Devil's Claw

Other Name(s):

Devils Claw, Devil's Claw Root, Garra del Diablo, Grapple Plant, Griffe du Diable, Harpagophyti Radix, Harpagophytum, Harpagophytum procumbens, Harpagophytum zeyheri, Racine de Griffe du Diable, Racine de Windhoek, Teufelskrallenwurzel, Uncaria procumbens, Wood Spider.

Overview

Devil's claw is an herb. The botanical name, Harpagophytum, means “hook plant” in Greek. This plant, which is native to Africa, gets its name from the appearance of its fruit, which is covered with hooks meant to attach onto animals in order to spread the seeds. The roots and tubers of the plant are used to make medicine.

Devil's claw is used for “hardening of the arteries" (atherosclerosis), arthritis, gout, muscle pain (myalgia), back pain, tendonitis, chest pain, gastrointestinal (GI) upset or heart burn, fever, and migraine headache. It is also used for difficulties in childbirth, menstrual problems, allergic reactions, loss of appetite, and kidney and bladder disease.

Some people apply devil's claw to the skin for injuries and other skin conditions.

How does it work?

Devil's claw contains chemicals that might decrease inflammation and swelling and resulting pain.

SLIDESHOW

Slideshow: Exercises for Knee Osteoarthritis and Joint PainSee Slideshow

Uses & Effectiveness

Possibly Effective for...

  • Back pain. Taking devil's claw by mouth seems to reduce low-back pain. Devil's claw seems to work about as well as some non-steroidal anti-inflammatory drugs (NSAIDs).
  • Osteoarthritis. Taking devil's claw alone or along with nonsteroidal anti-inflammatory drugs (NSAIDs) seems to help decrease osteoarthritis-related pain. Some evidence suggests that devil's claw works about as well as diacerhein (a slow-acting drug for osteoarthritis that is not available in the U.S.) for improving osteoarthritis pain in the hip and knee after 16 weeks of treatment. Some people taking devil's claw seem to be able to lower the dose of NSAIDs they need for pain relief. This evidence comes from a study that used a specific powdered devil's claw root product (Harpadol, Arkopharma) containing 2% of the devil's claw ingredient harpagoside (9.5 mg/capsule) and 3% total iridoid glycosides (14.5 mg per capsule). Another specific devil's claw extract (Doloteffin, Ardeypharm) 2400 mg/day providing 60 mg/day of the harpagoside ingredient has also been used.

Insufficient Evidence to Rate Effectiveness for...

  • Rheumatoid arthritis (RA). Early research suggests that taking devil's claw extract by mouth might not improve RA.
  • Upset stomach.
  • Loss of appetite.
  • High cholesterol.
  • Gout.
  • Muscle pain.
  • Migraine headache.
  • Skin injuries and conditions.
  • Other conditions.
More evidence is needed to rate devil's claw for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate(detailed description of each of the ratings).

Side Effects

Devil's claw isPOSSIBLY SAFEfor most adults when taken by mouth in appropriate doses for up to a year. The most common side effect is diarrhea. About 8% of the people participating in one research study developed diarrhea. Other possible side effects include nausea, vomiting, abdominal pain, headaches, ringing in the ears, loss of appetite, and loss of taste. It can also cause allergic skin reactions, menstrual problems, and changes in blood pressure.

However, not enough is known about the safety of using devil's claw long-term or applying it to the skin.

QUESTION

What joints are most often affected by osteoarthritis?See Answer

Special Precautions & Warnings

Pregnancy and breast-feeding: Devil's claw isPOSSIBLY UNSAFE. It might harm the developing fetus. Avoid use in pregnancy. It is also best to avoid using devil's claw while breast-feeding. Not enough is known yet about its safety during breast-feeding.

Heart problems, high blood pressure, low blood pressure: Since devil's claw can affect heart rate, heartbeat, and blood pressure, it might harm people with disorders of the heart and circulatory system. If you have one of these conditions, talk with your healthcare provider before starting devil's claw.

Diabetes: Devil's claw might lower blood sugar levels. Using it along with medications that lower blood sugar might cause blood sugar to drop too low. Monitor blood glucose levels closely. Your healthcare provider might need to adjust your dose of diabetes medications.

Gallstones: Devil's claw might increase bile production. This could be a problem for people with gallstones. Avoid using devil's claw.

