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Arctostaphylos uva-ursi (L.) Spreng.
(Ericaceae)
Synonyms
Arbutus uva-ursi L., Arctostaphylos media Greene, Arctostaphylos officinalis
Wimm., Arctostaphylos procumbens Patzke, Mairania uva-ursi Desv., Uva-ursi buxifolia
S.F. Gray, Uva-ursi procumbens Moench.
Local names
Achelblätter, Achelkraut, arberry, arctostaphylos, Bärenkraut, Bärentraube,
Bärentraubenblätter, bearberry, bear’s grape, Beredruif, berry
leaves, brockberry, busserole, coralillo, crowberry, dogberry, enab edhdhib,
feuille de busserole, feuille de raisin d’ours, folia artostaphyli, folia
garjubae, folia uvae-ursi, folia vaccinii ursi, foxberry, gayuba, herba garjubae,
hog cranberry, hojas de ayuba, kinnikinnick, leesikas, lisc maçznicy,
mealyberry, medveszölölevel, Moosbeerenblätter, mountain box,
ptarmigan berry, raisin d’ours, red bearberry, sagochomi, Sandblätter,
Steinbeerenblätter, upland cranberry, uva ursi, uvaursina, uwaurushi, Wolfsbeerenblätter
Description
Procumbent evergreen shrub with trailing stems bearing short ascending branches;
branches bear leaves that are ovate, ovate-spatulate to spatulate. Flowers bell-shaped,
pinkish-white, hypogynous and borne in small clusters at ends of branches; each
flower consists of a calyx of 5 reddish sepals, a reddish-white urceolate corolla,
gamopetalous but divided at the margin into 5 short reflexed segments, 10 short
stamens with 2-lobed anthers, and syncarpous pistil of 5 carpels. Style portion
of the pistil simple, longer than the stamens and ends in a knob-like stigma
Plant material used
dried leaves
Chemical assays
Contains not less than 7% hydroquinone derivatives calculated as anhydrous arbutin,
according to The Japanese pharmacopoeia. Contains not less than 8%
Major chemical constituents
The major constituent is arbutin (5–15%). Related hydroquinone derivatives
present include hydroquinone and methylarbutin (up to 4%). Gallic acid is the
major phenolic carboxylic acid present, together with galloyl arbutin and up
to 20% of gallotannins, flavonoids and triterpenes, mainly ursolic acid and
uvaol
Medicinal uses
Uses supported by clinical data
None.
Uses described in pharmacopoeias and well
established documents
Internally, as a mild urinary antiseptic for moderate inflammatory conditions
of the urinary tract and bladder, such as cystitis, urethritis and dysuria.
Uses described in traditional medicine
As a diuretic, to stimulate uterine contractions, and to treat diabetes, poor
eyesight, renal or urinary calculi, rheumatism and venereal disease. Topical
applications have been used for skin depigmentation
Proven pharmacological activity
Animal studies
Antimicrobial, Anti-inflammatory, Antitussive, Skin lightening
Human studies
Antibacterial
Toxicity and overdose
The oral LD50 of hydroquinone ranged from 300 to 1300mg/kg body weight in rodents
and dogs, but was only 42–86mg/kg body weight in cats. Acute exposure
of rats to high doses of hydroquinone (over 1300mg/kg body weight) caused severe
effects on the central nervous system, including hyperexcitability, tremor,
convulsions, coma and death
Contraindications
During pregnancy or lactation, or in children under the age of 12 years. Folium
Uvae Ursi is also contraindicated in patients with kidney disorders.
Warnings
Folium Uvae Ursi should not be used for prolonged periods. Patients with persistent
symptoms of a urinary tract infection should consult a physician. Use of Folium
Uvae Ursi may cause a greenish-brown coloration of the urine that darkens on
exposure to air due to the oxidation of hydroquinone.
Precautions
Drug interactions
Folium Uvae Ursi should not be administered with foods or medicines that acidify
the urine.
Carcinogenesis, mutagenesis, impairment of fertility
Folium Uvae Ursi was not mutagenic in the Salmonella/microsome assay with S.
typhimurium strains TA98 or TA100. Hydroquinone was also not mutagenic in the
Salmonella/microsome assay with S. typhimurium strains TA98, TA100, TA1535 or
TA1537, with or without metabolic activation. Although extracts of the leaves
do not appear to be carcinogenic, there is some evidence that hydroquinone is
carcinogenic. Treatment of F344/N rats with hydroquinone resulted in a marked
increase in tubular cell adenomas of the kidney in males, and an increase in
mononuclear cell leukaemia in females. There was also some evidence of carcinogenic
activity of hydroquinone in female B6C3F1 mice, as shown by an increase in hepatocellular
neoplasms, mainly adenomas. There was no evidence, however, of carcinogenic
activity of an aqueous extract of the leaves in male B6C3F1 mice (treated by
gavage with 50–100mg extract/kg body weight). The sources of human exposure
to hydroquinone (including environmental sources) have bee reviewed, as have
data on its kinetics and metabolism, and its effects in animals and humans.
Arbutin was administered subcutaneously at 25, 100 or 400mg/kg body weight daily
to male rats before mating, and to female rats during pregnancy and lactation.
No effect on reproduction of male and female rats, or the development of the
offspring was observed at doses of up to 100mg/kg body weight. Fetal toxicity
was observed at doses of 400mg/kg body weight.
Pregnancy: teratogenic effects
See Contraindications.
Pregnancy: non-teratogenic effects
See Contraindications.
Nursing mothers
See Contraindications.
Paediatric use
See Contraindications.
Other precautions
No information available on general precautions or precautions concerning drug
interactions; or drug and laboratory test interactions.
Adverse reactions
Internal use of Folium Uvae Ursi may cause nausea and vomiting due to stomach
irritation from the high tannin content. The hydroquinone concentration in topical
preparations is limited to 2% in Nigeria, the United Kingdom and the United
States of America, following reports that preparations containing more than
2% hydroquinone caused exogenous ochronosis in black women in South Africa.
Topical application of preparations containing less than 3% hydroquinone in
different bases caused negligible effects in male volunteers from different
racial groups. However, there are case reports suggesting that skin-lightening
creams containing 2% hydroquinone have produced leukoderma as well as ochronosis.
Hydroquinone (at a concentration of 1% in aqueous solution or 5% in a cream)
has caused erythema and allergic contact dermatitis.
Dosage forms
Crude drug for infusions or cold macerates, extracts and solid forms for oral
administration. Store in a well-closed container, protected from light.
Posology
(Unless otherwise indicated)
Daily dose: 3g crude drug in 150 ml water as an infusion or cold macerate, up
to three or four times daily; 400–850mg hydroquinone derivatives. Other
preparations accordingly calculated as arbutin. Patients should avoid highly
acidic foods, such as acidic fruits or fruit juice, during treatment, and be
advised to drink plenty of fluids.
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