Devil's claw

What is devil's claw?

Devil's claw is a plant whose botanical name Harpagophytum means "hooked plant" in Greek. Devil's claw is native to Africa and takes its name from its fruit, which is covered with hooks that catch on animals, which then disperse the seeds. The roots and tubers of this plant are used to make medicine. Devil's claw is used for hardened arteries (arteriosclerosis), arthritis, gout, muscle pain, back pain, tendonitis, chest pain, digestive problems, heartburn, fever and migraine headaches. It is also used for birth problems, menstrual problems, allergic reactions, loss of appetite and kidney and bladder disorders. Some people apply devil's claw to the skin for injuries and other skin problems.

How effective are devil's claw supplements?

Devil's claw may be effective for the following conditions:

• Reducing the pain of osteoarthritis: taking devil's claw on its own or in conjunction with non-steroidal anti-inflammatory drugs appears to reduce pain associated with osteoarthritis. There is evidence that devil's claw works as well as diacerhein (a slow-acting drug used to treat osteoarthritis) in relieving osteoarthritis pain in the hip and knee as part of a 16-week course of treatment. Some people who use devil's claw seem to be able to reduce the dosage of non-steroidal anti-inflammatory drugs they need to relieve their pain. This evidence comes from a study using a specific devil's claw product containing 2% of the ingredient harpagoside of devil's claw (9.5 mg/capsule) and 3% iridoid glycosides (14.5 mg/capsule). Another specific devil's claw product was used at a dosage of 2,400 mg per day, which corresponds to 60 mg harpagoside.
• Back pain: Taking a devil's claw product appears to relieve lower back pain.

Early research suggests that devil's claw is unlikely to relieve rheumatoid arthritis.

There is not enough scientific data on the effectiveness of devil's claw for stomach problems, loss of appetite, high cholesterol, gout, muscle pain, migraine headaches, skin lesions and other skin conditions to make a conclusive statement. Further research is needed in this area.

How does devil's claw work?

Devil's claw contains chemicals that can relieve inflammation and swelling, as well as the resulting pain.

Are there any safety concerns?

Devil's claw can probably be considered safe for most adults when used in an appropriate dosage for up to a year. The most common side effect is diarrhea. About 8% of subjects who participated in a research study suffered from diarrhea. Other possible side effects include nausea, vomiting, abdominal pain, headaches, ringing in the ears, loss of appetite and loss of sense of taste. Devil's claw can also cause allergic reactions, menstrual problems and changes in blood pressure. Not enough is known about the safety of long-term use or application to the skin.

Precautions and warnings

Pregnancy and breastfeeding: Devil's claw is probably not safe during pregnancy and could harm the developing fetus. For this reason, devil's claw should not be taken during pregnancy. To be on the safe side, devil's claw should also be avoided while breastfeeding, as not enough is known about its safety during lactation.

Heart problems, high or low blood pressure: As devil's claw can affect the heart rate, heartbeat and blood pressure, it could be harmful to people with disorders of the heart and cardiovascular system. If you suffer from such a disease, you should discuss the use of devil's claw with your doctor.

Diabetes: Devil's claw can lower blood sugar levels. Using it in combination with medication that lowers blood sugar levels could lead to an excessive drop in blood sugar levels. For this reason, blood sugar levels should be carefully monitored. It may also be necessary to adjust the dosage of diabetes medication.

Gallstones: Devil's claw can increase bile acid production. This can be a problem for people suffering from gallstones. People with gallstones should avoid devil's claw for this reason.

Stomach ulcers: As devil's claw can increase stomach acid production, it could be harmful for people suffering from stomach ulcers. People who suffer from stomach ulcers should avoid devil's claw for this reason.

Does it interact with medication?

You should be careful when combining it with the following medications:

Medications that are broken down via the liver (cytochrome P450 2C19 (CYP2C19) substrates, cytochrome P450 2C9 (CYP2C9) substrates and cytochrome P450 3A4 (CYP3A4) substrates).

Some drugs are broken down via the liver. Devil's claw can slow down the rate at which some drugs are broken down by the liver. Therefore, taking devil's claw with drugs that are broken down by the liver can increase the effects and side effects of these drugs. For this reason, you should discuss the use of devil's claw with your doctor if you are taking medication that is broken down by the liver.

Warfarin

Warfarin is used to slow down blood clotting. Devil's claw can increase the effect of warfarin and thus increase the risk of bleeding and the tendency to bruise. For this reason, the blood should be checked regularly. It is possible that the warfarin dosage may need to be adjusted if you are taking devil's claw.

Care should be taken when combining with the following medications

Drugs that are transported into the cells by pumps (P-glycoprotein substrates)

Some drugs are transported into the cells by pumps. Devil's claw can make these pumps less active and increase the amount of drug absorbed by the body. This can increase the side effects of certain medications.

Drugs that reduce stomach acid (H2 blockers, proton pump inhibitors)

Devil's claw can increase stomach acid production. By increasing stomach acid production, devil's claw may reduce the effectiveness of some medications that reduce stomach acid production.

Are there any interactions with medicinal herbs and supplements?

There are no known interactions with medicinal herbs or supplements.

Are there any interactions with food?

There are no known interactions with food.

Dosages used

The following dosages have been scientifically studied:

• For osteoarthritis: a specific devil's claw product was used at a dosage of 2.6 grams per day. This dose provided 57 mg of harpagoside - one of the active ingredients of devil's claw - and 87 mg of iridoid glycosides - another active ingredient.
• For back pain: A specific devil's claw extract containing 50 to 100 mg of the active ingredient harpagoside was taken daily.

References

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