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Devil's Claw

What is it?

Devil's claw (Harpagophytum procumbens) is an herb. It has been used by mouth for back pain and arthritis, but there is little evidence to support these uses.

Devil's claw is native to south Africa, including the Kalahari Desert, where it's been used traditionally for many conditions. Devil's claw contains chemicals that might decrease swelling. Because of this, it is often used to treat conditions that involve both pain and inflammation.

Devil's claw is most commonly used for back pain and osteoarthritis. It is also used for rheumatoid arthritis (RA) and other conditions, but there is no good scientific evidence to support these uses. There is also no good evidence to support using devil's claw for COVID-19.

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for DEVIL'S CLAW are as follows:

Possibly effective for...

  • Back pain. Taking devil's claw by mouth seems to reduce lower back pain. Devil's claw seems to work about as well as some non-steroidal anti-inflammatory drugs (NSAIDs).
  • Osteoarthritis. Taking devil's claw by mouth alone, with other ingredients, or along with nonsteroidal anti-inflammatory drugs (NSAIDs) seems to help reduce osteoarthritis pain. Some people taking devil's claw seem to be able to lower the dose of NSAIDs taken for pain relief.
There is interest in using devil's claw for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.

Is it safe?

When taken by mouth: Devil's claw is possibly safe for most adults when taken for up 12 weeks. The most common side effects are diarrhea and indigestion. Devil's claw may also cause allergic skin reactions.

When applied to the skin: There isn't enough reliable information to know if devil's claw is safe or what the side effects might be.

Special precautions & warnings:

Pregnancy: Devil's claw is possibly unsafe when used during pregnancy. It might harm the developing fetus. Avoid use.

Breast-feeding: There isn't enough reliable information to know if devil's claw is safe to use when breast-feeding. Stay on the safe side and avoid use.

Heart and circulation problems: Devil's claw may affect heart rate, heartbeat, and blood pressure. It might harm people with disorders of the heart and circulation. If you have one of these conditions, talk with your healthcare provider before starting devil's claw.

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

Low levels of sodium in the body: Devil's claw might decrease levels of sodium in the body. This might worsen symptoms in people who already have low levels of sodium.

Peptic ulcer disease: Devil's claw might increase the production of stomach acids, which might harm people with stomach ulcers. Avoid using devil's claw.

Are there interactions with medications?

Be cautious with this combination.
Medications changed by the liver (Cytochrome P450 2C19 (CYP2C19) substrates)
Some medications are changed and broken down by the liver. Devil's claw might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates)
Some medications are changed and broken down by the liver. Devil's claw might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)
Some medications are changed and broken down by the liver. Devil's claw might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Warfarin (Coumadin)
Warfarin is used to slow blood clotting. Devil's claw might increase its effects and the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin might need to be changed.
Be watchful with this combination.
Medications moved by pumps in cells (P-glycoprotein Substrates)
Some medications are moved in and out of cells by pumps. Devil's claw might change how these pumps work and change how much medication stays in the body. In some cases, this might change the effects and side effects of a medication.
Medications that decrease stomach acid (H2-blockers)
H2-blockers are used to decrease stomach acid. Devil's claw can increase stomach acid. Taking Devil's claw might decrease the effects of H2-blockers.

Some common H2-blockers include cimetidine (Tagamet), ranitidine (Zantac), and famotidine (Pepcid).
Medications that decrease stomach acid (Proton pump inhibitors)
Proton pump inhibitors are used to decrease stomach acid. Devil's claw can increase stomach acid. Taking devil's claw might decrease the effects of proton pump inhibitors.

Some common proton pump inhibitors include omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium).

Are there interactions with herbs and supplements?

There are no known interactions with herbs and supplements.

Are there interactions with foods?

There are no known interactions with foods.

How is it typically used?

Devil's claw has most often been used by adults in doses of 108-2400 mg daily for 8-12 weeks. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Other names

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.


To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.


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Last reviewed - 06/12/2023