​Arctostaphylos (Bearberry)

Arctostaphylos (Bearberry)

Product Name: Медвежье ушко, Arctostaphylos uva-ursi, Bärentraube, Uva de oso, Busserole, عنب الدب, หญ้าหมี, Ayıquloq, Аю кулагы, Ayıqulağı, Ангурихи хирс, Meškinė uoga, Lāču oga, Ведмежі вушка, Ayıqulağı, דובדבן הדוב

Synonyms: толокнянка, медвежья трава, медвежий виноград, bearberry, kinnikinnick, upland cranberry, Bärentraube, Sandbeere, gayuba, uva de oso, raisin d'ours, buisson aux ours, عنب الدب, หญ้าหมี

Parts Used: leaves, shoots, berries, roots, branches, flowers, seeds.

Main Indications for Use of Bearberry (Arctostaphylos uva-ursi): Interstitial cystitis, bacterial urethritis, chronic pyelonephritis, acute pyelitis, urolithiasis with an infectious component, prostatic hyperplasia with dysuric disorders, postpartum urinary tract infection, vaginal candidiasis with bladder involvement, purulent cervicitis, acute bacterial prostatitis.

Use of Bearberry (Arctostaphylos uva-ursi) in Mixtures and Complexes: Kidney sand without inflammatory syndrome, gout, edematous syndrome in heart failure, irritable bladder syndrome, atonic urinary incontinence, benign prostatic hyperplasia without signs of infection, recurrent cystitis in postmenopause, nocturnal enuresis in children.

Pharmacological Properties of Bearberry (Arctostaphylos uva-ursi): diuretic, antiseptic, astringent, anti-inflammatory, antibacterial, antimicrobial, antioxidant, nephroprotective, spasmolytic, mild immunomodulatory, soothing, enveloping, wound-healing, fungistatic, adsorbing, hypoazotemic.

Dosage of Pharmaceutical Forms — Bearberry (Arctostaphylos uva-ursi)

Powder — Bearberry (Arctostaphylos uva-ursi)

Indications (Powder): interstitial cystitis, chronic bacterial urethritis, acute pyelonephritis, prostatic hyperplasia with dysuria, purulent cervicitis, vaginal candidiasis.

Standard Dosage (Powder): 1 gram of powder 3 times a day 20 minutes before meals, washed down with warm water (200 milliliters), course — 14 days.

Enhanced Dosage (Powder): 2 grams of powder 3 times a day, for acute forms of pyelonephritis, recurrent cystitis with purulent microflora, microbial prostatitis.

Maximum Dosage (Powder): 2.5 grams of powder 3 times a day, no more than 10 days, permissible for chronic pyelonephritis with a high bacterial load.

Preventive Dosage (Powder): 1 gram of powder 1 time a day in the morning on an empty stomach, 10 days a month, for patients with recurrent cystitis, a tendency to urethritis, women in postmenopause.

Pediatric Dosage (Powder): from 12 years of age, with a body weight of more than 35 kilograms — 0.5 grams of powder 2 times a day, for cystitis and urethritis.

Contraindications (Powder): pregnancy, acute gastritis with increased acidity, gastric and duodenal ulcer, acute renal failure. Data on contraindications during lactation and in children under 12 years of age have not been scientifically registered.

Side Effects (Powder): dyspeptic disorders, metallic taste in the mouth, green coloration of urine, in case of overdose — irritation of the gastric mucosa.

Adjustment for Patient Body Weight: with a body weight below 60 kilograms — reduce the dosage by 25%, with a body weight above 90 kilograms — increase the dosage by 25%.

Preparation method (Powder): 100 grams of powder is obtained by grinding dried leaves of Arctostaphylos uva-ursi in a metal or ceramic mortar, then sifting through a sieve with a mesh size of no more than 0.5 millimeters. Store in dark glass containers with a tightly closing lid.

Storage Conditions and Shelf Life (Powder): Store in a dry, cool place at a temperature not exceeding 25 degrees Celsius, in a dark glass container shielded from electromagnetic fields, shelf life — 12 months. After opening the package, use within 60 days.

Dry Extract — Bearberry (Arctostaphylos uva-ursi)

Indications (Dry Extract): acute bacterial urethritis, chronic cystitis, prostatic hyperplasia with infection, interstitial cystitis, inflammation of the bladder mucosa, microbial prostatitis.

