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Composition:
Devil's Claw root tincture (f) (Harpagophytum procumbens)
Alcohol content = 65% v/v
Dosage:
Adults: take 10 drops in a small amount of water, 3 times daily, 15 minutes
before meals. Salivate before swallowing.
Historical overview:
Devils Claw gets its name from the "hooks" that cover the fruits skin,
allowing the species to spread. Traditional African and European medicines
use devils claw for its anti-inflammatory and analgesic properties as well
as its tonic activity on the liver and stomach. Traditionally, it is used
for arthritis, gout, muscle pain of all types (myalgia), lumbago, etc. as
well as for loss of appetite, liver disorders and dyspepsia. In African
pharmacopoeia, devils claw is used for urinary and menstrual problems.
Actions and pharmacology:
Devils Claw active principles are iridoids in the form of glycosides (harpagoside,
harpagide, procumbine) or aglycone (harpagegine), as well as flavonoids (kaempferol,
apigenine). The anti-inflammatory activity of Devils Claw and its active
components are controversial. A study published in 1992 evaluated the effect
of devils claw on the production of eicosanoids (inflammation vectors, just
like prostaglandin) during coagulation.(1) The results failed to prove the
expected effect (that of non-steroidal anti-inflammatory agents) on the
metabolism of arachidonic acid.
However, a more recent study evaluating the production of these eicosanoids
found a very clear anti-inflammatory effect. It has been demonstrated that
Devils Claw extract (particularly harpagosides) inhibits the synthesis of
tromboxanes and leukotrienes.(2)
It seems that devils claw extract also has cardiac effects, which could
limit its use in patients on heart medications. This effect has only been
demonstrated in vitro and its actual relevance in humans has never been
demonstrated.(3) Some authors also mention an hypoglycemic effect but no
clinical data supports this affirmation.
The German Commission E acknowledges its benefits in cases of: loss of
appetite, dyspepsia, supportive therapy of degenerative disorders of the
locomotor system.
Scientific studies:
Several well-designed clinical studies demonstrated the efficacy of Devils
Claw in inflammatory disorders. A French double-blind randomized study
compared a devils claw preparation and an anti-inflammatory agent (diacerhein)
in 122 patients with hip and knee osteoarthritis over a period of 4 months.
The Devils Claw extract proved as effective as the anti-inflammatory agent
but had a much better tolerance and was safer.(4) A German 4-week study
conducted on 197 patients with chronic back pain demonstrated that Devils
Claw extract relieves and reduces irritation. Only a few minor and transient
gastro-intestinal side effects were reported.(5)
Precautions, contraindications and interactions
Contraindication:
Known allergy to devils claw.
The only side effects reported, mainly gastric discomforts, are minor and
transient. In one study, a patient reported a headache with tinnitus.
Devils Claw is in contraindicated during pregnancy because of a possible
oxytoxic effect. It is not recommended during breastfeeding.
A theoretical interaction with heart drugs is possible.(3) A case of purpura
(small spontaneous bruises) has been reported during concomitant use with
Coumadin®.(6)
The gastric stimulation noted in traditional African pharmacopoeia could be
bothersome for someone with gastric problems such as ulcers.
References:
1-Moussard C, Alber D, Toubin MM et al. A drug used in traditional medicine,
Harpagophytum procumbens: no evidence for NSAID-like effect on whole blood
eicosanoid production in humans. Prostaglandins Leukot Essential Fatty Acids
1992 Aug;46(4):283-6
2-Loew D, Mollerfeld J, Schrodter A et al. Investigations on the
pharmacokinetic properties of Harpagophytum extracts and their effects on
eicosanoid biosynthesis in vitro and ex vivo. Clin Pharmacol Ther 2001
May;69(5):356-64
3-Occhiuto F et al. A drug used in traditional medicine : Harpagophytum
procumbens DC. IV. Effects on some isolated muscle preparations. J
Ethnopharmacol 1985;13:201-8.
4-Chantre P, Cappelaere A, Leblan D et al. Efficacy and tolerance of
Harpagophytum procumbens versus diacerhein in the treatment of
osteoarthritis. Phytomedicine 1999 Jun;7(3):177-83
5-Chrubasik S, Junck H, Breitschwerdt H et al. Effectiveness of
Harpagophytum extract WS 1531 in the treatment of exacerbation of low back
pain: a randomized, placebo-controlled, double-blind study. Eur J
Anaesthesiol 1999 Feb;16(2):118-29
6-Shaw D, et al. Traditional remedies and food supplements: a 5-year
toxicological study (1991-1995). Drug Safety 1997;17:342-56.
7-The Complete German Commission E Monographs, Therapeutic Guide to Herbal
Medicines. Blumenthal M et al. 1998. American Botanical Council, 6200 Manor
Rd, Austin, Texas, 78723
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Ayurvedic & Herbal Health Medicine
