Cat’s claw side effects


Cat’s claw

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Table of Contents > Herbs > Cat’s claw

Overview Plant Description What is It Made Of? Available Forms How to Take It Precautions Possible Interactions Supporting Research

Named after its hook-like horns, cat’s claw (Uncaria tomentosa) is a woody vine native to the Amazon rainforest and other places in South and Central America. The bark and root have been used by South Americans for centuries to treat health problems including arthritis, stomach ulcers, inflammation, dysentery, and fevers. It was also used as a form of birth control.

Test tube studies indicate that cat’s claw may stimulate the immune system, help relax the smooth muscles (such as the intestines), dilate blood vessels (helping lower blood pressure), and act as a diuretic (helping the body eliminate excess water).

Cat’s claw also has antioxidant properties, helping the body eliminate particles known as free radicals that damage cells. Scientists believe free radicals to contribute to health problems, including heart disease and cancer. Antioxidants can help neutralize free radicals and may reduce, or even help prevent, some of the damage they cause.

Some early studies suggest cat’s claw may kill tumor and cancer cells in test tubes.


Not many scientific studies have looked at the safety and effectiveness of cat’s claw, but it has been used traditionally to treat osteoarthritis (OA). One study found that it may help relieve pain from knee OA without significant side effects.

Rheumatoid arthritis

Cat’s claw has been suggested as a treatment for rheumatoid arthritis (RA) because it may help reduce inflammation. One small study of people who were already taking sulfasalazine or hydroxychloroquine to treat RA found that those who also took cat’s claw had fewer painful, swollen joints than those who took a placebo (dummy pill). But although cat’s claw may help reduce inflammation, there is no evidence to show that it stops joint damage from getting worse. For that reason, RA should be treated with conventional medications, which can stop joint damage.

Further research

Cat’s claw is being studied for a number of other possible uses, including HIV, Crohn disease, multiple sclerosis, systemic lupus erythematosus (SLE or lupus), endometriosis, kidney problems, bladder cancer, and Alzheimer disease. More research is needed before scientists can say whether it is effective.

Plant Description

Cat’s claw is a thorny vine that can climb as high as 100 feet. It grows mostly in the Amazon rainforest, as well as tropical areas in South and Central America. Much of the cat’s claw sold in the United States was grown in Peru.

Cat’s claw got its name from the curved, claw-like thorns that grow on its stem. The root and bark of cat’s claw are the parts used for medicine.

What is It Made Of?

Cat’s claw contains many types of plant chemicals that help reduce inflammation, such as tannins and sterols, and fight viruses, such as quinovic acid glycosides.

Cat’s claw preparations are made from the root and bark of the cat’s claw vine. How effective the root and bark are may depend on what time of year the plant was harvested.

Available Forms

The bark of the cat’s claw vine can be crushed and used to make tea. Standardized root and bark extracts (containing 3% alkaloids and 15% phenols) are also available in either liquid or capsule forms.

How to Take It


No one has studied cat’s claw in children, so no one knows whether it is safe. DO NOT give a child cat’s claw except under your doctor’s supervision.


Speak to your health care provider regarding dosing instructions.


The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects, and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.

Cat’s claw appears to have few side effects, however, there have not been enough scientific studies on cat’s claw to determine its safety. Some people have reported dizziness, nausea, and diarrhea when taking cat’s claw. The diarrhea or loose stools tend to be mild and go away with continued use of the herb.

Pregnant or nursing women should not take cat’s claw because it may cause miscarriage.

People with autoimmune diseases, skin grafts, tuberculosis, or those receiving organ transplants should not use cat’s claw unless specifically directed by their physician because of its possible effects on the immune system.

People with leukemia or low blood pressure should not take cat’s claw.

People with kidney or liver disease should not use cat’s claw without first asking their doctor.

Possible Interactions

If you are currently taking any of the following medications, you should not use cat’s claw without first talking to your health care provider.

Medications that suppress the immune system: In theory, because cat’s claw may stimulate the immune system, it should not be used with medications that suppress the immune system. Those include cyclosporine or other medications prescribed following an organ transplant, or to treat an autoimmune disease.