Standard Dosage (Dry Extract): 150 milligrams of dry extract 2 times a day, 30 minutes before meals, course — 14–21 days.

Enhanced Dosage (Dry Extract): 200 milligrams 3 times a day for acute inflammatory diseases of the bladder and for combined urethrocystitis.

Maximum Dosage (Dry Extract): 250 milligrams 3 times a day for 7 days, for exacerbations with bacteriuria above 105 CFU/ml.

Preventive Dosage (Dry Extract): 100 milligrams 1 time a day for 14 days, repeat every month, for chronic cystitis, bladder hypotonia, in the climacteric period.

Pediatric Dosage (Dry Extract): from 14 years of age and body weight more than 45 kilograms — 100 milligrams 1 time a day for chronic cystitis.

Contraindications (Dry Extract): acute form of gastritis, pregnancy, pronounced irritation of the bladder, chronic renal failure. There are no reliable data on use in children under 14 years of age and during lactation.

Side Effects (Dry Extract): bitterness in the mouth, nausea, feeling of tightness in the stomach, with prolonged use — irritation of the mucosa.

Adjustment for Patient Body Weight: with a weight below 60 kilograms — 75% of the recommended dose, with a weight above 90 kilograms — an increase in dosage by 25%.

Preparation method (Dry Extract): To obtain 100 grams of dry extract, 500 grams of ground leaves of Arctostaphylos uva-ursi are used. Extraction is carried out for 6 hours at a temperature of 65 degrees Celsius with 70% ethanol in a ratio of 1:5. After filtration, the solution is evaporated under reduced pressure to a thick consistency, then dried in a spray dryer until a powdery mass is obtained.

Storage Conditions and Shelf Life (Dry Extract): Store in a tightly closed hermetic container, away from light and moisture, at a temperature of 15–20 degrees Celsius, without access to oxygen and sources of EMF. Shelf life — 18 months. After opening, use within 30 days.

Alcohol Tincture — Bearberry (Arctostaphylos uva-ursi)

Indications (Alcohol Tincture): acute and chronic cystitis, bacterial urethritis, prostatitis with an inflammatory component, prostatic hyperplasia with infection, purulent pyelonephritis.

Standard Dosage (Alcohol Tincture): 25 drops of tincture per 50 milliliters of water 3 times a day 30 minutes before meals, course — 10–14 days.

Enhanced Dosage (Alcohol Tincture): 30 drops 3 times a day for acute purulent cystitis, exacerbation of chronic prostatitis, bladder infection in men.

Maximum Dosage (Alcohol Tincture): 40 drops 3 times a day, no more than 7 days in a row, for bacterial pyelonephritis with pronounced dysuria.

Preventive Dosage (Alcohol Tincture): 15 drops of tincture 1 time a day in the morning, diluted in water, 10 days a month. Suitable for the prevention of relapses in patients with chronic urethritis, cystitis in the climacteric period, reduced secretion of mucous membranes.

Pediatric Dosage (Alcohol Tincture): is not recommended for children under 14 years of age due to the ethanol content. For older adolescents — 10 drops 2 times a day with a body weight from 45 kilograms.

Contraindications (Alcohol Tincture): pregnancy, lactation period, childhood under 14 years, chronic alcoholism, hepatitis, liver cirrhosis, psychoses. In patients with peptic ulcer, use with caution.

Side Effects (Alcohol Tincture): nausea, dizziness, stomach irritation, metallic taste, increased diuresis, allergic rash.

Adjustment for Patient Body Weight: with a weight below 60 kilograms — no more than 15 drops per single dose, with a weight above 90 kilograms — up to 40 drops.

Preparation method (Alcohol Tincture): 100 grams of ground dry leaves of Arctostaphylos uva-ursi are infused in 70% ethyl alcohol (500 milliliters) in a glass hermetic container in the shade at a temperature of 18–25 degrees Celsius for 10 days, periodically shaking. Then filtered and poured into dark glass vials.

Storage Conditions and Shelf Life (Alcohol Tincture): Store at a temperature of 15 to 25 degrees Celsius, in a dark place, tightly closed, away from heat sources and electromagnetic radiation. Shelf life — 24 months. After opening, use within 60 days.

