Best Cat Liver Support Supplements (2026) – Top 10 Reviewed
Your cat’s liver is their largest internal organ, responsible for detoxification, nutrient metabolism, bile production, and so much more. When liver health declines — whether from age, medication use, or illness — the effects can ripple through every system in your cat’s body. The right liver supplement can help support healthy function, promote detoxification, and aid in recovery. Here are the best liver support supplements to keep your feline’s most important organ working at its best.
Our Top Picks at a Glance
- Best Overall: Nutramax Denamarin for Cats – Gold standard vet-recommended liver support with SAMe and silybin
- Best Value: Vet Classics Liver Support Tablets – Affordable comprehensive formula for cats and dogs
- Best Premium: Pet Wellbeing Milk Thistle for Cats – Organic, vet-formulated single-herb liquid
Quick Comparison
| Product | Key Ingredients | Form | Servings | Best For |
|---|---|---|---|---|
| Nutramax Denamarin for Cats | S-Adenosylmethionine (SAMe), Silybin | Tablets | 30 | Overall liver health and protection |
| Vet Classics Liver Support Tablets | B Vitamins, Glutathione, Milk Thistle, Dandelion Root | Chewable Tablets | 60 | Budget-friendly comprehensive support |
| Pet Wellbeing Milk Thistle for Cats | Organic Milk Thistle (Silymarin) | Liquid | 60+ | Organic herbal liver detox |
| ProHepatic Liver Support for Cats | Silybin-Phosphatidylcholine (Siliphos), Zinc | Tablets | 30 | Advanced antioxidant liver protection |
| Rx Vitamins Hepato Support | Milk Thistle, B Complex Vitamins | Capsules | 180 | Long-term liver maintenance |
| HomeoPet Liver Rescue | Homeopathic Herbal Blend | Liquid Drops | 90+ | Natural homeopathic liver cleanse |
| Standard Process Feline Hepatic Support | Whole-Food Based Ingredients | Tablets | 90 | Whole-food liver nutrition |
| SilymarinAdvanced Liver Health for Cats | Milk Thistle, SAMe, Silybin | Tablets | 30 | Advanced silybin-SAMe combination |
1. Nutramax Denamarin for Cats – Best Overall
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Denamarin is the supplement that veterinarians reach for first when a cat needs liver support — and for good reason.
The formula combines S-Adenosylmethionine (SAMe) with silybin, the most bioactive component of milk thistle. SAMe supports the production of glutathione, the liver’s most important antioxidant, while silybin promotes liver cell regeneration and provides additional antioxidant protection. This dual-action approach makes Denamarin effective for both liver protection and recovery.
Nutramax Laboratories has been producing veterinary supplements for decades and uses evidence-based formulations. Denamarin is recommended by more veterinarians than any other liver supplement and has a long track record of helping cats with elevated liver enzymes, hepatic lipidosis, and other liver conditions.
What We Like
- Gold standard vet-recommended liver supplement with SAMe and silybin
- Supports both liver protection and regeneration simultaneously
- Decades of veterinary trust and clinical evidence
What Could Be Better
- Best given on an empty stomach, which can be tricky with cats
- 30-day supply per bottle means frequent repurchasing
Bottom Line: Denamarin is the undisputed leader in feline liver support, combining the two most effective liver-supporting ingredients in one veterinarian-trusted formula.
2. Vet Classics Liver Support Tablets – Best Value
- HIGH-QUALITY PET HEALTH SUPPLEMENT: Help support normal liver function for cats and dogs with this pet health supplement that includes a blend of vitamins, probiotics, antioxidants and herbs to help manage toxins and strengthen pet immunity.
- PET SUPPLEMENTS FOR LIVER SUPPORT: Crafted for dogs and cats, Vet Classics’ Liver Support soft chews and chewable tablets feature a blend of B-vitamins, glutathione, milk thistle and dandelion root to support healthy liver functions.
- SUPPORT IMMUNITY IN DOGS, CATS: The formulation of this pet health supplement supports healthy liver functions for dogs, horses and cats, especially senior animals, by managing toxins to strengthen pet immunity.
