Cat's Claw Summary:
Cat’s claw, otherwise known as Uña de gato, is best known for its benefits on the immune system, as an adjunctive therapy for cancer, and as a natural anti-inflammatory for conditions like arthritis, and inflammatory bowel disorders.
As an anticancer agent, it works by providing a protective effect on cells, thus preventing and repairing cellular damage caused by free radical species like TNF-a and other cytokine insult. SOme of the compoenent in cat's claw have a direct effect on DNA repair. It's when this DNA is damaged that cancer can occur in the first place, so by preventing and protecting the cellular DNA in the body, cancer risk can be reduced.
Cat's claw also has the ability to increase the important immune cells of the body, which are tasked with the job of cleaning up invading pathogens, but also must identify and destroy cancerous or other dysfunctional cells in the body. With modern cancer therapies, this part of the immune system is damaged, and once they reach a certain level the chemotherapy must be stopped. In this way cat's claw has been suggested to increase the effectiveness of chemotherapeutic drugs, so that this cutoff level is not reached as quickly, if at all. This allows the chemotherapy drugs to be used longer and with more intensity, which may then improve their effectiveness in destroying the cancer.
Cat's claw is also suggested to reduce many of the factors known to cause inflammation in the body. In the short term, inflammation is beneficial to recover from damage, but when long term inflammation persists, it can lead to many negative effects throughout the body. Some of the inflammatory factors that cats claw inhibits, are also closely linked with the development and growth of cancer cells. cats claw is an extremely valuable herb in regards to cancer treatment, and prevention, especially in conjunction with modern therapies, It is also useful then for chronic inflammatory diseases, such as irritable bowel syndrome, Crohns, arthritis, leaky gut syndrome, and Alzheimers.
Bark, roots, leaves
1 cup (250 mL) twice a day
Adding a small amount of lemon juice while decocting helps extract the alkaloids that are responsible for much of the medicinal action of this plant.
Liquid Extract (1:1)
- Immune disorders
- Rheumatic disorders
- Some viral infections
- Herpes zoster
- Human Immunodeficiency Virus (HIV)
- Some bacterial infections
- Crohn's disease
- Leaky gut syndrome
- To help prevent strokes
- Prevent heart attacks
- Reduce blood clots
- Irritable bowel syndrome
- To improve general overall health
- Uña De Gato
- Cat’s Claw
- Garbato Casha
- Tambor huasca
- Uña huasca
- Una de gavilan
- Hawks claw
Cat’s claw has been used by various Amazonian Indigenous cultures including Aguaruna, Asháninka, Cashibo, Conibo, and Shipibo tribes for at least the past 2000 years [1, 28, 29, 30].
The Asháninka Indian tribe of Peru have the longest recorded history of use for this herb. They have used cat’s claw to treat asthma, urinary tract inflammation, arthritis, rheumatism, bone pain, recovery from childbirth, as a kidney cleanser, as a vulnerary for deep wounds, control general inflammation, gastric ulcers, and cancer. [1, 28].
Other Peruvian indigenous cultures used cat’s claw to treat tumors, Inflammation, rheumatism, diabetes, urinary tract cancer in females, hemorrhages, menstrual irregularities cirrhosis, fevers, abscesses, gastritis, rheumatism, gastritis, abscesses, tumors, gastric ulcers, viruses and to normalise the body. [1, 28, 30].
Cat claw has reportedly been used as a contraceptive but several different tribes in Peru. They used very concentrated and large doses to achieve this. The Asháninka for example would boil 5-6 kg (12 pounds) of the root in water until it has been reduced to around 250 ml (1 cup), and consumed by females during menstruation periods for 3 months. Supposedly this will cause sterility for 3 or 4 years. .
Cat’s claw is a large woody vine found in the Amazon rainforest. Its characterizing feature are the curved hook like thorns found along the vine itself. These are shaped in a curved hook shape that resembles the claws of cats which is where it gets its common name.
Cat's claw grows up to 30m up into the Amazonian canopy.
There are 2 commonly used species, Uncaria tomentosa, and Uncaria guianensis. The 2 can be told apart by their flowers. Uncaria tomentosa sports small, yellowish-white flowers, and Uncaria guianensis has reddish-orange flowers and its thorns are generally more curved. Both are used interchangeably as medicine however.
It is important to note that there are a few other species of plants referred to commonly as Cat’s claw or Uña de Gato that are completely unrelated. In fact several of these plants have known toxic effects. This is why knowing the botanical name is important when using herbs as medicine, and why purchasing these herbs from a reliable and trustworthy herbalist is very important.
Habitat, Ecology, Distribution:
Cat’s claw is indigenous to the Amazon rainforest and can be found all over Central and South America including Peru, Brasil, Guatemala, Colombia, Suriname, Ecuador, Costa Rica, Trinidad, Guyana, Panama, and Venezuela.
Most of the Uncaria genus of the Rubiaceae family have been used as medicine, and can be found throughout the tropics of Southern Asia, South America, and Africa. .
Harvesting, Collection, and Preparation:
Still compiling research.