Blood-thinning medications: Cat’s claw may increase the risk of bleeding, especially if you also take blood thinners such as aspirin, warfarin (Coumadin), or clopidogrel (Plavix).

Diuretics (water pills): Cat’s claw may act as a diuretic, helping the body eliminate excess fluid. If you also take diuretics, which do the same thing, you could be at risk of developing an electrolyte imbalance.

Blood pressure medication: Cat’s claw may lower blood pressure. If you take medication for high blood pressure, taking cat’s claw may cause your blood pressure to be too low.

Other medications: Cat’s claw may interfere with some medications that are processed by the liver. If you take any medications, check with your doctor before taking cat’s claw.

Supporting Research

de Fatima Fernandes Vattimo M, da Silva NO. Uncaria tomentosa and acute ischemic kidney injury in rats. Rev Esc Enferm USP. 2011;45(1):194-8.

Gonzales GF, Valerio LG. Medicinal plants from Peru: a review of plants as potential agents against cancer. Anticancer Agents Med Chem. 2006;6(5):429-44.

Kaiser S, Dietrich F, de Resende PE, et al. Cat’s claw oxindole alkaloid isomerization induced by cell incubation and cytotoxic activity against T24 and RT4 human bladder cancer cell lines. Planta Med. 2013;79(15):1413-20.

Keplinger K, Laus G, Wurm M, et al. Uncaria tomentosa (Willd.) Dethnomedicinal use and new pharmacological, toxicological and botanical results. J Ethnopharmacol. 1999;64:23-34.

Miller MJ, Mehta K, Kunte S, Raut V, Gala J, et al. Early relief of osteoarthritis symptoms with a natural mineral supplement and a herbomineral combination: a randomized controlled trial . J Inflamm (Lond). 2005 Oct 21;2:11.

Mur E, Hartig F, Eibl G, et al. Randomized double blind trial of an extract from the pentacyclic alkaloid-chemotype of uncaria tomentosa for the treatment of rheumatoid arthritis. J Rheumatol. 2002 Apr;29(4):678-81.

Nogueira N, Coelho TM, Aguiar GC, et al. Experimental endometriosis reduction in rats treated with Uncaria tomentosa (cat’s claw) extract. Eur J Obstet Gynecol Reprod Biol. 2011;154(2):205-8.

Piscoya J, Rodriguez Z, Bustamante SA, et al. Efficacy and safety of freeze-dried cat’s claw in osteoarthritis of the knee: mechanisms of action of the species Uncaria guianensis. Inflamm Res. 2001;50(9):442-448.

Rosenbaum CC, O’Mathúna DP, Chavez M, Shields K. Antioxidants and antiinflammatory dietary supplements for osteoarthritis and rheumatoid arthritis. Altern Ther Health Med. 2010 Mar-Apr;16(2):32-40. Review.

Setty AR, Sigal LH. Herbal medications commonly used in the practice of rheumatology: mechanisms of action, efficacy, and side effects. Semin Arthritis Rheum. 2005 Jun;34(6):773-84. Review.

Sheng Y, et al. Induction of apoptosis and inhibition of proliferation in human tumor cells treated with extracts of Uncaria tomentosa. Anticancer Res. 1998;18:3,363-3,368.

Sheng Y, Pero RW, Wagner H. Treatment of chemotherapy-induced leukopenia in a rat model with aqueous extract from Uncaria tomentosa. Phytomedicine. 2000;7(2):137-143.

Spelman K, Burns J, Nichols D, et al. Modulation of cytokine expression by traditional medicines: a review of herbal immunomodulators. Altern Med Rev. 2006 Jun;11(2):128-50. Review.

Steinberg PN. Cat’s claw: medicinal properties of this Amazon vine. Nutrition Science News. 1995.

Review Date: 6/22/2015
Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Generic Name: cat’s claw (CATS CLAW)
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Medically reviewed by on Sep 30, 2019 – Written by Cerner Multum

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What is cat’s claw?