Oil Infusion — Bearberry (Arctostaphylos uva-ursi)

Indications (Oil Infusion): inflammatory processes of the skin and mucous membranes, irritation, edema, combined vaginitis, prevention of recurrences of vaginal candidiasis, reduced local immunity, hormone-dependent atrophic changes.

Standard Dosage (Oil Infusion): application — 2 times a day (morning and evening) to the affected areas, 5–7 days in a row.

Enhanced Dosage (Oil Infusion): applications 3 times a day for pronounced inflammation of the mucous membranes, irritation and edema, including combined vaginitis.

Maximum Dosage (Oil Infusion): up to 4 applications per day is permissible for a short course (no more than 3 days) for erosive-purulent processes.

Preventive Dosage (Oil Infusion): 1 time a day in the evening for 5 days after the end of menstruation for the prevention of recurrences of vaginal candidiasis, with reduced local immunity, with hormone-dependent atrophic changes.

Pediatric Dosage (Oil Infusion): is used in girls from 10 years of age if necessary for the treatment of external genitalia — 1 time a day, only as prescribed by a doctor.

Contraindications (Oil Infusion): individual intolerance, deep skin ulcers, acute purulent dermatoses. Data on contraindications during pregnancy, lactation and in childhood have not been scientifically registered.

Side Effects (Oil Infusion): skin irritation, redness, allergic reaction in the form of itching.

Adjustment for Patient Body Weight: no correction is required, it is applied externally based on the area of the treated surface.

Preparation method (Oil Infusion): 100 grams of dry ground leaves of Arctostaphylos uva-ursi are poured with 500 milliliters of natural coconut oil (without flavorings). Placed in a water bath at a temperature of 45–50 degrees Celsius for 3 hours. Infused for 48 hours at room temperature in a tightly closed jar, then filtered through cloth or gauze. Store in glass containers.

Storage Conditions and Shelf Life (Oil Infusion): Store in a cool, dark place, at a temperature of 10 to 20 degrees Celsius. Preferably use within 6 months. After opening, use within 30 days. Avoid sunlight and exposure to electromagnetic radiation.

Vaginal Suppository — Bearberry (Arctostaphylos uva-ursi)

Indications (Vaginal Suppository): vaginal candidiasis, bacterial vaginosis, atrophic colpitis, cervicitis, vulvovaginitis, vaginal dysbiosis, cervical erosion.

Standard Dosage (Vaginal Suppository): 1 suppository at night, intravaginally, course — 7–10 days.

Enhanced Dosage (Vaginal Suppository): 1 suppository 2 times a day (morning and evening) for pronounced bacterial inflammation or candidiasis with abundant discharge.

Maximum Dosage (Vaginal Suppository): no more than 3 suppositories per day, course no more than 5 days, for acute purulent colpitis with concomitant cervicitis.

Preventive Dosage (Vaginal Suppository): 1 suppository 1 time in 3 days for 2 weeks after an antibacterial course or menstruation for chronic colpitis, in menopausal women.

Pediatric Dosage (Vaginal Suppository): is permissible from 14 years of age, 1 suppository at night for laboratory-confirmed vaginal dysbiosis, under medical supervision.

Contraindications (Vaginal Suppository): intolerance to components, acute bleeding, pregnancy up to 12 weeks. Data on contraindications during lactation and in girls under 14 years of age have not been scientifically registered.

Side Effects (Vaginal Suppository): local burning, itching, rare cases of contact dermatitis with individual sensitivity.

Adjustment for Patient Body Weight: not required, suppositories are used locally.

Preparation method (Vaginal Suppository): To prepare 100 grams of the base, use: cocoa butter — 70 grams, dry extract of Arctostaphylos uva-ursi — 20 grams, beeswax — 10 grams. Cocoa butter and wax are melted in a water bath at a temperature not exceeding 50 degrees Celsius, then the extract is introduced and thoroughly mixed. Poured into vaginal molds with a volume of 2 grams, cooled until solidified.

Storage Conditions and Shelf Life (Vaginal Suppository): Store in the refrigerator at a temperature of +2 to +8 degrees Celsius in a hermetic package. Avoid exposure to direct light and EMF sources. Shelf life — 6 months. After opening the blister, use within 5 days.

