceptible to milk thistle include multiple myeloma and lymphoblastic leukemia.

Besides the aforementioned diseases, milk thistle can also be used to manage conditions such as:

  • Tumors of the liver since it can slow down the growth and spread of tumors.
  • Skin problems that have arisen secondary to diseases of the liver.
  • The coat of your dog may start thinning out in certain areas.
  • Fatty liver – a condition where visceral fat is transported and deposited in the liver often due to excess intake of calorie-rich foods.
  • Canine leptospirosis – a bacterial infection.
  • Pancreatitis in dogs.

Milk thistle dosage for dogs

The dosages of milk thistle recommended for dogs should contain about 80% silymarin. Conveniently, most of the supplements used in dog food range between 100 and 200 milligrams of the herb.

For dogs suffering from liver disease that has advanced, milk thistle dosages of 200 mg per 5kg body weight can be administered. This is approximately 200 mg per 10 pounds body weight.

When used to manage other health conditions, a dosage of 50 to 100 mg per 5kg body weight is sufficient to produce desirable results.

However, certain dosages may precipitate serious side effects to your dog such as stomach upset; build up of stomach gas and mild diarrhea.

When this happens, reduce the dosages and monitor your dog for changes in these side effects.

If the effects persist, discontinue the therapy and report to your veterinarian so that he or she can assess the health condition of your dog.

What is the best product/supplement to buy?

Are you confident about introducing your dog to mill thistle? Maybe you are not aware that your dog has liver problems. You may also not be aware of the various milk thistle products available for sale.

Conveniently, there are numerous products made from milk thistle that are available for pet owners. The most products that are characteristically favored by most pet owners have been explained below.

They include:

1. Lignans for Life Milk Thistle for Dogs

Lignans for life milk thistle supplements are available as capsules.

This formulation is convenient when used in dog food.

It has powerful abilities for balancing hormones in the body. It regulates the hormone cortisol.

In this regard, several researchers posit that it is an effective treatment alternative for Cushing’s disease in dogs.

It also helps in managing diseases of the liver and gallbladder. Its anti-inflammatory effects are also important in managing various inflammatory processes in the body.


  • Lignans for life Milk thistle for dogs is very efficient at cleansing the liver, managing Cushing’s disease and treating inflammatory conditions.
  • It is also relatively less expensive hence affordable by most pet owners.


  • Most of the online selling sites for Lignans for life Milk thistle capsules for dogs do not include appropriate dosages in the packaging.
  • It, therefore, presents a risk of toxicity when administered blindly without a prescription.
  • You should, therefore, consult your veterinarian instead of buying and administering the medication by yourself.
  • The risks are more pronounced when the supplement is used to manage Cushing’s disease.

2. Pet Wellbeing Milk Thistle for Dogs

Pet wellbeing milk thistle is a formula prepared from organically grown or selectively imported herbs.

It is an excellent product for the management of toxicity in the body. It also has admirable liver support abilities due to its effectiveness in alleviating symptoms of toxicities caused by medication.

The Food and Drug Administration Center for Veterinary Medicine Guidelines has certified the use of pet wellbeing milk thistle in veterinary practice.

Pet wellbeing milk thistle, therefore, complies with the provisions outlined for any good dietary supplement for dogs.

This product is made in liquid formulations that have no other active ingredient other than milk thistle itself.


  • The greatest feature of pet well-being milk thistle is that it is glycerin based and hence safer for dogs. Other products of its caliber are mostly alcohol based and may be toxic to dogs.
  • It also has no alteration in the taste of your dog’s food when supplemented with the diet.


  • Since pet wellbeing milk thistle is very beneficial and appropriate for its use, it is among the priciest products of its kind.

Precautions and safety information

Contraindication in healthy dogs

It is beyond any reasonable doubt that milk thistle is among the best herbs for supporting the liver.

However, you should be aware of the following:

Contraindication in pregnancy

Scientists suggest use of silymarin in pregnant people is contraindicated due to its possible effects on the health of the developing fetus.

Hence, it is wise to assume that milk thistle can also be teratogenic in dogs.

These findings may be insufficiently studied in veterinary medicine, but for the sake of your lovely pooch, your best companion – you should take extra caution when she is pregnant.

Allergic reactions

Milk thistle may also precipitate serious allergic reactions in dogs that are sensitive to the family of plants called Asteraceae. These plants include; ragweed, marigolds and daisies.

If your dog is allergic to this family of plants or if your dog is prone to allergic reactions, you may consider talking to your veterinarian before using milk thistle to supplement your dog’s food.

Dogs with diabetes

Milk thistle can potentially lower the blood sugar levels in dogs with diabetes. This might alter the therapeutic regiment for the treatment of diabetes in your dog.

Therefore, you should consult with your veterinarian before administering milk thistle to your dog. This will help in preventing the alteration of dosages by the chemicals in milk thistle.

Dogs with estrogen-sensitive tumors

Milk thistle has the tendency of metabolically yielding estrogen-like substances that mimic the action of estrogen in the body.

Certain tumor conditions are made worse by excess estrogen. Therefore, if your dog is suffering from tumors that are sensitive to estrogen, your doctor will discourage you from using milk thistle to your dog.

These conditions are quite serious and should be put into consideration to prevent the deterioration of your dog’s health

You should not use milk thistle for prophylaxis. A prophylactic substance is a medication given before a disease condition occurs to those who are susceptible to the disease.

Using milk thistle as a prophylactic agent for preventing liver disease in your dog may damage the healthy liver of your lovely pet.

Possible side effects

In most cases, milk this is relatively safe when taken orally – through the mouth. However, some dogs may experience mild side effects after consuming milk thistle.

It these dogs, it can trigger gastrointestinal problems such as:

  • Diarrhea
  • Nausea
  • The coat of your cat may start thinning out in certain areas.
  • Increased intestinal gas
  • Bloating or fullness accompanied by pain
  • Loss of appetite.

Side effects on the skin

Milk thistle may also lead to the development of skin conditions due to its ability to cause an allergic reaction. These conditions include:

  • Urticaria
  • Eczema
  • Rash
  • Pruritus

Neurotic disorders

Moreover, milk thistle may cause neuro disorders such as:

  • Headache
  • Malaise
  • Insomnia

It may also lead to impotence. Additional side effects of milk thistle may include arthralgia, rhinoconjunctivitis and anaphylaxis.

These symptoms are not experienced by your dog all at once. Only a few of them may be present in your dog.

Better still; some dogs may not experience any of these side effects. If the side effects are producing adverse symptoms, you should not hesitate to contact your veterinarian so that you can figure out how to help your dog.


Using milk thistle for dogs is certainly among natures best therapeutic agents for managing canine diseases. However, that does not guarantee that it is 100% safe.

Despite the health benefits, milk thistle should not be prophylactically used in healthy dogs since large doses can suppress liver functions in healthy dogs.

Some dogs may show hypersensitive reactions or pronounced adverse side effects. You should, therefore, monitor your dog closely during the period of administering milk thistle supplements.

Managing side effects may involve reducing the dosages or completely stopping the treatment regimen.

However, the best option is always to seek professional attention for your dog to ensure that your lovely pooch gets only the best of treatment.

This will also guarantee a good prognosis for the condition affecting your dog of the treatment plan is correctly adhered to as indicated by the veterinarian.