Cat’s claw is a plant that is also known as Griffe Du Chat, Liane du Pérou, Life-Giving Vine of Peru, Samento, Uña De Gato.

Cat’s claw has been used in alternative medicine as a possibly effective aid in treating arthritis. People with either osteoarthritis or rheumatoid arthritis have used cat’s claw. Different forms of cat’s claw may be specific to treating each type of arthritis. Follow your healthcare provider’s instructions about which form to use.

Other uses not proven with research have included stomach and intestinal disorders, hemorrhoids, chronic fatigue syndrome, herpes, shingles, chickenpox, hay fever, and many other conditions.

It is not certain whether cat’s claw is effective in treating any medical condition. Medicinal use of cat’s claw has not been approved by the FDA. Cat’s claw should not be used in place of medication prescribed for you by your doctor.

Cat’s claw is often sold as an herbal supplement. There are no regulated manufacturing standards in place for many herbal compounds and some marketed supplements have been found to be contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Cat’s claw may also be used for purposes not listed in this product guide.

Important Information

Follow all directions on the product label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

Ask a doctor, pharmacist, or other healthcare provider if it is safe for you to use this product if you have:

  • an autoimmune disorder such as multiple sclerosis, lupus, or psoriasis;

  • leukemia; or

  • low blood pressure.

Do not use cat’s claw if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

It is not known whether cat’s claw passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this product.

Do not give any herbal/health supplement to a child without medical advice.

How should I take cat’s claw?

When considering the use of herbal supplements, seek the advice of your doctor. You may also consider consulting a practitioner who is trained in the use of herbal/health supplements.

If you choose to use cat’s claw, use it as directed on the package or as directed by your doctor, pharmacist, or other healthcare provider. Do not use more of this product than is recommended on the label.

Do not use different forms (tablets, liquid, tincture, teas, etc) of cat’s claw at the same time without medical advice. Using different formulations together increases the risk of an overdose.

If you need surgery, stop taking cat’s claw at least 2 weeks ahead of time.

Call your doctor if the condition you are treating with cat’s claw does not improve, or if it gets worse while using this product.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra cat’s claw to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking cat’s claw?

Avoid taking other herbal/health supplements such as casein protein, coenzyme Q-10 (ubiquinone), fish oil, L-arginine, lycium, or stinging nettle. Combining cat’s claw with any of these substances may cause your blood pressure to get too low.

Cat’s claw side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Although not all side effects are known, cat’s claw is thought to be possibly safe when taken for a short period of time.

Common side effects may include:

  • dizziness;

  • headaches; or

  • vomiting.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect cat’s claw?

Do not take cat’s claw without medical advice if you are using a medication to treat any of the following conditions:

  • any type of infection (including HIV, malaria, or tuberculosis);

  • anxiety or depression;

  • asthma or allergies;

  • cancer;

  • erectile dysfunction;

  • heartburn or GERD;

  • high blood pressure, high cholesterol, or a heart condition;

  • migraine headaches;

  • psoriasis, rheumatoid arthritis, or other autoimmune disorders;

  • a psychiatric disorder; or

  • seizures.

Tell your doctor about all other medicines you use, and those you start or stop using during your treatment with cat’s claw, especially:

  • birth control pills or hormone replacement therapy; or

  • drugs that weaken the immune system such as cancer medicine, steroids, and medicines to prevent organ transplant rejection.

This list is not complete. Other drugs may interact with cat’s claw, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

  • Consult with a licensed healthcare professional before using any herbal/health supplement. Whether you are treated by a medical doctor or a practitioner trained in the use of natural medicines/supplements, make sure all your healthcare providers know about all of your medical conditions and treatments.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2018 Cerner Multum, Inc. Version: 1.05.

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Professional resources

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Related treatment guides

  • Herbal Supplementation


There are many ways to treat high blood pressure, including lifestyle changes and/or medications. If you are interested in turning to traditional and herbal treatments for lowering your blood pressure, you have many options.

If you are thinking of trying herbs for medical reasons, whether that means using the whole herb or a supplement, speak to your doctor first. Some herbs, especially in large quantities, may produce undesirable side effects or interfere with other medications.