Rectal Suppository — Bearberry (Arctostaphylos uva-ursi)

Indications (Rectal Suppository): acute proctitis, hemorrhoids with inflammation, anal fissures, paraproctitis, bacterial infection of the rectum, secondary proctitis in prostatitis.

Standard Dosage (Rectal Suppository): 1 suppository rectally at night, course — 7 days.

Enhanced Dosage (Rectal Suppository): 1 suppository 2 times a day for a pronounced inflammatory component or exacerbation of chronic paraproctitis.

Maximum Dosage (Rectal Suppository): 3 suppositories per day (1 every 8 hours) no more than 3 days in a row, for purulent proctitis with pain syndrome.

Preventive Dosage (Rectal Suppository): 1 suppository 1 time in 3 days for 10 days for recurrent hemorrhoids, in patients with chronic constipation and inflammation of the rectal mucosa.

Pediatric Dosage (Rectal Suppository): is permissible from 10 years of age, with a body weight from 30 kilograms — ½ suppository 1 time a day, for anal fissures.

Contraindications (Rectal Suppository): acute bleeding from the rectum, tumor processes, individual intolerance. Data on contraindications during pregnancy and lactation have not been registered.

Side Effects (Rectal Suppository): feeling of burning in the rectum, rare cases of false urges to defecate, contact hyperemia.

Adjustment for Patient Body Weight: with a weight below 50 kilograms — use ½ suppository, with a weight above 90 kilograms — increase the volume of the suppository by 25%.

Preparation method (Rectal Suppository): To prepare 100 grams, use: coconut oil — 60 grams, dry extract of Arctostaphylos uva-ursi — 25 grams, lanolin — 15 grams. The oil and lanolin are melted in a water bath (45–50 °C), the extract is added with constant stirring. The mixture is poured into rectal molds of 2 grams. Cooled until completely solidified.

Storage Conditions and Shelf Life (Rectal Suppository): Store in the refrigerator at a temperature of +2…+8 °C in the original package. Avoid overheating and contact with moisture. Shelf life — up to 6 months. After opening the package, use within 5 days.

Ointment — Bearberry (Arctostaphylos uva-ursi)

Indications (Ointment): contact dermatitis, eczema, psoriasis with secondary infection, pustular rash, skin fissures, atopic dermatitis, bacterial inflammation of the skin.

Standard Dosage (Ointment): apply a thin layer to the affected areas of the skin 2 times a day, course — 7–10 days.

Enhanced Dosage (Ointment): 3 times a day in the presence of exudate, secondary infection or inflammatory nodules.

Maximum Dosage (Ointment): up to 4 applications per day for a limited area of lesion (no more than 10% of the body surface), course — no more than 5 days.

Preventive Dosage (Ointment): 1 time a day for 5 days a month for a chronic tendency to microbial eczema or dry skin, for patients with allergic skin diseases.

Pediatric Dosage (Ointment): from 3 years of age — 1 time a day on limited areas, with a body weight from 15 kilograms, under medical supervision.

Contraindications (Ointment): acute purulent dermatoses, weeping ulcers, individual intolerance to components. Data on contraindications during pregnancy and lactation are absent.

Side Effects (Ointment): allergic reaction, contact dermatitis, skin irritation in case of overdose.

Adjustment for Patient Body Weight: not required.

Preparation method (Ointment): For 100 grams of ointment, use: dry extract of Arctostaphylos uva-ursi — 20 grams, coconut oil — 50 grams, anhydrous lanolin — 20 grams, beeswax — 10 grams. The components are melted in a water bath (temperature 45–50 °C), thoroughly mixed, cooled with constant stirring to a viscous consistency.

Storage Conditions and Shelf Life (Ointment): Store at a temperature of +5 to +15 degrees Celsius in a tightly closed dark glass jar. Avoid exposure to light and heat. Shelf life — 6 months. After opening, use within 30 days.

Cream — Bearberry (Arctostaphylos uva-ursi)

Indications (Cream): hyperpigmentation, post-acne, sun spots, photoaging, age-related skin changes, inflammatory processes of the skin of the face and neck.

Standard Dosage (Cream): apply 1 time a day in the evening to cleansed skin, with light massage movements, avoiding the area around the eyes, course — 21 days.

Enhanced Dosage (Cream): 2 times a day (morning and evening) for pronounced hyperpigmentation, post-inflammatory spots, photodermatosis.

