Leonotis leonurus / Wild dagga

De bladeren en bloemen van de Leonotis leonurus werden al door de Hottentotten van zuidelijk Afrika gerookt vanwege hun euforische werking. De plant groeit vooral in het zuiden en zuidoosten van het Afrikaans continent.

De voornaamste actieve alkaloïde is leonurine. In de traditionele geneeskunde van Afrika is Leonotis gebruikt als onderdeel van allerlei behandelingen. Ook werd het toegepast bij slangenbeten en als talisman om slangen te weg te houden.

Leonotis leonurus or wild dagga (Lion’s Tail), is a member of the mint family, is a perennial shrub native to southern Africa. The flowers are a red-orange color, grow in spikes, and are a favorite of many gardeners because of their beauty. The spikes become clustered inflorescences of interrupted flowers with five two-lipped petals, all joined. Wild dagga’s leaves are opposite, simple, and petiolate (leafstalk), narrowly oblong and linear, and taper at the base. Mildly fragrant, the leaves are densely hairy and grow to about 100 millimeters long and 20 millimeters wide. The shrub itself can grow up to 5 meters high (plants.usda.gov n.d.).

L. leonurus favors warm, dry climates and is drought-tolerant, though it may be grown in almost any temperate environment including shrublands, grasslands, and swamplands. Wild dagga grows in California, Mexico, and the Caribbean, and has become naturalized in Western Australia and New South Wales in Australia. While it can grow in the spring and summer months in temperate climes if well protected and in full sun, it does not endure frost well and may not survive winter unless brought indoors. Wild dagga is a favorite of butterflies, bees, and hummingbirds (Grubber 1991).

Wild dagga propagates via seeds that, in temperate climates, must be sown indoors before the last frost or outdoors after the last frost. To collect seeds from the plant, allow the seedheads to dry before collection. If properly cleaned, the seeds can be successfully stored. In warmer climates, the shrub can grow in the wild (Grubber 1991).

TRADITIONAL USES: Wild dagga is purported to have mildly hallucinogenic effects when either its buds or leaves are dried and smoked. Some cultures have been known to smoke it with cannabis or as a marijuana substitute. As always; we do not advocate this use of the plant in any particular way, and all information herein is provided for historical and educational purposes only.

In some internet reports, there is an urban legend that in Africa, the Hottentot tribe and the Bushmen are known to smoke the buds and leaves of the wild dagga plant as inebriants, either alone or mixed with tobacco. Since the Hottentot didn’t have tobacco, I find this story a bit difficult to believe. L. leonurus is used for recreational purposes, and the Nama tribespeople chew quids of powdered leaves to produced psychoactive effects. Similarly, in Mexico where wild dagga is known as flor de mundo (“flower of the world”) and mota (a colloquial name for marijuana), the plant is used as a Cannabis substitute (Schuldes 1995 cited in Ratsch 1998, 564).

TRADITIONAL PREPARATION: The resin from L. leonurus flowers and leaves may be rubbed off and smoked alone or with other herbs. Likewise, the flowers and leaves themselves may be dried and smoked, or steeped as tea. Wild dagga roots, in addition to the flowers and leaves, may be used to create an extract for medicinal purposes. The Hottentots of South Africa prepare the plant for use as a Cannabis or tobacco substitute by picking shoots and flower buds, drying them, and smoking them or scraping the resin from the leaves and smoking it with tobacco (Ratsch 1998, 564).

MEDICINAL USES: In South Africa, the leaves and roots of L. leonurus are used as a remedy for snake bite and to alleviate the pain of other bites and stings. The decoction of dried leaf or root is used as an external wash to treat itchy skin and eczema. Internally, the tea of the dried leaves is taken to treat headache, bronchitis, high blood pressure and the common cold. Leaf infusions have been used to treat asthma and viral hepatitis.

The extract of wild dagga has antispasmodic effects, and is an antiacetylcholine and antihistamine. Wild dagga can be used to treat irregular or painful menstruation and to improve circulation. In one experimental study, which was undertaken to investigate the anti-nociceptive, anti-inflammatory, and anti-diabetic properties of the leaf extract, it was found that the plant possesses properties that help manage or control pain, arthritis, and other inflammatory conditions, as well as adult-onset type-2 diabetes mellitus. This study gives pharmacological credence to South African folkloric uses of the plant (University of KwaZulu-Natal 2005).

