Historical Note Damiana is a wild deciduous shrub found in the arid and semi-arid regions of South America, Mexico, United States and West Indies. It is believed that Mayan Indians used damiana to prevent giddiness, falling and loss of balance, and as an aphrodisiac. It has also been used during childbirth, and to treat colic, stop bed wetting and bring on suppressed menses. Today its leaves are used for flavouring in food and beverages, and infusions and other preparations are used for a variety of medicinal purposes. Common Name Damiana Other Names Herba de la pastora, Mexican damiana, miziboc, old woman’s broom, shepherd’s herb, stag’s herb Botanical Name / Family Turnera diffusa, Damiana aphrodisiaca, Turnera aphrodisiaca (family Turneraceae) Plant Parts Used Dried leaves and stems Chemical Components Sesquiterpenes, alkaloids, essential oils containing caryophyllene, delta-cadinene, beta-elemeneand 1-8 cineol and other lesser constituents, tetraphylin B (a cyanogenic glycoside, 0.26%), resin, tannins, gum, mucilage, starch, a bitter element and possibly caffeine. Damiana also contains a flavone and at least five flavonoids including arbutin. Main Actions The pharmacological actions of damiana have Read more […]

Dandelion: Uses. Dosage. Interactions. Pregnancy Use. Practice Points

Clinical Use The therapeutic effectiveness of dandelion has not been significantly investigated under clinical trial conditions, so evidence is derived from traditional, in vitro and animal studies. DIURETIC Dandelion has a long history of use as a diuretic in well-established systems of traditional medicines; however, the scientific and clinical evidence to support this use is limited to animal studies. The high potassium content of dandelion is considered to be partly responsible for any diuretic activity. A double-blind randomised study of 57 women with recurrent cystitis found that a commercial preparation known as Uva-E (a combination of Arctostaphylos leaves and dandelion root) significantly reduced the frequency of recurrence of cystitis compared with placebo. At the end of 12 months, none of the patients taking Uva-E had had a recurrence of cystitis, compared with 23% recurrence in the control group (P < 0.05). The role of dandelion in achieving this result is unknown; however, the researchers suggested that its diuretic effect was likely to have contributed to the positive results. LIVER TONIC Dandelion has a long history of use as a liver tonic; however, the scientific and clinical evidence to support Read more […]

Dandelion: Background. Actions

Historical Note Dandelion grows throughout the world as a weed and has a long history of medicinal and culinary use. Dandelion leaves are added to salads, providing a good source of minerals, and the roasted root is used as a coffee substitute. Dandelion leaves are traditionally used as a diuretic, and the root is used as a liver tonic. Other Names Blowball, cankerwort, common dandelion, lion’s tooth, priest’s crown, puff ball, swine snout, taraxacum, wild endive, white endive Botanical Name / Family Taraxacum officinale; synonyms: Leontodon taraxacum, Taraxacum vulgare (family Compositae [Asteraceae]) Plant Parts Used Leaf and root Chemical Components Dandelion leaf and root contain slightly different constituents. Overall, dandelion is a rich source of minerals, particularly potassium, as well as iron, magnesium, zinc, potassium, manganese, copper, choline, selenium, calcium, boron and silicon, and a rich source of vitamins A, C, D and B complex (US Department of Agriculture 2003). The relatively high protein, fibre and linoleic acid content of dandelion leaves has led to suggestions that dandelion is a nutritious and underutilised food source. Dandelion’s constituents also include triterpenes, flavonoid Read more […]