Basil is a delicious herb that goes well in a variety of foods. It also might help lower your blood pressure. Extract of basil has been shown to lower blood pressure, although only briefly. Adding fresh basil to your diet is easy and certainly can’t hurt. Keep a small pot of the herb in your kitchen garden and add the fresh leaves to pastas, soups, salads, and casseroles.


Cinnamon is another tasty seasoning that requires little effort to include in your daily diet, and that may bring your blood pressure numbers down. Consuming cinnamon every day has been shown to lower blood pressure in people with diabetes.

Include more cinnamon in your diet by sprinkling it on your breakfast cereal, oatmeal, and even in your coffee. At dinner, cinnamon enhances the flavor of stir fries, curries, and stews.


Cardamom is a seasoning that comes from India and is often used in the foods of South Asia. A study investigating the health effects of cardamom found that participants given powdered cardamom daily for several months saw significant reductions in their blood pressure readings.

You can include cardamom seeds or the powder in spice rubs, in soups and stews, and even in baked goods for a special flavor and a positive health benefit.


This pungent seasoning can do more than just flavor your food and ruin your breath. Garlic has the ability to lower your blood pressure by causing your blood vessels to relax and dilate. This lets blood flow more freely and reduces blood pressure.

You can add fresh garlic to a number of your favorite recipes. If the flavor of garlic is just too strong for you, roast it first. And if you simply can’t eat the stuff, you can get garlic in supplement form.


Hawthorn is an herbal remedy for high blood pressure that has been used in traditional Chinese medicines for thousands of years. Decoctions of hawthorn seem to have a whole host of benefits on cardiovascular health, including reduction of blood pressure, the prevention of clot formation, and an increase in blood circulation. You can take hawthorn as a pill, a liquid extract, or a tea.

Celery Seed

Celery seed is an herb used to flavor soups, stews, casseroles, and other savory dishes. Celery has been long used to treat hypertension in China, but studies also shown that it may be effective. You can use the seeds to lower blood pressure, but you can also juice the whole plant. Celery is a diuretic, which may help explain its effect on blood pressure.

French Lavender

The beautiful, perfume-like scent of lavender is not the only useful aspect of the plant. Oil of lavender has long been used as a perfume ingredient and also to induce relaxation. The herb may also lower your blood pressure. Although not many people think to use lavender as a culinary herb, you can use the flowers in baked goods and the leaves can be used in the same way you would use rosemary.

Cat’s Claw

Cat’s claw is an herbal medicine used in traditional Chinese practice to treat hypertension as well as neurological health problems. Studies of cat’s claw as a treatment for hypertension indicate that it may be helpful in reducing blood pressure by acting on calcium channels in your cells. You can get cat’s claw in supplement form from many health food stores.

Cat’s Claw: Benefits, Side Effects, and Dosage

Cat’s claw has soared in popularity as a herbal supplement due to its alleged health benefits — though only the claims below are backed up by sufficient research.

May Boost Your Immune System

Cat’s claw may support your immune system, possibly helping fight infections more effectively.

A small study in 27 men found that consuming 700 mg of cat’s claw extract for 2 months increased their number of white blood cells, which are involved in combating infections (3).

Another small study in four men given cat’s claw extract for six weeks noted the same results (4).

Cat’s claw seems to work both by boosting your immune response and calming an overactive immune system (3, 5).

Its anti-inflammatory properties could be responsible for its immune benefits (6).

Despite these promising results, more research is needed.

May Relieve Symptoms of Osteoarthritis

Osteoarthritis is the most common joint condition in the United States, causing painful and stiff joints (7).

In one study in 45 people with osteoarthritis in the knee, taking 100 mg of cat’s claw extract for 4 weeks resulted in reduced pain during physical activity. No side effects were reported.

However, there was no change in either pain at rest or knee swelling (8).

In an eight-week study, a supplement of cat’s claw and maca root — a Peruvian medicinal plant — reduced pain and stiffness in people with osteoarthritis. In addition, participants needed pain medication less frequently (9).