- VETERINARIAN FORMULATED AND RECOMMENDED: Each soft chew and chewable tablet of this liver support supplement is infused with herbal ingredients and a complex blend of enzymes to support healthy liver function and help support overall wellness for dogs and cats.
- PREMIUM PET SUPPLEMENTS: Since 1994, VetClassics has offered a high-quality line of pet health supplements developed by veterinarians and scientists to support care for dogs, cats and horses. Choose from an impressive collection of pet health supplements that address hip and joint support, cardiovascular care, liver and urinary support.
With B vitamins, glutathione, milk thistle, and dandelion root packed into affordable chewable tablets, Vet Classics delivers comprehensive liver support without the premium price.
This formula supports healthy liver function by boosting cell growth, bile production, and toxin management. The blend of herbal ingredients and enzymes has been formulated by veterinarians and scientists to address liver health from multiple angles — detoxification, antioxidant protection, and immune support.
Vet Classics has over 30 years of supplement manufacturing experience and operates from an FDA-registered, cGMP-compliant facility. The 60-count bottle provides a solid two-month supply at a price point that’s significantly lower than most competitors.
What We Like
- Comprehensive formula with B vitamins, glutathione, milk thistle, and dandelion
- 60 chewable tablets at a very affordable price
- 30+ years of veterinary supplement manufacturing expertise
What Could Be Better
- Designed for dogs and cats — dosing requires adjustment for felines
- Chewable format may not appeal to all cats
Bottom Line: Vet Classics offers the best bang for your buck in liver support, providing a veterinarian-formulated multi-ingredient formula at a fraction of premium prices.
3. Pet Wellbeing Milk Thistle for Cats – Best Premium
- 🌿 PURE ORGANIC MILK THISTLE – Single-herb supplement featuring certified organic milk thistle extract, traditionally used to support normal liver function and overall vitality in cats. Provides gentle, holistic care with no unnecessary additives.
- 🐾 LIVER WELLNESS SUPPORT – Rich in natural antioxidants that help maintain the normal production and renewal of liver cells. Supports healthy metabolic processes, helping your cat’s body function at their best every day.
- 💧 EASY LIQUID ADMINISTRATION – Alcohol-free liquid formula allows for optimal absorption and precise administration. Natural bacon flavor is well-accepted by most cats, making daily wellness care simple for pet parents.
- 🏆 VET-FORMULATED EXCELLENCE – Crafted by holistic veterinarians and clinical herbalists. Made in the USA in FDA-registered facilities and certified by the NASC for quality assurance. Every batch is third-party tested for purity and efficacy.
- 🌼 HOLISTIC WELLNESS TRADITION – Milk thistle has been valued for centuries for its supportive role in normal detoxification and overall well-being. A thoughtful addition to your cat’s daily wellness routine, helping them feel vibrant and cared for.
For cat owners who want a pure, organic, single-herb liver supplement, Pet Wellbeing’s milk thistle liquid is the gold standard in herbal liver care.
This supplement features certified organic milk thistle extract, delivering silymarin — the active compound known for its powerful liver-protective properties. Silymarin acts as a potent antioxidant, stimulates liver cell regeneration, promotes detoxification, and supports healthy metabolic processes.
The alcohol-free liquid formula comes in a natural bacon flavor that many cats enjoy, making daily administration relatively painless. Made in FDA-registered facilities with NASC certification, this is one of the highest-quality milk thistle products available for cats.
What We Like
- Certified organic milk thistle for maximum purity
- Alcohol-free liquid with natural bacon flavor cats enjoy
- NASC-certified, vet-formulated in FDA-registered facilities
What Could Be Better
- Single-herb formula — doesn’t include SAMe or other liver-supporting ingredients
- Premium price for a 2 oz bottle
Bottom Line: If you want the purest, highest-quality milk thistle supplement for your cat’s liver, Pet Wellbeing delivers organic herbal excellence in an easy-to-administer liquid.
