Standardized Devil's Claw [Discontinued] by Nature's Way

POSSIBLY EFFECTIVE

• Back pain. Taking devil's claw orally seems to lessen nonspecific low-back pain. Details: Some clinical research shows that taking aqueous extracts of devil's claw orally can decrease low back pain similarly to rofecoxib (Vioxx) and other non-steroidal anti-inflammatory drugs (NSAIDs). Specific products used in clinical research include Doloteffin (Ardeypharm) 800 mg three times daily for up to 1 year, WS 1531 (Dr. Willmar Schwabe GmbH & Co.) 200-400 mg three times daily for 4 weeks, and LI 174 (Rivoltan, Krewel Meuselbach GmbH) 480 mg twice daily for 4-8 weeks (8608,12477,14118,47112,47116,47117,47155,47169,47170).
• Osteoarthritis. Taking devil's claw orally, alone or in conjunction with nonsteroidal anti-inflammatory drugs (NSAIDs), seems to help decrease osteoarthritis pain. Details: Some clinical research shows that devil's claw is comparable to diacerhein (not available in the US) for improving osteoarthritis pain in the hip and knee after 16 weeks of treatment, and it decreases use of NSAIDs for pain relief. These studies used a specific powdered devil's claw root product (Harpadol, Arkopharma) 2610 mg daily for 4 months (6472,47114). Another specific devil's claw extract (Doloteffin, Ardeypharm) 2400 mg daily in 3 divided doses for 8-12 weeks, providing 60 mg harpagoside daily, has also been used (8608,14332). Some research has also evaluated devil's claw in combination with other ingredients. One clinical study shows that taking a specific combination solution (Rosaxan, medAgil Gesundheitsgesellschaft mbH) containing devil's claw 108 mg, stinging nettle 160 mg, rose hip puree 20 grams, rose hip juice concentrate 4 grams, and vitamin D 200 IU orally daily for 12 weeks improves overall symptoms by an additional 28% and pain scores by an additional 33% when compared with placebo in adults with knee osteoarthritis (96741). Another clinical study shows that a combination of devil's claw 300 mg, turmeric 200 mg, and bromelain 150 mg per capsule (AINAT, Laboratoire de Rhumatologie Appliquee), taken as two capsules three times daily for 2 weeks, or twice daily for 2 months, significantly improves acute and chronic pain in patients with osteoarthritis (91106). Also, a small, open-label clinical study in patients with mild knee osteoarthritis shows that taking a specific combination product (Tregocel, Max Biocare) providing devil's claw 1000 mg, celery seed 1000 mg, Boswellia serrata resin extract 1000 mg, ginger rhizome 330 mg, and curcumin 180 mg daily for 36 weeks reduces pain, improves functional capacity, and increases walking distance when compared with baseline (106078). The validity of the findings from these last two studies is limited by the lack of a comparator group. Additionally, it is unclear if the findings from any of these studies are due to devil's claw, other ingredients, or the combinations.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Atherosclerosis. Although there is interest in using oral devil's claw for atherosclerosis, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Dysmenorrhea. Although there is interest in using oral devil's claw for dysmenorrhea, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Dyspepsia. Although there is interest in using oral devil's claw for dyspepsia, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Fibromyalgia. Although there is interest in using oral devil's claw for fibromyalgia, there is insufficient reliable information about the clinical effects of devil's claw for this condition.
• Gout. Oral devil's claw root extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small, open-label clinical study in patients with gout shows that taking a specific combination product (GoutFighter, Max Biocare) containing devil's claw root extract 300 mg, celery seed extract 600 mg, sour cherry extract 200 mg, and other ingredients twice daily for 45 days reduces pain, joint inflammation, and uric acid levels when compared with baseline (106488). The validity of these findings is limited by the lack of a comparator group. Additionally, it is unclear if these findings are due to devil's claw, other ingredients, or the combination.
• Migraine headache. Although there is interest in using oral devil's claw for migraine headache, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Myalgia. Although there is interest in using oral devil's claw for myalgia, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Parturition. Although there is interest in using oral devil's claw for parturition, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Rheumatoid arthritis (RA). It is unclear if oral devil's claw is beneficial in patients with RA. Details: Preliminary clinical research shows that taking devil's claw root extract orally (Salus-Hause-Floradix) 410 mg three times daily for 6 weeks does not improve any measures of RA symptoms when compared with baseline (8613). The validity of these results is limited by the lack of a comparator group.
• Tendinopathy. Although there is interest in using oral devil's claw for tendinopathy, there is insufficient reliable information about the clinical effects of devil's claw for this purpose.
• Wound healing. Although there is interest in using topical devil's claw for wound healing, there is insufficient reliable information about the clinical effects of devil's claw for this purpose. More evidence is needed to rate devil's claw for these uses.

