Devil’s claw is a plant native to the African continent. Its name is derived from the Greek word harpagophytum, meaning the “hook plant.” This name is well suited, as its most notable of characteristics are the hook-like projections protruding from its fruit. Many other plants have similar appendages on their fruits and seeds. These “hooks” are both a defense and reproductive mechanism; by discouraging the consumption of the plant, and by becoming easily entangled in the fur of animals in order to spread the seeds. 
Natives of South Africa used devil’s claw as a pain and fever reducer, as well as for uses concerning the digestive tract. The medicinal activity of devil’s claw was unknown in Europe until early colonists brought the herb back to their countries of origin where its use was employed therapeutically for various arthritic conditions.
Modern uses of devil’s claw include treatments of joint pain, whether caused by osteoarthritis, gout, or rheumatoid arthritis. Additionally, the herb provides some relief for connective tissue (muscle, tendons, and ligaments) pain. As a bitter herb, it can be used as a digestive assistant and to calm mild stomach upset due to indigestion.
The most biologically active component of the devil’s claw plant is the ‘tuber’, or root. The tuber is quite large and is often chopped and dried prior to processing. Active constituents located in the tuber include; iridoid glycosides, the principle one being harpagoside. Other iridoid glycosides receiving praise in study include harpagide and procumbide for their contributory effects to the herb’s medicinal efficacy.  Active constituents worth mention include phenylethanol derivatives (i.e. verbascoside and isoaceteoside) and stachyose, an oligosaccharide. 
Devils Claw Uses
Due to the anti-inflammatory properties of its many chemical components, the principle use for devil’s claw remains within the arenas of inflammatory conditions.  Certain constituents have been shown to inhibit two potent inflammatory enzymes; COX-2, and nitric oxide synthestase.  Other research has shown that in addition to these enzymes, devil’s claw may inhibit the lipoxygenase pathway; a potent pro-inflammatory enzymatic pathway.  However, extensive research has not shown any significant effects upon the arachidonic acid system, another less potent inflammatory pathway.  More research is necessary.
In one study, researchers treated patients who had rheumatoid arthritis with devil’s claw for a period of 2months.  These patients exhibited significant decreases in the intensity of their pain, as well improved joint mobility; two factors which are standard measures of improvement for any arthritis drug. A shorter duration study found comparable effects regarding pain relief (in patients with rheumatoid arthritis) after a course of only 10 days of treatment with devil’s claw.  When examined for its effects on muscle pain, a 4-week trial treated patients who had muscle tension resulting in neck, back, and shoulder pain.  Compared to the placebo arm of the study, patients treated with devil’s claw had a significant reduction in pain.
Other research points to a role for devil’s claw in certain cardiovascular systems. One particular constituent of the herb, harpagide appears to effectively slow the heart rate and improve the strength of contractions when given in relatively low doses. On the contrary, higher doses of the herb will weaken the heart muscle and interfere with circulation to the heart itself.  Another constituent, harpagoside, has been demonstrated to have antiarrhythmic effects on the heart as well.  These effects are extremely beneficial in several types of cardiovascular conditions; more research continues into this area to determine the full effects of devil’s claw on the cardiovascular system.
Standard dosing of devil’s claw is roughly 750 milligrams of dried herb, standardized to 3% iridoid glycosides, administered three times daily for general treatment (e.g. joint pain). Other sources usually recommend dosages ranging from 1000 to 4500 milligrams per day, for maximum effectiveness. 
Devils Claw Side Effects
The safety of devil’s claw appears consistent; with no evidence in medical literature of toxicity, even at doses several times higher than what is typically recommended.  When taken by mouth, devil’s claw appears to be well tolerated. The most commonly reported side effects (according to one study measuring side effects of the herb) are loose stools, which may affect some 8% of those taking it. 
Limited case reports (individual patient experiences) have recorded side effects such as nausea, vomiting, and abdominal pain. Complaints of painful menses have arisen as well.  Other case reports detail headache, ringing in the ears, loss of appetite, and blunted taste, caused by ingesting the herb.  The extent of these reported side effects is currently under clinical testing.
Devils Claw Interactions
No interactions with other herbs or supplements are known, nor with foods or clinical lab tests. 
Devils Claw Drug Interactions
Taken with antacids, devil’s claw may negate the effects of these medicines; due the possibility that devil’s claw may increase stomach acid secretion. 
Devil’s claw may lower blood sugar levels, thereby increasing the effectiveness of diabetes medicines. Patients may need to closely monitor blood sugar levels if taking devil’ claw in conjunction with certain diabetes medications. 
The effectiveness of ulcer medications may be compromised by devil’s claw, again, as it may increase the output stomach acid. 
Devil’s claw may increase the effectiveness of anticoagulation medicines such as Warfarin (Coumadin). Devil’s claw should be avoided, or used with extreme caution, by those taking this medicine. 
Devils Claw Disease Conditions
People that have ulcers, liver or kidney disease, young children, and pregnant or nursing women should not take devil’s claw until absolute safety is known.
Because of the effect of devil’s claw on the cardiovascular system, individuals diagnosed with cardiovascular conditions should use this herb with caution and obtain physician recommendations.
As mentioned previously, devil’s claw may affect diabetes drugs. Therefore, people with this condition should use devil’s claw with extreme caution.
Devil’s claw may increase bile production and worsen gallstone problems.  Similarly, those with ulcers may want to avoid the use of devil’s club due to the herb’s effect on raising stomach acid production. 
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