Another trial tested a daily mineral supplement alongside 100 mg of cat’s claw extract in people with osteoporosis. After 1–2 weeks, joint pain and function improved compared to those not taking the supplements (10).

However, after eight weeks, the benefits were not sustained.

It should also be noted that it can be difficult to determine the specific actions of cat’s claw in studies that test multiple supplements at once.

Scientists believe that cat’s claw may ease osteoarthritis symptoms due to its anti-inflammatory properties (6, 8).

Keep in mind that more research is needed on cat’s claw and osteoarthritis (11).

May Relieve Symptoms of Rheumatoid Arthritis

Rheumatoid arthritis is a long-term autoimmune condition that causes warm, swollen, painful joints. It is increasing in prevalence in the United States, where it affects more than 1.28 million adults (12).

Some studies suggest that cat’s claw can help relieve its symptoms.

For example, a study in 40 people with rheumatoid arthritis determined that 60 mg of cat’s claw extract per day alongside regular medication resulted in a 29% reduction in the number of painful joints compared to a control group (13).

As with osteoarthritis, cat’s claw is thought to reduce inflammation in your body, easing rheumatoid arthritis symptoms as a result (6).

Although these results are promising, the evidence is weak. Larger, better-quality studies are needed to confirm these benefits.

Summary Research suggests that cat’s claw extract may aid your immune system and reduce symptoms of osteoarthritis and rheumatoid arthritis. However, more studies are needed.

Cat’s Claw


  • Cat’s claw is a woody vine that grows wild in the Amazon rainforest and other tropical areas of Central and South America. Its thorns resemble a cat’s claws.
  • The two most common species are U. tomentosa and U. guianensis. Most commercial preparations of cat’s claw contain U. tomentosa.
  • Using cat’s claw for health dates back to the Inca civilization. Its historical uses have included for contraception, inflammation, cancer, and viral infections, and to stimulate the immune system.
  • Today, cat’s claw is used as a dietary supplement for a variety of health conditions including viral infections (such as herpes and HIV), Alzheimer’s disease, cancer, arthritis, diverticulitis, peptic ulcers, colitis, gastritis, hemorrhoids, parasites, and leaky bowel syndrome.
  • The bark and root of cat’s claw are used to make liquid extracts, capsules, tablets, and tea.

How Much Do We Know?

  • There have been very few high quality clinical trials (studies done in people) of cat’s claw.

What Have We Learned?

  • There’s no conclusive scientific evidence based on studies in people that supports using cat’s claw for any health purpose.

What Do We Know About Safety?

  • Few side effects have been reported for cat’s claw when taken in small amounts.
  • Women who are pregnant or trying to become pregnant should avoid using cat’s claw because of its past use for preventing and aborting pregnancy.

Keep in Mind

  • Tell all your health care providers about any complementary or integrative health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

Cat’s Claw

  • Always check with your doctor before you use a natural product. Some products may not mix well with other drugs or natural products.

  • This product may interfere with some lab tests. Be sure to talk with your doctor about this and all drugs you are taking.

  • Be sure to tell your doctor that you take this product if you are scheduled for surgery or tests.

  • Do not use this product if you are pregnant or plan to become pregnant soon. Use birth control you can trust while taking this product.

  • Take extra care if you are taking drugs for blood pressure. These are drugs like atenolol (Tenormin), captopril (Capoten), furosemide (Lasix), and losartan (Cozaar).

  • Take extra care if you are taking drugs to thin your blood. These are drugs like warfarin (Coumadin), heparin, or enoxaparin (Lovenox).

  • Take extra care if you are taking drugs to dissolve blood clots. These are drugs like alteplase (Activase), reteplase (Retevase), or streptokinase.

  • Take extra care if you are taking drugs to help with swelling or inflammation. These are drugs like nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, ibuprofen (Advil), or naproxen (Naprosyn).

  • Take extra care if you are at a high risk for infection. This includes people who have had a transplant, are on chemo, or have an autoimmune disease.

  • You may bleed easily. Be careful to avoid injury. Use a soft toothbrush and an electric razor.

