Common bearberry: properties and uses

Dr. Boris Wydoff

Common bearberry is an evergreen shrub, the leaves of which are used in herbal medicine. Reference books describe arbutin, methylarbutin, tannins and other compounds. The leaves are used as an infusion and decoction as a diuretic and antiseptic remedy, primarily for diseases of the bladder and urinary tract.

What kind of plant is it and how can you recognize it?

Common bearberry (*Arctostaphylos uva-ursi*) is a small evergreen shrub from the heather family. It is also known as bear's ear or bearberry.

The plant has highly branched branches that spread along the ground. They are covered with dark brown bark and can reach 100–120 cm in length. The leaves are arranged on short petioles. They are leathery, dense, shiny, obovate, with a smooth edge. The leaves do not fall off in winter.

The flowers are small and pink. They are located at the ends of branches and collected into short drooping clusters. The corolla has a pitcher-like shape. Bearberry blooms in May — June. The fruits ripen in September. They are round, red, and have a mealy interior.

The plant grows in pine forests. Reference books specifically mention white-moss pine forests and lingonberry forests. In suitable places, bearberry can form patches.

When harvesting, it is important to identify the plant correctly. Bearberry resembles lingonberry, which often grows nearby. Lingonberry has an upright stem. Its leaves are oval, with rolled edges, and dark dotted formations are visible on the underside. Lingonberry berries are juicy inside, while bearberry fruits have mealy flesh.

According to herbal medicine reference books, the leaves — *Folium Uvae-ursi* — are used for medicinal purposes. They are the medicinal raw material of the plant.

How to distinguish bearberry from similar plants?

When collecting wild plant material, it is important not only to know the general appearance of the plant but also to pay attention to the characteristics of the leaves. Reference books specifically note that bearberry leaves should not be confused with blueberry, lingonberry and boxwood leaves.

Blueberry leaves differ because they are thin and membranous. On the underside they are dull, bluish-green, with raised reticulate veins.

Lingonberry most often causes confusion with bearberry because both plants can grow in the same places. Lingonberry leaves have brown dotted glands and sparse short hairs on the underside. The edges of the leaves are rolled, and sometimes they are finely toothed or slightly saw-like. In bearberry, the leaves are more narrowed near the petiole, and their veins are deeply sunken, making the surface look wrinkled.

Boxwood also has differences: its leaves narrow toward the top, the tip has a notch, and the veins on the upper side are raised. In addition, boxwood leaves are described as having an unpleasant smell and an unpleasant sweetish-bitter taste.

These differences have practical importance because the leaves are the medicinal raw material and must be correctly identified before use.

What makes bearberry leaves valuable?

The main attention in reference books is given to the chemical composition of the leaves. They contain arbutin and methylarbutin, tannins, flavonoids and organic acids.

One description lists gallic acid, tannins, fat, wax, resin and mineral salts. Among glycosides, arbutin, methylarbutin and ericolin are named. The presence of urson is also described.

Another reference book mentions arbutin, methylarbutin, hyperoside, pyrogallol tannins, ellagic and other organic acids. A more detailed pharmacological description also lists flavonoids, including quercetin, isoquercitrin, myricitrin, hyperoside and myricetin.

Arbutin has a special place in descriptions of the plant's effects. According to reference books, it breaks down to form hydroquinone and glucose. Methylarbutin is also able to release hydroquinone during hydrolysis.

Reference books associate the antimicrobial and antiseptic properties of the leaves with these substances. Tannins are associated with an anti-inflammatory effect. According to herbal medicine references, galenic preparations of bearberry have diuretic, anti-inflammatory and antimicrobial properties. Therefore, the main direction of using the plant is related to the urinary system.

Which substances determine the properties of the leaves?

The amounts of individual components are given with some differences in different reference books. One description indicates arbutin content of up to 3.5 %, while another gives up to 8 %. The presence of up to 35 % pyrogallol tannins is also noted.

The composition of the leaves includes organic acids, including malic, protocatechuic and formic acids. Among flavonoids, quercetin, isoquercitrin, myricitrin, hyperoside and myricetin are additionally mentioned.

Reference books associate the plant's action primarily with arbutin and tannins. Arbutin, under the influence of the enzyme arbutase, breaks down into hydroquinone and glucose, while methylarbutin also releases hydroquinone during hydrolysis.

What is bearberry used for?

Herbal medicine books describe the use of bearberry leaves for diseases of the bladder and urinary tract. The urethra and urolithiasis are also mentioned.

In one reference book, the leaves are prescribed as an astringent, anti-putrefactive and diuretic remedy for bladder catarrh and kidney bleeding. In another description, decoctions and mixtures are used as a diuretic and disinfectant remedy for inflammatory diseases of the bladder and urinary tract.

Among such conditions, reference books mention pyelitis, cystitis and urethritis. In some traditional herbal medicine formulas, bearberry is included in water decoctions that were used for kidney or bladder diseases.

There is also broader traditional use. Reference books mention the use of leaves as a diuretic remedy for kidney stones, rheumatism and gout. However, such descriptions refer to reference and traditional herbal medicine and do not replace finding the cause of symptoms.