Peptic ulcer disease (PUD): Since devil's claw might increase the production of stomach acids, it might harm people with stomach ulcers. Avoid using devil's claw.

Interactions


Medications changed by the liver (Cytochrome P450 2C19 (CYP2C19) substrates)Interaction Rating:ModerateBe cautious with this combination.Talk with your health provider.

有些药物通过th改变和分解e liver. Devil's claw might decrease how quickly the liver breaks down some medications. Taking devil's claw along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking devil's claw talk to your healthcare provider if you take any medications that are changed by the liver.

Some medications that are changed by the liver include omeprazole (Prilosec), lansoprazole (Prevacid), and pantoprazole (Protonix);diazepam(Valium); carisoprodol (Soma); nelfinavir (Viracept); and others.


Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates)Interaction Rating:ModerateBe cautious with this combination.Talk with your health provider.

有些药物通过th改变和分解e liver. Devil's claw might decrease how quickly the liver breaks down some medications. Taking devil's claw along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking devil's claw talk to your healthcare provider if you take any medications that are changed by the liver.

Some medications that are changed by the liver include diclofenac (Cataflam,Voltaren),ibuprofen(Motrin),meloxicam(Mobic), and piroxicam (Feldene); celecoxib (Celebrex); amitriptyline (Elavil); warfarin (Coumadin); glipizide (Glucotrol); losartan (Cozaar); and others.


Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)Interaction Rating:ModerateBe cautious with this combination.Talk with your health provider.

有些药物通过th改变和分解e liver. Devil's claw might decrease how quickly the liver breaks down some medications. Taking devil's claw along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking devil's claw, talk to your healthcare provider if you are taking any medications that are changed by the liver.

Some medications changed by the liver include lovastatin (洛伐他汀), ketoconazole (Nizoral), itraconazole (Sporanox), fexofenadine (Allegra)、三唑仑(Halcion), and many others.


Warfarin (Coumadin)Interaction Rating:ModerateBe cautious with this combination.Talk with your health provider.

Warfarin (Coumadin) is used to slow blood clotting. Devil's claw might increase the effects of warfarin (Coumadin) and increase the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.


Medications moved by pumps in cells (P-glycoprotein Substrates)Interaction Rating:MinorBe cautious with this combination.Talk with your health provider.

Some medications are moved by pumps into cells. Devil's claw might make these pumps less active and increase how much of some medications get absorbed by the body. This might increase the side effects of some medications.

Some medications that are moved by these pumps include etoposide,paclitaxel, vinblastine, vincristine, vindesine, ketoconazole, itraconazole, amprenavir, indinavir, nelfinavir, saquinavir, cimetidine, ranitidine, diltiazem, verapamil, corticosteroids,erythromycin, cisapride (Propulsid), fexofenadine (Allegra), cyclosporine, loperamide (Imodium), quinidine, and others.


Medications that decrease stomach acid (H2-blockers)Interaction Rating:MinorBe cautious with this combination.Talk with your health provider.

Devil's claw might increase stomach acid. By increasing stomach acid, devil's claw might decrease the effectiveness of some medications that decrease stomach acid, called H2-blockers.

Some medications that decrease stomach acid include cimetidine (Tagamet), ranitidine (Zantac), nizatidine (Axid), and famotidine (Pepcid).


Medications that decrease stomach acid (Proton pump inhibitors)Interaction Rating:MinorBe cautious with this combination.Talk with your health provider.

Devil's claw might increase stomach acid. By increasing stomach acid, devil's claw might decrease the effectiveness of medications that are used to decrease stomach acid, called proton pump inhibitors.

Some medications that decrease stomach acid include omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium).

Dosing

The following doses have been studied in scientific research:

BY MOUTH:

  • For osteoarthritis: A specific powdered devil's claw root product (Harpadol, Arkopharm) dosed at 2.6 grams/day. This dose provides a total of 57 mg of harpagoside, one of the active ingredients, and 87 mg of total iridoid glycosides, another active ingredient. Another specific devil's claw extract (Doloteffin, Ardeypharm) dosed at 2400 mg/day has also been used.
  • For back pain: A specific devil's claw extract (Doloteffin, Ardeypharm) that provides 50-100 mg of the active ingredient harpagoside daily.

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