  • Take extra care and check with your doctor if you have:

    • Bleeding problems

    • Blood pressure problems

    • Cancer

Cat’s claw is a medicinal herb traditionally used to stimulate the immune system. Research has shown it may boost immune function, reduce inflammation, and even help with chemotherapy. Read on to discover the potential health benefits and adverse effects associated with this herb.

What Is Cat’s Claw?

Cat’s claw (Uncaria tomentosa) is a medicinal plant that grows in the Amazonian rainforest and other tropical areas in Central and South America. The use of the herb dates back to the Inca civilization. Indigenous cultures of South America used cat’s claw for inflammation, cancer, viral infections, ulcers, and to stimulate the immune system .

It gets its name from its thorns, which resemble the claws of cats.

Cat’s claw can refer to Uncaria tomentosa and Uncaria guianensis. Most commercial preparations such as teas, tablets, and capsules contain U. tomentosa .

The two different types of cat’s claw contain different active compounds and have different medicinal properties. Uncaria tomentosa contains more pentacyclic oxindole alkaloids (POAs), while U. guianensis is richer in tetracyclic oxindole alkaloids (TOAs) .

TOAs act on the central nervous system (brain and spinal cord), whereas POAs affect the immune system .

TOAs cancel out the effects of POAs. Therefore it is important when purchasing and consuming cat’s claw extracts to be sure that they have been tested for TOA and POA levels .

Differences between the two types are conveyed in the chemical structure. Pentacyclic alkaloids are found in the vine bark while tetracyclic alkaloids are found in the leaves and stem of the plant .

Main Beneficial Compounds of Cat’s Claw

Cat’s claw is rich in three major groups of chemical compounds: alkaloids, terpenoids, and flavonoids .

Specific compounds found in cat’s claw include:

  • Mitraphylline: an alkaloid usually found in older leaves. It has potential anticancer effects, causing cell death in sarcoma and breast cancer cells .
  • Rhynchophylline: an alkaloid isolated from the bark. It may help with convulsions, lightheadedness, numbness, and hypertension .
  • Isopteropodine: an alkaloid isolated from the leaves. It has antimicrobial properties against (Gram-positive) bacteria .
  • Uncarine (C, D, and E): a family of alkaloids found in the leaves. They have potential anti-cancer properties, inducing cell death in leukemia cells .
  • Hirsutine: an alkaloid found in the young leaves. It has antihypertensive properties, relaxing blood vessels and reducing overall blood pressure .
  • Uncaric acid: a triterpene extracted from the bark. It may be effective against Mycobacterium tuberculosis (H37Rv strain) .
  • Quinovic acid: an acid triterpene compound extracted from the bark. It may reduce heart rate .
  • Quinic acid has antioxidant properties, enhances DNA repair, and has neuroprotective effects in the brain .
  • Procyanidins: a flavonoid (phenolic compounds found in the leaves, stems, bark, and wood of U. tomentosa). It has antioxidant, anti-inflammatory, and anticancer properties .

Mechanisms of Action

Cat’s claw:

  • Decreases inflammatory molecules TNF-α and NF-κB .
  • Blocks the release of iNos, an enzyme that creates free radicals as part of the immune response .
  • Blocks the release of COX-1 and COX-2, enzymes that play crucial roles in inflammation and pain .

Health Benefits

Possibly Effective for:

Cat’s claw’s anti-inflammatory effects have been commonly used to treat both rheumatoid arthritis and osteoarthritis .

In a clinical trial on 40 rheumatoid arthritis patients, cat’s claw combined with conventional treatments (sulfasalazine/hydroxychloroquine) reduced tender and painful joints .

In another trial of 45 people with knee osteoarthritis, one week of cat’s claw reduced pain associated with activity. In another trial on 95 people, a dietary supplement with 300 mg cat’s claw and 1500 mg maca improved joint pain, stiffness, and function as effectively as the more common supplement glucosamine sulfate .

Cat’s claw extract increased IGF-1 levels in human cartilage cells, which might help to maintain cartilage health and prevent cartilage breakdown. In animal and cell-based studies, cat’s claw blocked IL-1β and other inflammatory molecules that suppress IGF-1 production .

