Usnea - Usnea spp.
Lichens or Lichen family
Plant name: Usnea spp.
Family: Usneaceae
Common names: Old man's beard
Many different species of Usnea are used as medicine, including U. hirta, U.
barbata, U. florida, U. longissima, U. dasypoga, U. bayle and U. lobata.
It has a recorded history of therapeutic use dating back to ancient China (where it
was called Sun-lo and used for cooling an overheated system and as treatment for
surface infections) and it was mentioned in the Formulary of Al-kindi ca. 850 AD.
Botany
Usnea is a lichen (part fungus, part algae) which lives
throughout the northern temperate zones, especially the sub-arctic and coastal
rainforest areas. Usnea has a preference for old growth trees and its habitat is
being steadily eroded by modern logging practices. Usnea should only be bought
from certified wildcrafters who understand the ecological cycles and will not
over harvest. Usnea also has the tendency to accumulate heavy metals from the
air so caution is required when harvesting to ensure that there is sufficient
distance from any significant sources of pollution. The plant has a greyish
green color and grows as a bushy mat from a few inches to two or three feet
long, hanging off the trunks and branches. It feels dry and coarse. Some species
have an inner core of white material which may be exposed by gently pulling on
either end of a strand. The outer coating will tear apart to reveal the tough
inner cord. It is believed to provide tensile strength to the strand and may be
a polysaccharide food store. These white-cored species are considered to offer
the most valuable medicinal effect. When buying Usnea you should look for this
white inner core.
Constituents and actions
Because of their long tradition of use as antimicrobial agents by indigenous peoples,
lichens attracted attention early on in the search for antibiotics. By 1944 it was found
that as many as half the lichens studied contained lichen acids which exhibited variable
antibiotic activity. They are particularly active against gram positive bacteria such
as streptococcus, staphylococcus and mycobacteria and are generally not effective
against gram negative bacteria such as salmonella and E. Coli.
Medicinal Use of some species of Usnea
Usnea
hirta: usnic, thamnolic & usnaric acids, antibiotic
Usnea barbata: barbatolic, usnic, lobaric, tartaric acids, used
homeopathically against headaches and sunstroke
Usnea florida: usnic, stictinic & lobaric acids, antibiotic
and anti-tubercular
Usnea longissima: usnic & evernic acids, expectorant
Usnic acid and its derivatives appear to be the main active constituents
in Usnea spp. It is believed to work against gram positive bacteria by disrupting
cell membrane functions and so preventing ATP formation and oxidative phosphorylation.
Human cells are less permeable to usnic acid and so are not adversely affected.
Usnic acid is only poorly water-soluble so tinctures with about 70% ethyl alcohol
will allow a faster action while simple decoctions are suitable for long term use.
Unidentified constituents in Usnea spp. have also been suggested as offering an
immuno-modulating effect upon the whole leucocyte protection system but this has not
yet been clincally evaluated.
Usnic acid had, in an in vitro experiment, completely inhibited the growth of human
tuberculosis bacillus in dilutions as low as 1 : 50,000 and weakened their growth at
dilutions of only 1 : 200,000. It also inhibited the growth of streptococcus,
Staphylococcus and Pneumococcus at a dilution of 1 : 20,000.
Clinical applications (compiled from discussions with clinical herbalists,
based on empirical evidence)
Antifungal - effective against tinea infections such as ringworm, athletes foot
and also against Candida albicans.
Antiparasitic- effective against Trichomonas and Chlamydia in vaginal infections.
Antibacterial - effective against gram positive bacteria in local or systemic infections
Immune regulator & supporter - boosts the immune system in cases such as
acute and chronic lung infections (pleurisy, TB and pneumonia, colds and flus and any
other time of poor immune function.
Dosage and pharmacy
Traditional uses of Usnea include dusting the powdered herb directly onto open or
infected wounds, making strong decoctions, and tincturing the herb in alcohol to optimize
the immune enhancing effect. It is also successfully employed in a salve where fat is used
as the solvent for lichen acids.
Tincture 1 : 3, 70% alcohol standard adult dose is 3 mL three times daily or more in acute cases.
Contraindications
Caution should be used if applying the herb directly to the skin because an allergic
contact dermatitis may occur. In this event, try using the herb internally instead. There are
no reported side effects of using the tincture or decoction. Many herbalists consider it a safe
herb to use in auto-immune conditions, where the immune system is over active and attacks
selected tissues of thebody, but I would advise caution and regular monitoring
of blood components and immune fractions.
Part used: Whole lichen.
Taste/smell: Astringent, bitter.
Tendencies: Drying, cooling.
Dosage: 1:5 dry strength liquid extract: 20-60 drops1-4 times per day.
Mental picture and specific indications: Usnea is indicated for
infectious conditions with fever.
Use: (a) Antibacterial, (b) Antifungal, (c) Antispasmodic, (d) Antipyretic, (e) Analgesic.
Used in respiratory, urinary and fungal infections.
Category: Cool herbs that transform hot phlegm
Properties: Bitter sweet neutral
Western Functions: Antibiotic, antiseptic,
anti-fungal.
Energetic Functions:
- Opens the chest
- Removes damp heat and transforms phlegm
- Stops bleeding
- Invigorates blood
- Clears heat and toxins
- Clears deficiency heat
Habitat: Old growth trees in cool areas
Caution: Not in pregnancy. May cause contact
dermatitis in topical use, discontinue if rash develops. If used in autoimmune
conditions, monitor immune status carefully.
Preparation: Tincture (1:3-5. 50% alcohol) or
decoct
Dosage: 10 grams in combination, or powdered in a
capsule. Tincture: 3-4 ml 3 times per day. For tuberculosis, tincture, 2-7
droppers 3 times per day for 6 months.
Research:
- Anti bacterial against TB, Pneumococcus, Streptococcus
hemolyticus, Corynebacterium diptheriae.
- Selective for gram positive bacteria.
- Antidotal against toxins from tetanus and diptheria.
- Anti protazoan against Trichomonas vaginalis.
- Carcinostatic in rats.
- Vasodialator. Also relaxes muscles of the uterus, bronchi,
and intestines.
Notes:
In Native American traditions Usnea represents the north
and maintains the ?lungs? of planet earth. In those traditions Usnea has a
sacred primeval relationship with the trees, helping to protect them against
infections.
Homeopathic for headache and sunstroke.
Usnea is not actually a plant but a lichen, which is part
algae and part fungus.
Identified as the lichen is pulled apart to reveal a soft
threadlike ?core?. Usnea is always round.
Usnea was historically used as a bitter tonic.
Used as medicine in Ancient Egypt, Rome, Greece, and China
since before the time of Christ.
Outer portion is anti bacterial. Inner portion is has
polysaccharides and may be immune boosting.
Kills microbes by disrupting cellular metabolism
(preventing ATP formation) rather than destroying the cell structure. It is
estimated that 50% of lichens have antibiotic properties.
Use of Usnea was documented in ?The Formulary of Al-kindi?,
A.D. 850
Usnea is becoming rare and should only be picked in
genuine need. Only take what you need! Take it from downed branches if possible.
Usnea often grows on old-growth trees, it is imperative to not over harvest.
Avoid gathering Usnea from heavily polluted areas, as it can absorb heavy metals
from the air.
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