The urinary system occupies the main place in descriptions of the plant. The diuretic, antimicrobial, antiseptic and anti-inflammatory effects described in reference books are associated with it.

How are bearberry leaves used?

Herbal medicine reference books describe infusions and decoctions made from the leaves. Decoctions are mentioned especially often.

One of the described methods has an exact proportion: a decoction or infusion in a ratio of 10:200. Another source gives the same proportion as 10 g of raw material per 200 ml of water. Take 1 tablespoon 3–4 times a day.

An old reference book also notes that the leaves are preferably used as a decoction. It separately warns that excessively large doses may cause nausea and vomiting. Therefore, the amount of raw material should not be increased at your own discretion. In herbal medicine, not only the choice of plant is important, but also following the specified preparation method.

In folk recipes, bearberry was also included in water-based herbal mixtures. In such recipes it was combined with other plants. For example, mixtures with lingonberry leaves, horsetail herb and other components are mentioned. However, the composition and purpose of such mixtures differ, so one recipe cannot be applied to all situations.

For simple use, reference books describe two main forms well — infusion and decoction. These should be considered the main methods of preparing the leaves.

How to brew bearberry correctly?

If you need a simple option, the reference book gives a proportion of 10 g of leaves per 200 ml of water. This infusion or decoction is taken 1 tablespoon 3–4 times a day.

Another reference book also directly states: a decoction or infusion is prepared in a ratio of 10:200 and taken 1 tablespoon 3–4 times a day.

You should not make the drink more concentrated simply because you want to increase its effect. The medical description of the plant specifically warns about undesirable reactions with excessively large doses.

The leaves have a pronounced astringent, slightly bitter taste. Reference books associate this with the tannins they contain.

When and how is bearberry harvested?

For medicinal purposes, bearberry leaves are collected. According to one reference book, they are harvested before or at the beginning of flowering — in May and the first half of June.

Another source describes two harvesting periods: overwintered leaves are collected before flowering, and then harvesting is possible in August, when the leaves of the current year have grown. Therefore, reference literature contains both indications for harvesting times: May and the first half of June, as well as August for later harvesting.

When collecting, the branches are cut. Before drying, browned leaves are removed. The raw material is dried outdoors.

For small leathery leaves, a practical harvesting method is described: first the plant branches are cut, then they are dried, after which the leaves are separated from the twigs. This is done by stripping, combing through the plant or threshing, followed by removal of stem parts. Final cleaning is carried out using a sieve.

Good dried raw material consists mainly of leaves. They are smooth, dense and brittle. There is almost no smell. The taste is strongly astringent and slightly bitter. During storage, the raw material is kept in a cool place protected from light.

Requirements for the quality of medicinal raw material

Reference books provide requirements for the appearance and purity of harvested raw material. The leaves should retain a green color, have characteristic density and not contain large amounts of foreign parts.

Standardization indicators are also described: the moisture content of the raw material should not exceed 12 %, and ash content — 4 %. A limited amount of leaves that have lost their green color, small and crushed parts, as well as stem parts of the plant is allowed.

Such requirements help assess the quality of raw material before use and distinguish properly prepared leaves from material with many impurities.

Common bearberry: contraindications and precautions

In old reference books, the main warning concerns the amount of raw material. Excessively large doses of leaves may cause nausea and vomiting.

Modern reference descriptions also indicate possible undesirable reactions with prolonged use. These include nausea, diarrhea and vomiting. With prolonged effects on the urinary system, increased inflammatory processes and the appearance of kidney symptoms may occur.

The reason for such attention to prolonged use is related to the plant's composition. Arbutin breaks down with the formation of hydroquinone. The reference book notes that hydroquinone is excreted in urine through the kidneys and has an irritating effect on kidney tissue.

Therefore, uncontrolled long-term use of leaves cannot be considered a safe approach. In herbal medicine references, long-term use of bearberry is usually described together with other plants that have anti-inflammatory and diuretic properties, in the form of mixtures and teas.

At the same time, any complaints from the urinary system require careful attention. The fact that a plant appears in old recipes does not mean that it should be used without determining the cause of symptoms.

If nausea, vomiting, diarrhea appear after use or unpleasant sensations from the urinary system become stronger, use should be stopped and medical help should be sought.

When a doctor is needed

For diseases of the bladder, urinary tract and kidneys, it is important to first determine the cause of complaints. Herbal medicine does not replace examination and medical recommendations. It is especially important to see a doctor in case of severe, prolonged or worsening symptoms, the appearance of new complaints or deterioration of health.

A consultation is also needed if an unusual reaction occurs after using the plant, if a person regularly takes medications or has a chronic disease. Special caution is needed in situations where the safety of a herbal remedy for a particular person should be determined by a doctor.

If there are any doubts about using an infusion or decoction, it is better to discuss it with a specialist before starting use.

Boris Wydoff — naturopath and author, Ph.D. in nutrition. For over fifty years I have helped people restore health through nutrition, cleansing and the power of the mind — in Europe, America and Asia. About the author →

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