The different compounds in cat’s claw supposedly act together to achieve these effects .

Mitraphylline blocks the release of inflammatory molecules such as IL-1, IL-4, and IL-17, and TNF-alpha .

Other pentacyclic oxindole alkaloids cause the release of a currently unidentified immune regulating factors that may reduce arthritic joint pain .

Quinic acid decreases inflammatory molecules like NF-κB .

Although limited, the existing evidence suggests that cat’s claw may help with the symptoms of both rheumatoid arthritis and osteoarthritis. You may discuss with your doctor if it could be useful as an adjuvant therapy in your case. Never take cat’s claw in place of what your doctor recommends or prescribes for arthritis.

Insufficient Evidence for:

In a study of 31 volunteers with cold sores (herpes labialis), cat’s claw was more effective in reducing symptoms such as swelling, skin reddening, and pain compared to prescription antiviral drug Acyclovir .

In a cell-based study, cat’s claw extract prevented the spread of the herpes virus by preventing it from attaching to cells .

In another trial on 261 people, immunostimulation with a natural product containing cat’s claw and other herbal extracts reduced the incidence of anal warts (caused by infections with the human papillomavirus) after a surgical procedure .

Cat’s claw also prevented immune cells from being infected with dengue virus and reduced inflammatory cytokines TNF-alpha and IFN-alpha .

Although the results are promising, two clinical trials and some animal and cell-based research cannot be considered sufficient evidence to support the use of cat’s claw for viral infections. Further clinical research is needed.

2) Add-On to Anticancer Therapy

In a study of 40 breast cancer patients undergoing chemotherapy, 300 mg cat’s claw extract prevented a decrease in white blood cells (neutropenia) and repaired DNA damage. However, the same dose was ineffective in another trial on 43 people with colorectal cancer .

In a clinical trial on 51 people with advanced cancer, cat’s claw reduced fatigue and improved quality of life .

In rats who received chemotherapy, cat’s claw increased white blood cell count and helped repair damaged DNA .

Cat’s claw also stimulates the growth of progenitor cells in mice, which can replace damaged cells and reduce the damaging effects of chemotherapy .

Again, 3 clinical trials (with mixed results) and some animal research are insufficient to claim that cat’s claw may help fight cancer. Larger, more robust clinical trials are needed.

3) Stomach and Gut Inflammation

Cat’s claw can cleanse the digestive tract and is claimed to help treat inflammatory gut disorders including :

  • Crohn’s disease
  • Colitis
  • Gastritis
  • Diverticulitis
  • Stomach ulcers
  • “Leaky gut”

In a clinical trial on 50 people with gum inflammation, a gel with cat’s claw was as effective as an antifungal (miconazole) at reducing the counts of infectious yeasts .

Cat’s claw protected against stomach inflammation in rats and prevented TNF-α production and cell death .

Bacterial toxins also cause the release of inflammatory molecules like NF-κB and TNF-α. Cat’s claw blocked the release of these inflammatory molecules in mice .

Inflammation of the gut is also caused by toxic free radicals (peroxynitrite). Cat’s claw broke down free radicals and reduced cell death caused by gut bacterial toxins .

While only a small trial investigated cat’s claw for gum inflammation, its effects on inflammation of the digestive system have only been tested in animals. Further clinical research is required to confirm these preliminary findings.

4) Boosting the Immune System

Cat’s claw may enhance the immune system by increasing the levels of key immune cells (T helper and B cells) and the activity of granulocytes .

In a small trial on 23 healthy volunteers, a cat’s claw extract enhanced the immune effects of a vaccine against pneumococcal infections. The extract increased the relative abundance of immune cells (lymphocytes) and prolonged the antibody titer response of the vaccine .

Again, only a small clinical trial and some animal and cell-based research have investigated this potential benefit of cat’s claw. More clinical trials on larger populations are warranted.