Devil’s claw: Dosage. Interactions. Pregnancy Use. Practice Points

Dosage Range MUSCULOSKELETAL CONDITIONS • Dried root or equivalent aqueous or hydroalcoholic extracts: 2-6 g daily for painful arthritis; 4.5-9 g daily for lower back pain. • Liquid extract (1:2): 6-12 mL/day. • Tincture (1:5): 2-4 mL three times daily. It is suggested that devil’s claw extracts with at least 50 mg harpagoside in the daily dosage should be recommended for the treatment of pain. DIGESTIVE CONDITIONS (e.g. DYSPEPSIA) • Dosages equivalent to 1.5 g/day dried herb are used. It is suggested that devil’s claw preparations be administered between meals, when gastric activity is reduced. Toxicity The acute LD50 of devil’s claw was more than 13.5 g/kg according to one study. Adverse Reactions Diarrhoea was reported in one clinical study. Significant Interactions Devil’s claw has been found to moderately inhibit cytochrome P450 enzymes in vitro, however, the clinical relevance of this is yet to be determined. WARFARIN Rare case reports suggest that devil’s claw may potentiate the effects of warfarin, requiring caution and possible dose adjustments; however, clinical testing is required to confirm this — use caution in patients receiving warfarin. ANTIARRYTHMIC DRUGS Theoretical Read more […]

Devil’s claw: Uses

Clinical Use ARTHRITIS Overall, current evidence from clinical trials suggest that devil’s claw may be a useful treatment for arthritis; however, it is suggested, as with many herbal medicines, that evidence of effectiveness is not transferrable from product to product and that the evidence is more robust for products that contain at least 50 mg of harpagoside in the daily dosage. An observational study of 6 months’ use of 3-9 g/day of an aqueous extract of devil’s claw root reported significant benefit in 42-85% of the 630 people suffering from various arthritic complaints. In a 12-week uncontrolled multicentre study of 75 patients with arthrosis of the hip or knee, a strong reduction in pain and the symptoms of osteoarthritis were observed in patients taking 2400 mg of devil’s claw extract daily, corresponding to 50 mg harpagoside. Similar results were reported in a 2-month observational study of 227 people with osteoarthritic knee and hip pain and non-specific low back pain and a double-blind study of 89 subjects with rheumatic complaints using powdered devil’s claw root (2 g/day) for 2 months, which also provided significant pain relief, whereas another double-blind study of 100 people reported benefit after Read more […]

Devil’s claw: Background. Actions

Historical Note The botanical name Harpagophytum means ‘hook plant’ in Greek, after the hook-covered fruits of the plant. Devil’s claw is native to southern Africa and has been used traditionally as a bitter tonic for digestive disturbances, febrile illnesses, allergic reactions and to relieve pain. It has been used in Europe for the treatment of rheumatic conditions for over 50 years, and was first cited in the literature by Zorn at the University of Jena, Germany, who described his observations on the antiphlogistic and anti-arthritic effects after administration of oral aqueous extracts prepared from the secondary roots of Harpagophytum procumbens in patients suffering from arthritides. Common Names Devil’s claw root, grapple plant, harpagophytum, wood spider Botanical Name / Family Harpagophytum procumbens (family Pedaliaceae) Plant Part Used Dried tuber/root Chemical Components The major active constituent is considered to be the bitter iridoid glucoside, harpagoside, which should constitute not less than 1.2% of the dried herb. Other iridoid glycosides include harpagide and procumbide. About 50% of the herb consists of sugars. There are also triterpenes, phytosterols, plant phenolic acids, flavonol glycosides Read more […]

Echinacea: Adverse Reactions. Interactions. Pregnancy Use. Practice Points

Dosage Range GENERAL GUIDE • Dried herb: 3 g/day of either Echinacea angustifolia or Echinacea purpurea. • Liquid extract (1:2): 3-6 mL/day of either Echinacea angustifolia or Echinacea purpurea. This dose may be increased to 10-20 mL/day in acute conditions. Treatment is usually started at the first sign of URTI and continued for 7-14 days. SPECIFIC GUIDE • Echinacea angustifolia dried root: 1-3 g/day. • Echinacea purpurea dried root: 1.5-4.5 g/day. • Echinacea purpurea dried aerial parts: 2.5-6.0 g/day. • Echinacea purpurea expressed juice of fresh plant: 6-9 mL/day. • Echinacea pallida ethanolic extract of root: 2-4 mL/day. Although controversy still exists over which part of the plant and which particular plant has the strongest pharmacological activity, it appears that the cold-pressed juice of Echinacea purpurea is the most studied preparation for URTIs. Adverse Reactions Oral dose forms and topical preparations tend to be well tolerated, although allergic reactions are possible in rare cases (mainly to the aerial parts, in contact dermatitis). One study using Echinacea purpurea in children found that rash occurred in 7.1% of children using echinacea compared with 2.7% with Read more […]