4. ProHepatic Liver Support for Cats – Best Antioxidant Formula
- ProHepatic is a liver support formula for dogs and cats with no SAMe
- ProHepatic is a potent antioxidant formulation that provides liver function support and protection from various causes of liver disease, including oxidation
- The main ingredient is Siliphos , which is a complex of silybin, the main active constituent of milk thistle, and phosphatidylcholine.
- Especially beneficial for pets taking NSAIDs
ProHepatic uses Siliphos — an exclusive silybin-phosphatidylcholine complex — for enhanced absorption and superior antioxidant liver protection.
The main ingredient, Siliphos, combines silybin (the most active component of milk thistle) with phosphatidylcholine, dramatically improving absorption compared to standard milk thistle extracts. Added zinc and bioflavanols provide additional antioxidant support.
Customer reviews consistently report that ProHepatic effectively normalizes liver enzyme levels. Multiple cat owners have noted their cats’ ALT levels returning to normal ranges after starting this supplement. The tiny tablet size is particularly suitable for small cats.
What We Like
- Siliphos complex provides superior absorption of silybin
- Tiny tablet size is easier for cats to swallow
- Proven track record of normalizing liver enzyme levels
What Could Be Better
- Only 30 tablets per bottle
- Pricier than standard milk thistle supplements
Bottom Line: ProHepatic’s advanced silybin-phosphatidylcholine complex makes it the most bioavailable milk thistle option, delivering better absorption and more effective liver protection.
5. Rx Vitamins Hepato Support – Best for Long-Term Use
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With 180 capsules per bottle, Rx Vitamins provides the longest-lasting liver support supplement designed for consistent daily use over months and years.
This formula combines milk thistle extract with a B vitamin complex for comprehensive hepatic support. The B vitamins support liver metabolism and energy production, while milk thistle provides antioxidant protection and promotes liver cell health.
Rx Vitamins is a trusted veterinary supplement brand, and Hepato Support is frequently recommended by vets for cats needing ongoing liver maintenance. The capsule contents can be opened and sprinkled on food for easier administration.
What We Like
- 180 capsules per bottle — excellent for long-term supplementation
- Milk thistle plus B vitamins for liver metabolism support
- Capsules can be opened and sprinkled on food
What Could Be Better
- Capsule format may be challenging for some cats
- Designed for dogs and cats, requiring feline dose calculation
Bottom Line: Rx Vitamins Hepato Support is the best choice for cats needing consistent, long-term liver supplementation, offering outstanding value with 180 capsules per bottle.
6. HomeoPet Liver Rescue – Best Natural Homeopathic Option
- CAT & DOG SUPPLEMENT: HomeoPet Liver Rescue may help cleanse your pet’s liver while supporting healthy liver, kidney, and digestive system functions.
- SAFE & NATURAL LIVER SUPPLEMENT: This cat and dog kidney-health support is formulated with safe, gentle, and natural homeopathic ingredients and has no known side effects.
- DOG & CAT LIVER DETOX FOR ALL AGES: This natural formula is well tolerated by and approved for all ages of dogs, cats, and other small pets like birds and rabbits.
- EASY DOSING: Dose medicine directly into mouth, in water, or at meal/snack time 2 times a day for 21 days. Repeat every 3 months for optimal results.
- SIMPLE, SAFE & PURE: Daniel H. Farrington and his veterinarian brother, Thomas Farrington, created HomeoPet to bring high-quality, safe, natural, and affordable treatments and supplements to pets and pet parents worldwide.
HomeoPet’s gentle homeopathic approach to liver cleansing makes it ideal for cats who need support without the intensity of pharmaceutical-grade supplements.
This natural liquid formula may help cleanse the liver while supporting healthy liver, kidney, and digestive system functions. The safe, gentle homeopathic ingredients have no known side effects, making this supplement appropriate for cats and kittens of all ages.
The recommended protocol is dosing twice daily for 21 days, then repeating every three months for optimal results. The liquid drops can be given directly, mixed with water, or added to food.