TRADITIONAL EFFECTS: Wild dagga is reported to have hallucinogenic or cannabis-like effects, though these effects alone are mild and the plant is thus mixed with other plants that potentiate the effects such as B. caapi or L. sibiricus (Siberian motherwort). Few chemical studies have been done on wild dagga, though caution in using the plant as an inebriant is recommended as it is rumored to be mildly addictive.

REFERENCES

• • Argueta Villamar, Arturo, Leticia M. Cano Asseleih, and Maria Elena Rodarte, eds. 1994. Atlas de las plantas de la medicina tradicional mexicana. 3 vols. Mexico City: INI.

  • Grubber, Hudson. 1991. Growing the hallucinogens. Berkley, Calif.: 20th Century Alchemist.

  • Antinociceptive, antiinflammatory and antidiabetic effects of Leonotis leonurus (L.) R. BR. [Lamiaceae] leaf aqueous extract in mice and rats. Department of Pharmacology, Faculty of Health Sciences, University of KwaZulu-Natal, Durban, South Africa, 27(4): 257-64, 2005.

  • Plants Profile for Leonotis leonurus. plants.usda.gov. http://plants.usda.gov/java/profile?symbol=LELE3

  • Ratsch, Christian., The Encyclopedia of Psychoactive Plants: Ethnopharmacology and its Applications. Rochester: Park Street Press, 1998.

  • Schuldes, Bert Marco. 1995. Psychoaktive Pflanzen. 2nd ed. Der Grune Zweig 164. Lohrbach: Werner Pieper’s MedienXperiment; Solothurn: Nachtschatten Verlag.

J Ethnopharmacol. 2015 Nov 4;174:520-39. doi: 10.1016/j.jep.2015.08.013. Epub 2015 Aug 18."Wild cannabis": A review of the traditional use and phytochemistry of Leonotis leonurus.Nsuala BN1, Enslin G2, Viljoen A3.

ETHNOPHARMACOLOGICAL RELEVANCE:

Leonotis leonurus, locally commonly known as "wilde dagga" (=wild cannabis), is traditionally used as a decoction, both topically and orally, in the treatment of a wide variety of conditions such as haemorrhoids, eczema, skin rashes, boils, itching, muscular cramps, headache, epilepsy, chest infections, constipation, spider and snake bites. The dried leaves and flowers are also smoked to relieve epilepsy. The leaves and flowers are reported to produce a mild euphoric effect when smoked and have been said to have a similar, although less potent, psychoactive effect to cannabis.

AIM OF THE REVIEW:

To amalgamate the botanical aspects, ethnopharmacology, phytochemistry, biological activity, toxicity and commercial aspects of the scientific literature available on L. leonurus.

METHODS:

An extensive review of the literature from 1900 to 2015 was carried out. Electronic databases including Scopus, SciFinder, Pubmed, Google Scholar and Google were used as data sources. All abstracts, full-text articles and books written in English were considered.

RESULTS:

The phytochemistry of particularly the non-volatile constituents of L. leonurus has been comprehensively investigated due to interest generated as a result of the wide variety of biological effects reported for this plant. More than 50 compounds have been isolated and characterised. L. leonurus contains mainly terpenoids, particularly labdane diterpenes, the major diterpene reported is marrubiin. Various other compounds have been reported by some authors to have been isolated from the plant, including, in the popular literature only, the mildly psychoactive alkaloid, leonurine. Leonurine has however, never been reported by any scientific analysis of the extracts of L. leonurus.

CONCLUSION:

Despite the publication of various papers on L. leonurus, there is still, however, the need for definitive research and clarification of other compounds, including alkaloids and essential oils from L. leonurus, as well as from other plant parts, such as the roots which are extensively used in traditional medicine. The traditional use by smoking also requires further investigation as to how the chemistry and activity are affected by this form of administration. Research has proven the psychoactive effects of the crude extract of L. leonurus, but confirmation of the presence of psychoactive compounds, as well as isolation and characterization, is still required. Deliberate adulteration of L. leonurus with synthetic cannabinoids has been reported recently, in an attempt to facilitate the marketing of these illegal substances, highlighting the necessity for refinement of appropriate quality control processes to ensure safety and quality. Much work is therefore still required on the aspect of quality control to ensure safety, quality and efficacy of the product supplied to patients, as this plant is widely used in South Africa as a traditional medicine. Commercially available plant sources provide a viable option for phytochemical research, particularly with regard to the appropriate validation of the plant material (taxonomy) in order to identify and delimit closely related species such as L. leonurus and L. nepetifolia which are very similar in habit.