Echinacea: Uses

Clinical Use Clinical trials using echinacea have used various preparations, such as topical applications, homeopathic preparations, injectable forms and oral dose forms, characteristics that should be noted when reviewing the data available. Overall, the majority of clinical studies performed in Europe have involved a commercial product known as Echinacin (Madaus, Germany), which contains the fresh-pressed leaf juice of Echinacea purpurea stabilised in ethanol. UPPER RESPIRATORY TRACT INFECTIONS Overall, clinical studies support the use of echinacea in URTIs, such as bacterial sinusitis, common cold, influenza-like viral infections and streptococcal throat. Evidence is strongest for use of echinacea in adults as an acute treatment; however, results in children have been disappointing. A 1999 review of 13 clinical trials consisting of 9 treatment studies and 4 prevention studies concluded that 8 of 9 treatment trials produced positive results whereas 3 of 4 prevention trials suggested modest effects. In other words, current evidence is stronger for supporting the use of echinacea as acute treatment in URTIs than as prophylactic treatment. In 2000, a Cochrane review was published that had assessed the evidence Read more […]

Echinacea: Background. Actions

Historical Note Echinacea was first used by Native American Sioux Indians centuries ago as a treatment for snakebite, colic, infection and external wounds, among other things. It was introduced into standard medical practice in the USA during the 1 800s as a popular anti-infective medication, which was prescribed by eclectic and traditional doctors until the 20th century. Remaining on the national list of official plant drugs in the USA until the 1940s, it was produced by pharmaceutical companies during this period. With the arrival of antibiotics, echinacea fell out of favour and was no longer considered a ‘real’ medicine for infection. Its use has re-emerged, probably because we are now in a better position to understand the limitations of antibiotic therapy and because there is growing public interest in self-care. The dozens of clinical trials conducted overseas have also played a role in its renaissance. Common Name Echinacea Other Names Echinacea angustifolia — American coneflower, black sampson, black susans, coneflower, echinaceawurzel, Indian head, kansas snakeroot, purple coneflower, purpursonnenhutkraut, racine d’echinacea, Rudbeckia angustifolia L, scurvy root, snakeroot Echinacea purpurea — Read more […]

Fenugreek: Interactions. Contraindications. Pregnancy Use. Practice Points. FAQ

Toxicity Safety studies indicate that fenugreek is extremely safe. When consumed as 20% of the diet, it did not produce toxic effects in animal tests. Adverse Reactions One clinical study found that a dose of 50 g taken twice daily produced mild gastrointestinal symptoms, such as diarrhea and flatulence, which subsided after 3-4 days. Allergic reactions have been reported, but are rare. Significant Interactions Where controlled studies are not available, interactions are speculative and based on evidence of pharmacological activity and case reports. HYPOGLYCAEMIC AGENTS Additive effects are theoretically possible in diabetes — monitor concomitant use and monitor serum glucose levels closely — potentially beneficial interaction. IRON Frequent use of fenugreek can inhibit iron absorption — separate doses by 2 hours. WARFARIN Although there is a theoretical concern that concomitant use could increase bleeding risk due to the herb’s coumarin content, this is unlikely. A placebo-controlled study found that fenugreek does not affect platelet aggregation, fibrinolytic activity or fibrinogen. Contraindications and Precautions Fenugreek is contraindicated in people with allergy to the herb, which has been Read more […]