What We Like
- Gentle homeopathic formula with no known side effects
- Supports liver, kidney, and digestive system simultaneously
- Safe for all ages including kittens
What Could Be Better
- Homeopathic approach may not provide enough support for severe liver conditions
- Requires a 21-day dosing protocol repeated quarterly
Bottom Line: HomeoPet Liver Rescue is the gentlest liver supplement available, perfect for preventative care or mild liver support without any risk of side effects.
7. Standard Process Feline Hepatic Support – Best Whole-Food Formula
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Standard Process delivers liver support through whole-food based ingredients that provide natural, bioavailable nutrition for hepatic health.
This feline-specific formula supports hepatic circulation, liver metabolism, and immune function using Standard Process’s signature whole-food approach. Many of the ingredients are grown on their own organic farm in Wisconsin, ensuring premium quality from soil to supplement.
Holistic veterinarians frequently recommend Standard Process products because the whole-food ingredients are more easily recognized and utilized by the body compared to synthetic alternatives. The 90-tablet bottle provides a generous supply for daily use.
What We Like
- Whole-food based ingredients for natural bioavailability
- Specifically formulated for cats (not a dog formula adapted for felines)
- Trusted by holistic veterinarians for decades
What Could Be Better
- Tablet format requires creative administration for picky cats
- Higher price reflects premium whole-food sourcing
Bottom Line: Standard Process is the top choice for cat owners who prefer a whole-food, minimally processed approach to liver support with ingredients the body naturally recognizes.
8. SilymarinAdvanced Liver Health for Cats – Best Advanced Formula
- ADVANCED LIVER HEALTH SUPPORT – With your beloved fluff's health in mind, our milk thistle supplement for cats provides powerful liver support with 90mg of SAMe and 9mg of Silybin from Milk Thistle, aiding in liver detox and repair. Keep your cat liver health at its best
- NATURAL LIVER DETOX – Packed with anti-inflammatory flavonoids, our liver supplements for cats help eliminate toxins and harmful chemicals from your pet's liver, promoting healthy liver function and overall well-being. Protect your cat from harmful toxins and ensure a cleaner, healthier liver.
- COGNITIVE FUNCTION BOOST – Our supplement with SAMe for cats, not only supports liver health but also enhances cognitive brain functions, helping to improve mental clarity and vitality in your cat. Keep your cat sharp, alert, and mentally vibrant at any age.
- PURE & SAFE FORMULA – No chemical coatings, artificial colors, or flavors. Our Milk Thistle Cat supplement is gluten-free, non-GMO, and free of magnesium stearate and titanium dioxide, ensuring a safe, natural product for your pet. Provide your cat with pure, all-natural ingredients.
- VETERINARIAN DESIGNED – Developed with veterinary and nutritional experts, this formula is easy to administer with one uncoated tablet a day, providing convenient, affordable liver health care for your cat. Our cat liver supplement is trusted by experts to ensure your cat’s well-being and recovery.
SilymarinAdvanced combines milk thistle, SAMe, and silybin in one advanced formula for cats that need maximum liver support.
This newer entry to the feline liver supplement market brings together the three most researched liver-supporting ingredients in veterinary medicine. Milk thistle provides broad antioxidant protection, SAMe supports glutathione production, and silybin promotes liver cell regeneration. Having all three in one tablet simplifies supplementation compared to using multiple products.
The formula is specifically sized for cats and veterinarian-recommended. For cat owners who have been using separate SAMe and milk thistle products, this combined formula offers both convenience and potentially better synergistic effects.
What We Like
- Combines milk thistle, SAMe, and silybin in one formula
- Eliminates the need for multiple separate liver supplements
- Cat-sized tablets for easier administration
What Could Be Better
- Newer product with less long-term track record than Denamarin
- 30 tablets per bottle means monthly repurchasing
Bottom Line: SilymarinAdvanced is the best all-in-one liver supplement for cats needing comprehensive hepatic support, combining the three most effective ingredients in a single daily tablet.