5) High Blood Pressure

Two different traditional Chinese medicines with cat’s claw and other herbs (Jiangzhuo Qinggan and Qian Yang He Ji) lowered blood pressure in clinical trials on almost 300 people. However, another remedy combining cat’s claw and potato orchid (Gastrodia) was ineffective and used as the negative control in another trial on 79 people .

Cat’s claw contains a compound called hirsutine that reduces blood pressure. It acts as a calcium channel blocker in the heart and blood vessels, which slows down the heart rate and relaxes the blood vessels .

Because the only clinical trials tested herbal mixes containing cat’s claw and other extracts (with mixed results), we cannot establish if the effects observed were due to this specific ingredient, More clinical trials using cat’s claw alone are needed to shed some light on this potential use.

Animal and Cell Research (Lack of Evidence)

No clinical evidence supports the use of cat’s claw for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies should not be interpreted as supportive of any health benefit.


Cat’s claw has been traditionally used to treat diabetes .

Its extract reduced blood sugar levels and inflammation and prevented diabetes in mice whose insulin-releasing cells (beta-cells) were damaged .

Protecting Red Blood Cells

Cat’s claw protected red blood cells (RBCs) from damage due to toxins and reduced oxidative stress. It also prevented cell death and oxidative stress in RBCs exposed to pesticides .

Antioxidant and Anti-inflammatory

Procyanidins and other polyphenols in cat’s claw scavenged and remove oxidative radicals in cell-based studies .

Cat’s claw also blocked the production of the inflammatory cytokine TNF-α and prevented cell death .

Side Effects and Precautions, Limitations & Dosage

This list does not cover all possible side effects. Contact your doctor or pharmacist if you notice any other side effects.

Call your doctor for medical advice about side effects. In the US, you may report side effects to the FDA at 1-800-FDA-1088 or at In Canada, you may report side effects to Health Canada at 1-866-234-2345.

Cat’s claw is generally considered safe. The main side effects reported in clinical trials were usually mild and included :

  • Dizziness
  • Upset stomach
  • Skin rash
  • Nausea
  • Diarrhea

Pregnant women should avoid using cat’s claw because of the herb’s potential to cause abortion .

Because cat’s claw seems to enhance the immune response by increasing the activity of immune cells, this supplement may increase the symptoms of autoimmune disorders. People with autoimmune conditions should be especially cautious with cat’s claw and never take it without discussing it with their doctors .

Cat’s claw decreased molecules that activate clotting (IL-1α, 1β, 4, 17, and TNF-α). People with blood clotting disorders or on blood thinners should avoid cat’s claw to reduce the risk of bleeding and bruising .

When cat’s claw was used in combination with some HIV treatments like protease inhibitors (atazanavir, ritonavir, and saquinavir), it increased their toxicity .


Few high-quality clinical trials with cat’s claw have been conducted in humans. More studies are needed to confirm its health benefits.

Cat’s claw was sometimes tested as part of multi-herbal complexes, making its specific contribution to the effects observed difficult to estimate.


Because cat’s claw is not approved by the FDA for any conditions, there is no official dose. Users and supplement manufacturers have established unofficial doses based on trial and error. Discuss with your doctor if cat’s claw may be useful in your case and which dose you should take.

Clinical trials have used between 80 – 350 mg of cat’s claw extract. These extracts usually contained a certain amount of pentacyclic oxindole alkaloids, rather than tetracyclic oxindole alkaloids.

Experiences with Cat’s Claw

The opinions expressed in this section are solely those of cat’s claw users, who may or may not have medical or scientific training. Their reviews do not represent the opinions of SelfDecode. SelfDecode does not endorse any specific product, service, or treatment.

Do not consider user experiences as medical advice. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare providers because of something you have read on SelfDecode. We understand that reading individual, real-life experiences can be a helpful resource, but it is never a substitute for professional medical advice, diagnosis, or treatment from a qualified healthcare provider.

Several users reported satisfactory results when using cat’s claw for arthritis, digestive inflammation, and infections.

A doctor claimed using cat’s claw on 150 patients during the last 4 years and obtaining better results than with any other available products.

One user noted that cat’s claw increased the severity of their headache and fatigue, which they linked to a die-off effect.

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