Cat’s claw contains a group of chemicals referred to as oxindole alkaloids. This class of chemicals have been documented to produce immune-stimulant, antioxidant, antineoplastic, and anti-leukemic actions. [1, 13-15].
Some of the research conducted through the past 30 years on this plant have been market funded, and has resulted in some confusion regarding these oxindole alkaloids. It has been circulating that this plant contains both “good alkaloids” that stimulate the immune system, as well as “bad alkaloids” which have negative effects on the immune system. The good ones were reportedly pentacyclic alkaloids, and the bad were suggested to be tetracyclic alkaloids. This has been proven to be wrong information however, as both alkaloids are indeed contained in both species of cat’s claw, and in different ratios, however both alkaloids were shown to produce immunostimulating effects instead. On top of these, both alkaloids have been shown to produce anti cancer benefits as well .
Cat’s claw also contains a group of chemicals called quinovic acid glycosides which have well documented anti-inflammatory and antiviral actions.
Also contained within cat’s claw are a series of antioxidant chemicals such as tannins, catechins, and procyanidins. [1, 8].
Plat sterols contained within cat’s claw includes beta-sitosterol, stigmasterol, and campesterol.
Caroxyl alkyl esters contained within cat's claw provide some of the immuno-stimulant, anti inflammatory, cell repairing, and anticancer benefits.
Cat's claw contains ajmalicine, akuammigine, campesterol, catechin, carboxyl alkyl esters, chlorogenic acid, cinchonain, corynantheine, corynoxeine, daucosterol, epicatechin, harman, hirsuteine, hirsutine, iso-pteropodine, loganic acid, lyaloside, mitraphylline, oleanolic acid, palmitoleic acid, procyanidins, pteropodine, quinovic acid glycosides, rhynchophylline, rutin, sitosterols, speciophylline, stigmasterol, strictosidines, uncarine A thru F, and vaccenic acid .
Pharmacology and Medical Research:
Alzheimer's is a neurodegenerative disorder characterized by the accumulation of extracellular beta-amyloid plaques leading to eventual death of the synapse. The symptoms of Alzheimer's includes a progressive loss of learning, hearing, memory, and other cognitive decline. Current treatments of Alzheimer's includes the use of acetylcholinesterase inhibitors, and antagonists of N-Methyl-D-aspartate receptors in an attempt to slow down the progression of this debilitating disease.
In Chinese medicine, a related species of cat's claw (Uncaria rhychophylla) has been used to treat headaches, dizziness, tremors, and hypertension induced convulsion [19-21]. These are all symptoms of Alzheimer's, and other age related cognitive decline. Some recent studies on this plant have indicated that it is effective for the inhibition of beta-amyloid fibril formation, as well as the ability to disassemble current beta-amyloid fibrils . It has also been shown to produce significant anti acetylcholinesterase activity . Cat's claw has been shown in mice models to reverse cognitive deficits induced by D-galactose, which is used as a model to study Alzheimers . A study done investigating the compounds responsible for these known beneficial effects on Alzheimer's found that the main components responsible are rhynchophylline and isorhynchophylline . The results showed that these 2 chemicals significantly decreased beta-amyloid induced cell death, calcium overloading, and tau protein hyperphosphorylation in PC12 cells. . PC12 cells are used as a model for studying Alzheimer's in vitro.
Some of the effects noted with cats claw including its potent antioxidant, and vasodilatory actions in the brain may also be of significant benefit for treating or preventing Alzheimer's or other forms of dementia as well.
Breast cancer, is the most frequent neoplasm affecting women worldwide, but is most prevalent in developed countries. . Roughly 70% of breast cancers express estrogen or progesterone receptors . Women with breast cancer have been shown to present an increase in blood concentrations of oxidized substances, which may have derived from lipid peroxidation, proteins, and DNA [11,12]. Cat's Claw does in fact contain a significant amount of antioxidant compounds , but this form of treatment towards cancer is controversial, as the performance of antioxidants in vivo depends on the type of free radicals formed, and it is possible that some antioxidants will protect the cells, but also possible that they will not do anything for that form of free radical damage . A study done comparing the effectiveness of various extracts of cat's claw against Walker-256 tumor model found that the extract containing all fractions of chemicals had more significant effects than did the extracts containing much higher alkaloid content, and extract containing more non-alkaloid content. These researcher suggested these effects are due to the additional antioxidant value of the non-alkaloid fractions in combination with the alkaloid content . This data suggests that the antioxidant components of cat's claw are indeed active in the free radicals associated with at least some cancer cell lines.
Modern cancer treatment usually involves chemotherapy which brings with is a wide range of negative side effects such a leucopenia (low white blood cells), and neutropenia (low neutrophils). When these cells are low, our immune system will be significantly lowered with them. .
