Milk Thistle or Silymarin

What is milk thistle?

milk_thistle1Milk thistle is an herbal remedy that has been used for around 2000 years in the treatment of various health concerns. The Latin name for milk thistle is Silybum marianum. The active ingredient of milk thistle is a flavinoid called silymarin that is found in the seeds. Most herbal preparations contain extracts that are derived from crushed seeds and are standardized to contain a specific concentration of silymarin.

"...silymarin has strong antioxidant and anti-inflammatory actions..."

Scientific studies of milk thistle suggest that silymarin has strong antioxidant and anti-inflammatory actions, that it has detoxifying actions, and that it promotes cellular repair and regeneration. Literature reviews of clinical studies using silymarin appear to show mixed results of its effectiveness; however, when the studies are reviewed critically it appears that the therapeutic effects of silymarin are dose related.

What conditions are treated with milk thistle?

milk_thistle2Milk thistle has a long history of use in the treatment of liver problems, particularly to treat chronic hepatitis, liver cirrhosis, toxin-induced liver damage and gall bladder disorders. In addition to its antioxidant and anti-inflammatory properties, it stimulates the flow of bile from the gall bladder, that has lead to some herbalists recommending it for treatment of some bowel disorders. Historically, it has been successfully used as an emergency antidote to mushroom poisoning - if given within 24 hours, it significantly reduces the risk of liver damage and death.

Other research suggests that milk thistle promotes kidney function in patients with kidney damage due to diabetes, that it may protect the kidneys from the toxic effects of certain drugs and from radiation injury, and that it may reduce insulin resistance in certain cases of adult onset diabetes.

Laboratory studies also suggest that milk thistle extracts may have anti-cancer effects. Specifically, studies have shown that it may slow the growth of certain cancer cells, that it may potentiate or enhance the activity of some chemotherapy drugs, and that it may protect the by preventing the cells from dividing, by shortening their life span and/or by reducing the blood supply to the cancer cells. Research is ongoing regarding the role of silymarin in cancer treatment, particularly whether it should be avoided in the treatment of liver cancer (since it promotes liver regeneration it could conceivably stimulate the growth of certain types of liver cancer).

Why recommend the use of milk thistle in my pet?

"Both traditional herbal uses and experimental research support the use of milk thistle in the treatment of liver disorders..."

Both traditional herbal uses and experimental research support the use of milk thistle in the treatment of liver disorders as outlined above. It may also be of benefit in the treatment of insulin-resistant diabetes mellitus, and in the treatment of inflammatory conditions of other internal organs. Finally, it may be recommended as part of the treatment protocol for certain cancers.

How much experience is there with the use of milk thistle in pets?

Veterinary herbalists and holistic practitioners have recommended the use of milk thistle in dogs and cats for many years. In recent years, its use in the treatment of liver disorders has become more commonplace with mainstream veterinary practitioners.

How safe is milk thistle?

Milk thistle appears to be a safe and well-tolerated herb for animals. Side effects are usually mild and usually involve the gastrointestinal tract, such as loose stools or mild digestive upsets. Since there is a potential concern with its use in liver cancer, it may be wise to avoid its use in these cases unless recommended by your veterinarian.

"Milk thistle is not recommended for use in humans during pregnancy..."

Milk thistle is not recommended for use in humans during pregnancy, and this same precaution should be observed in animals.

Where do I obtain milk thistle and do I need a prescription?

Milk thistle is available as an extract or tincture. Pet owners are cautioned against buying supplements without knowledge of the manufacturer, as supplements are not highly regulated and some supplements may not contain the labeled amount of ingredients. Your veterinarian may have preferred brands of supplements that he or she will recommend. A prescription is not needed for milk thistle.

Related Tags

thistle, silymarin, treatment, liver, herbal, cancer, supplements, antioxidant, diabetes, anti-inflammatory, herbalists, flavinoid, marianum, silybum

Looking to learn more?

We also offer free, instant access to over 1,500 related articles on your pet's health including preventive medicine, common and not so common diseases, and even informative case studies. We encourage you to read any of these popular articles below or search our extensive pet health library.

Most Popular Articles

About our approach to exceptional pet health care

At VCA Animal Hospitals, our veterinarians take you and your pet's health seriously. With over 600 hospitals and 1,800 fully qualified, dedicated and compassionate veterinarians, we strive to give your pet the very best in medical care. We understand your pet is an extension of you, and appreciate the opportunity to share in providing exceptional pet care and quality of life.

* Free initial health exam for new clients only. Not to be combined with any other offer. Not good toward boarding, grooming, prescription and non-prescription medication, and retail items. Not good toward emergency and/or specialty veterinary services. Coupon good for up to two pets (dogs or cats only) per household. Redeemable only at a general practice VCA Animal Hospital. For pet owners who are aged 18 and older.

If you are a new client, you can get a free first exam* on your first visit.

Free First Exam

Get to know us by visiting one of our neighborhood hospitals.

Locate a Hospital