Kinnikinnick. Kinnikinnick leaves

Kinnikinnick. Kinnikinnick leaves

Kinnikinnick. Kinnikinnick leaves

Specification & Spread

Kinnikinnick leaves — folia uvae ursi
Kinnikinnick— Arctostaphylos uva-ursi (L.) Spreng.
Heath family — Ericaceae
Other names: bear ears, bear grapes, bearberry, tortilla, bearberry, drupe, bearberry. It is a strongly branched low-growing evergreen shrub with prostrate shoots up to 2 m tall.
The leaves are alternate obovate, wedge-shaped at the base, gradually turning into a short petiole, small, slightly shiny, leathery.
The flowers are whitish-pink, resemble bells, are collected in drooping short apical brush. The corolla is a jug-shaped, spinolepedic with a five-toothed limb. There are 10 stamens.
The pestle is with upper five-celled ovary.
The fruit is a coenocarp inedible powdery reddish, with 5 stones.
It blooms in May – June, the fruits ripen in July – August.

Spreading. The forest zone of the European part, Siberia and the Far East of Russia, as well as in the Caucasus and the Carpathians. The main areas of harvesting, where there are productive thickets, – Lithuania, Belarus, Pskov, Novgorod, Vologda, Leningrad and Tver regions of Russia. Recently, thickets have been discovered in new areas: the Krasnoyarsk Territory, the Irkutsk Region and Yakutia. Habitat. Mainly it grows in dry larch and pine forests (pine forests) with a lichen cover (white-hammers), as well as in open sandy places, coastal dunes, rocks, burns and cuttings. Photophilous plant occurs absently, large thickets does not form.


The active ingredient is arbutin fenologlycoside, which is a beta-D-glucopyranoside hydroquinone (8-16%). The leaves are rich in tannins of the hydrolyzable group (from 7.2 to 41.6%). The smaller amount contains methylarbutin, hydroquinone, galloylarbutin, and triterpenoids – ursolic acid (0.4-0.7%), flavonoids, catechins, phenolcarboxylic acids – gallic, ellagic.

In the leaves of bearberry a lot of iodine (2.1-2.7 mcg/kg). Glycoside arbutin under the influence of the enzyme arbutase is hydrolyzed to hydroquinone and glucose.

Qualitative reactions.

A water decoction of the leaves is used: the decoction (1:20) when agitated with an iron crystal of ferrous sulfate gradually forms a dark purple precipitate (arbutin). The decoction of the leaves of kinnikinnick when adding a solution of iron-ammonium alum gives a black and blue coloring (tannins of the hydrolyzable group), and a decoction of leaves of cranberry- black and green colouring (tannins of the condensed group).

Harvesting and storage of raw materials

Harvesting. The harvesting of leaves should be carried out in two terms: in spring – before flowering or at the very beginning of flowering (from late April to mid-June) and in autumn – from the moment of ripening of the fruit to shedding (from late August to mid-October). After flowering, the growth of young shoots begins; leaves collected at this time turn brown when dried and, in addition, contain a small amount of arbutin. When harvesting raw materials leafy shoots (twigs) are cut off with a special knife or chopped off with a hoe. The chopped off branches are harvested, brushed from sand and moss and transported to the place of drying.

Apical shoots (Cormi Uvae ursi) are 20-30 cm long, which are cut with a knife or scissors, are allowed for harvesting, which increases the productivity of collectors. However, in pharmaceutical practice, this type of raw material is practically not found.

Security measures. Breaking branches and pulling out plants with their hands is not allowed. In order to preserve the thickets, it is necessary to alternate the harvesting areas using the same array no more than once every 5 years. It is advisable to create reserves for kinnikinnick.

Drying. It grows in natural conditions: in attics or under a canopy. The raw materials are laid loosely, in a thin layer, periodically tedded. The dried twigs are threshed, picked,  the stems are discarded, the leaves are blackened. The crushed raw materials and mineral admixture are cast on a sieve. The yield of dry raw materials 50% in relation to the newly collected. The artificial drying is allowed at a temperature not higher than 50 °C.

Storage. It is stored in a dry and well-ventilated area.

Whole raw materials

The leaves are small, leathery, dense, brittle, entire, obovate or oblong-obovate, rounded at the apex, sometimes with a small notch, tapered to the base, with a very short petiole . The leaf length is 1-2.2 cm, the width is 0.5-1.2 cm.
The venation is reticulate. The leaves on the upper side are dark green, shiny, with clearly visible depressed veins, on the lower side a little bit lighter, dull, naked. The smell is absent. The taste is strongly astringent and bitter.

Milled raw materials

The pieces of leaves of various shapes, from light green to dark green, passing through a sieve with 3 mm holes.
The smell is absent. The taste is strongly astringent and bitter.

Properties and application

Pharmacotherapeutic group. Diuretic and antiseptic effect.
Pharmacological properties.

The antiseptic action of the leaves of bearberry is due to hydroquinone, which is formed in the body during hydrolysis of arbutin and is excreted in the urine. Urine at the same time is painted in green or dark green colour. The diuretic effect of bearberry preparations is also associated with hydroquinone. Tannins contained in the broth of bearberry, have an astringent effect in the gastrointestinal tract.


The decoction of bearberry leaves is used in diseases of the urinary tract (urolithiasis, cystitis, urethritis) as a disinfectant and diuretic.

When taking large doses, vomiting, nausea, diarrhea and other side effects are possible.
Kinnikinnick leaves somewhat irritate the epithelium of the urinary system, so they are combined with plants that have anti-inflammatory, hemostatic and diuretic effects.

During pregnancy and breastfeeding.
Be careful in case of exacerbation of inflammatory processes in the kidneys.
The acid reaction of urine can be observed when eating protein food, so during treatment it is advisable to include in the diet mainly vegetable products.