(Read more about DEVIL'S CLAW)

POSSIBLY SAFE ...when used orally and appropriately. Devil's claw extract has been used with apparent safety in doses of up to 2400 mg daily for up 12 weeks (6472,8608,14332,14418,47112,47114,47116,47117,47155). There is insufficient reliable information available about the safety of devil's claw when used orally long-term or when used topically.

PREGNANCY: POSSIBLY UNSAFE
when used orally. Anecdotal evidence suggests that devil's claw has oxytocic effects in humans. Also, in vitro research shows that moderate to high doses of devil's claw root extract induce contractions of isolated uterine muscle from pregnant and nonpregnant rats (94689); avoid using.

LACTATION:
Insufficient reliable information available; avoid using.

(Read more about DEVIL'S CLAW)

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, devil's claw might increase levels of drugs metabolized by CYP2C19.  Details In vitro research shows that devil's claw might inhibit CYP2C19, although this has not been reported in humans (12479).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, devil's claw might increase levels of drugs metabolized by CYP2C9.  Details In vitro research shows that devil's claw might inhibit CYP2C9, although this has not been reported in humans (12479).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, devil's claw might increase levels of drugs metabolized by CYP3A4.  Details In vitro research shows that devil's claw might inhibit CYP3A4, although this has not been reported in humans (12479).

H2-BLOCKERS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, devil's claw might decrease the effectiveness of H2-blockers.  Details Devil's claw has been reported to increase stomach acid, which might interfere with the effects of H2-blockers (19).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, devil's claw might increase levels of P-glycoprotein substrates.  Details In vitro research shows that devil's claw inhibits P-glycoprotein, which transports many drugs out of cells (17325). This might increase intracellular levels of P-glycoprotein substrates, although it is unclear if this effect would be clinically important (17325).

PROTON PUMP INHIBITORS (PPIs) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, devil's claw might decrease the effectiveness of PPIs.  Details Devil's claw has been reported to increase stomach acid, which might interfere with the effects of PPIs (19).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, Devil's claw might increase the activity of warfarin.  Details In one case report, purpura occurred in a patient taking warfarin and devil's claw concurrently. This might indicate over-anticoagulation (613). It is unclear if this was due to Devil's claw or other contributing factors.

(Read more about DEVIL'S CLAW)

General ...Orally, Devil's claw seems to be generally well tolerated.
Most Common Adverse Effects:
Orally: Allergic skin reactions, diarrhea, dyspepsia.
Serious Adverse Effects (Rare):
Orally: Gastrointestinal bleeding.

Cardiovascular ...In one case report, a healthy patient with normal blood pressure presented with hypertension after taking devil's claw 250 mg twice daily for 2 weeks. It gradually resolved after discontinuation of devil's claw (92017). Some animal research shows that devil's claw might have negative chronotropic, as well as positive and negative inotropic, effects (8609). However, these effects have not been documented in humans.

Dermatologic ...Rarely, allergic skin reactions have been reported in patients taking devil's claw (8608,14418).

Endocrine ...In one case report, a 65-year-old female developed psychomotor agitation, nausea, and distress from euvolemic hyponatremia secondary to inappropriate secretion of antidiuretic hormone (SIADH) within 1 month of starting daily treatment with devil's claw. Within 5 days of discontinuing the product and receiving sodium replacement, the symptoms resolved. Two months later, the patient re-initiated devil's claw and again developed euvolemic hyponatremia (96747).

Gastrointestinal ...Gastrointestinal side effects, including mild gastrointestinal upset, diarrhea, anorexia, acid reflux, or loss of taste, have been reported in some individuals receiving devil's claw, especially at high doses (6472,8608,8613,14332,14418,47112,47116,47144,47169). Gastrointestinal complaints have been reported in 9% to 18% of patients taking a specific devil's claw extract (Doloteffin, Ardeypharm) (8608,47169), while diarrhea was reported in about 8% of patients taking devil's claw (Harpadol, Arkopharma) (6472). Several cases of gastrointestinal bleeding have been reported (104977).

Genitourinary ...Dysmenorrhea was reported in one patient taking a specific devil's claw extract (Doloteffin, Ardeypharm) for 8 weeks (8608).

Neurologic/CNS ...In a trial of devil's claw, one patient withdrew after 4 days of therapy due to a throbbing frontal headache, as well as tinnitus, anorexia, and loss of taste (8613). Rarely, dizziness, somnolence, and insomnia have been reported (47116,47169). It is unclear if these symptoms were caused by devil's claw.

Psychiatric ...Rarely, anxiety has been reported in patients taking devil's claw (8608).

(Read more about DEVIL'S CLAW)