How to Choose the Best Cat Liver Support Supplement
The most important factor in choosing a liver supplement is the active ingredients. SAMe (S-Adenosylmethionine) supports the production of glutathione, the liver’s master antioxidant. Silybin and silymarin from milk thistle protect liver cells from damage and promote regeneration. The best supplements contain at least one of these key ingredients, and premium formulas contain both.
Consider your cat’s specific liver situation. Cats with diagnosed liver disease may need pharmaceutical-grade supplements like Denamarin or ProHepatic, while cats on long-term medications may benefit from daily milk thistle for preventative liver protection. Senior cats often benefit from gentle herbal or whole-food liver support as part of their wellness routine.
Pay attention to the supplement format. Many liver supplements work best when given on an empty stomach, which can be challenging with cats. Liquid supplements and powders that can be mixed into a small amount of food offer more flexibility than tablets that need to be given whole.
Quality certifications are particularly important for liver supplements. Look for products manufactured in GMP-certified, FDA-registered facilities with NASC quality seals. The liver is responsible for processing everything your cat ingests, so you want to be certain the supplement itself is pure and free from contaminants.
Benefits of Cat Liver Support Supplements
Liver supplements provide antioxidant protection that shields liver cells from damage caused by toxins, medications, and metabolic waste. This protection is especially important for cats on long-term medications, as many drugs are metabolized by the liver and can cause hepatic stress over time.
Supplements containing SAMe and silybin actively promote liver cell regeneration. The liver is one of the few organs capable of regenerating itself, and these ingredients support this natural repair process, helping damaged liver tissue recover more effectively.
Liver support supplements also improve the organ’s detoxification capacity. A healthy liver efficiently filters toxins, produces bile for fat digestion, and metabolizes nutrients. When supplemented properly, your cat’s liver can perform these essential functions more effectively, leading to better overall health, energy, and vitality.
Frequently Asked Questions
What are the signs of liver problems in cats?
Common signs include loss of appetite, increased thirst and urination, vomiting, weight loss, lethargy, and yellowing of the skin, gums, or eyes (jaundice). If you notice any of these symptoms, consult your veterinarian immediately for proper diagnosis and treatment.
Can liver supplements replace veterinary treatment?
No. Liver supplements should complement, not replace, proper veterinary care. If your cat has been diagnosed with liver disease, work with your veterinarian to create a comprehensive treatment plan that may include diet changes, medications, and appropriate supplements.
How long does it take for liver supplements to work?
Most cat owners see improvements in energy and appetite within two to four weeks. Liver enzyme levels typically take four to eight weeks of consistent supplementation to show measurable improvement on blood tests. Some cats with severe liver issues may need longer to respond.
Should I give liver supplements to my healthy cat?
Preventative liver supplementation can be beneficial for senior cats, cats on long-term medications, or cats exposed to environmental toxins. Milk thistle is generally considered safe for long-term preventative use. Consult your veterinarian about whether your healthy cat would benefit from liver support.
Can I give my cat human milk thistle supplements?
It’s not recommended. Human milk thistle supplements may contain dosages and additional ingredients that are unsuitable for cats. Always use a product specifically formulated for cats or approved for multi-species use with appropriate feline dosing.
What does SAMe do for a cat’s liver?
SAMe (S-Adenosylmethionine) supports the production of glutathione, the liver’s primary antioxidant. Glutathione plays a critical role in liver detoxification, cell protection, and immune function. Supplementing with SAMe helps maintain optimal glutathione levels, especially in cats with compromised liver function.
Are there foods that support liver health in cats?
A balanced, high-quality diet supports overall liver health. Some veterinarians recommend foods that are easy to digest with moderate protein levels and adequate essential fatty acids. For cats with liver disease, your vet may prescribe a specific hepatic diet formulated to reduce the liver’s workload.
Can I give my cat multiple liver supplements at once?
In some cases, yes — for example, combining a SAMe-based supplement with a phosphate binder or probiotic. However, always discuss your supplement plan with your veterinarian to avoid ingredient duplication or potential interactions.