Some of the older research has has shown that cat's claw treatment along with more modern cancer treatments such as radiation and chemotherapy have resulted in lower side effects , to this form of treatment which may include hair loss, weight loss, nausea, and secondary infections. It has been suggested that this reduction in side effects are due to cats claws ability to support and repair cellular DNA damage [1, 6], and prevent cells from mutating. It also helps to prevent the loss of white blood cells, which is a common result of chemotherapy. . Cat's claw modulates various levels of the immune system including the proliferation of both T and B lymphocytes, as well as various cytokines including TNF-a . It is also directly myelo stimulating, which acts through myelopoiesis and colony-stimulating factors (G-CSF) to benefit neutropenia (low neutrophils) [6,9]. In chemotherapy, the cytotoxic effects are not limited to cancerous cells, but kill other cells in the body. When neutrophil content is lowered below 500 cells/mm3 treatment is generally discontinued . Therefore neutrophils tend to be the limiting factor in the success of the chemotherapy, and preventing and managing neutropenia induced by chemotherapy should be considered a top priority . A 300 mg dry extract of Cat's Claw has been found to be effective in reducing the incidence and severity of neutropenia in a recent clinical trial. In this study it was noted that by the end of the treatment, patients treated with Cats claw extract has neutrophil counts twice that of the control group .
This clear immunostimulating benefit offered by cat’s claw may prove to be a very useful adjunct treatment with modern cancer therapy for its ability to improve the immune system in immunocompromised patients due to malnutrition, stress, and medication side effects.
Other alkaloids contained within cat's claw have been shown to produce antihypertensive effects. These alkaloids includes rhynchophylline, hirsutine, and mitraphylline. These alkaloids have been shown to produce vasodilatory actions.
Rhynchophylline has been found to prevent blood clots in blood vessels, dilate peripheral blood vessels, lower heart rate, lower cholesterol. .
Many of cats claws anti inflammatory actions can be attributed to its antioxidant compounds, and plant sterols . It has been demonstrated to offer antinflammatory benefits when it was shown to prevent or modulate lung damage induced by ozone in vivo . The antinflammatory actipon is suggested to be through a variety of factors, including the modulation of TNF synthesis, via NF-kb inhibition [29, 31-33]. A study investigating the more specific effects that cats claw has on cystitis (inflammation of the urinary bladder), found it to be effective in reducing urethral damage, reducing visceral pain, and downregulating several inflammatory factors .
Various compounds contained in the plant called quinovic acid glycosides have also been shown to benefit inflammation. In fact it is these compounds that have been suggested to be the most potent anti inflammatories contained in the plant. These studies back up much of the traditional use for this plant or such conditions as arthritis, rheumatism, gastrointestinal inflammations such as irritable bowel syndrome and crohn's disease. . Most likely however, based on the wide range of anti inflammatory effects, and a higher amount of anti inflammatory action noted in the whole plant extract, these actions are the result of synergy found throughout the entire plant, and should not as such be considered the result of just one isolated chemical or class of chemicals. If using cat's claw for inflammation, use the entire plant extract. [16, 17].
The antioxidant effects of a cat's claw hydroalcoholic extract were noted to be most effective when compared to extracts containing mostly alkaloid components, and a separate extract containing mostly non-alkaloid components . This suggests a strong synergy within the plant.
The quinovic acid glycosides have been shown to provide significant benefit in treating stomach ulcers in rats .
Still compiling research
Many of the alkaloids contained in cats claw including the oxindole alkaloids have been found to produce immunostimulating benefits. .
Pteropodine and isopteropodine have been suggested to provide positive modulatory benefits on brain neurotransmitters such as 5-HT(2) receptors. This suggests a mechanism of action for many of cats claws uses for conditions such as depression, anxiety, eating disorders, chronic pain, and obesity. .
Cat's claw is generally very safe to consume, however due to its well documented immunostimulating effects, it is recommended not to consume this herb before or following a bone marrow, or organ transplant or a skin graft as this may increase the chances of rejection. Also due not take this herb if you are on any immune suppressing medications as cat's claw may counteract or reduce the effectiveness of these medications. This theory has not been proven but until it is proven otherwise should be assumed that this will happen.
Some of the traditional use of this plant suggest antifertility effects and therefore should not be consumed by anybody trying to conceive. This effect has not been proven however and very little scientific research has been conducted in this area. Do not rely on this herb to produce antifertility actions even in large doses.
Cat's claw contains anticoagulant effects as well and therefore should not be taken by those on blood thinners such as coumadin, and discontinue use at least a week prior to any surgery.
Large doses (3-4g at a time) of cat's claw have been reported to produce some gastrointestinal discomfort. These effects tend to disappear after continued use however if they do not go away after 3-4 days, reduce the dose or discontinue use.
Traditional Chinese Medicine
(Chinese species: Uncaria rhyncophylla)
Taste: Sweet 
Energy: Cold 
Channels: Liver, pericardium 
Actions: Clears heat, Expels wind, extinguishes internal wind, calms and anchors the shen, settles tremors, anchors the yang .
Indications: Headaches, irritability, red eyes, vertigo, fever, dizziness, seizures. Acceptable to use during pregnancy. .
Dose: 6-15g decocted 10 mins 
In Chinese medicine, the related species Uncaria rhynchophylla is considered to act on the liver, and expell wind conditions. It is often used for central nervous system conditions such as tremor, seizure, and epilepsy .
Cat's claw has been suggested to provide protection from non steroidal anti inflammatory drugs such as ibuprofen in the gastrointestinal wall.
The Sunlight Experiment
Updated March 2017
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