Maximum Dosage (Cream): 3 times a day, spot application to problem areas, no more than 10 days in a row, during the active phase of inflammation and pigmentation disorders.

Preventive Dosage (Cream): 1 time a day every other day for 30 days — to maintain an even skin tone, especially for chronic hyperpigmentation in patients over 40 years of age.

Pediatric Dosage (Cream): is not used in children under 12 years of age. In adolescents from 12 years of age — no more than 1 time a day, spot application for post-acne.

Contraindications (Cream): individual intolerance, active dermatitis, presence of open wounds. Data on contraindications during pregnancy and lactation are absent.

Side Effects (Cream): feeling of skin tightness, slight tingling, allergic rash with increased sensitivity.

Adjustment for Patient Body Weight: not required.

Preparation method (Cream): For 100 grams of cream: distilled water — 60 grams, coconut oil — 15 grams, emulsifier (natural lecithin) — 5 grams, dry extract of Arctostaphylos uva-ursi — 10 grams, vegetable glycerin — 5 grams, lavender essential oil — 5 drops. The aqueous and oil phases are heated separately to 60 °C, then slowly combined while whipping. After cooling, the extract and aromatic components are added.

Storage Conditions and Shelf Life (Cream): Store in the refrigerator at a temperature of +2 to +8 degrees Celsius, in a hermetic package. Avoid exposure to light. Shelf life — 3 months. After opening, use within 20 days.

Serum — Bearberry (Arctostaphylos uva-ursi)

Indications (Serum): melasma, lentigo, hyperpigmentation after acne, photodamage of the skin, post-inflammatory hyperpigmentation, uneven skin tone.

Standard Dosage (Serum): apply 1–2 drops of serum spot-on or to the entire skin of the face 1 time a day in the evening to cleansed skin, course — 14–28 days.

Enhanced Dosage (Serum): 2 times a day (morning and evening) to pigmented areas, for persistent melasma or lentigo.

Maximum Dosage (Serum): up to 3 applications per day, no more than 10 days in a row, exclusively spot-on to pigment spots.

Preventive Dosage (Serum): 1 time a day at night, 10 days a month, for the prevention of pigmentation disorders in individuals with phototype II–IV, including after chemical peels.

Pediatric Dosage (Serum): is permissible from 12 years of age, only spot-on, 1 time a day, for post-inflammatory hyperpigmentation.

Contraindications (Serum): individual intolerance, fresh burns, open wounds. Data on contraindications during pregnancy and lactation have not been scientifically registered.

Side Effects (Serum): feeling of tingling, irritation, peeling with prolonged use, photosensitivity when going out into the sun without protection.

Adjustment for Patient Body Weight: not required.

Preparation method (Serum): For 100 grams: chamomile hydrolate — 60 grams, dry extract of Arctostaphylos uva-ursi — 5 grams, hyaluronic acid (low molecular weight) — 0.5 grams, glycerin — 10 grams, plant-derived preservative — 1 gram, the rest — distilled water. Mixing occurs at a temperature not exceeding 35 °C using sterile instruments. The resulting mass is packaged in glass vials with a pipette.

Storage Conditions and Shelf Life (Serum): Store in the refrigerator, at a temperature of +2 to +8 degrees Celsius, in a tightly closed glass container protected from light. Shelf life — 45 days. After opening, use within 14 days.

Toxicity and Biosafety of Bearberry (Arctostaphylos uva-ursi)

The toxicity assessment of Arctostaphylos uva-ursi shows a moderately low level of acute toxicity. The main active substance — arbutin — is hydrolyzed during metabolism in the body with the release of hydroquinone, which can have a toxic effect at high doses and with prolonged use. According to animal studies, oral administration of Arctostaphylos uva-ursi extract in rats showed that the LD50 is more than 4,000 mg/kg of body weight, which qualifies it as a non-toxic substance for short-term use. With chronic use of high doses, damage to liver tissue and kidneys is possible, especially with prolonged intake or violation of the dosage regimen. Studies also show that arbutin can accumulate with abuse of the plant, especially when taking concentrated extracts. Nevertheless, in therapeutic doses, Arctostaphylos uva-ursi is considered safe for course use up to 14 days

Reference: https://www.sciencedirect.com/...

Pharmacodynamics — Bearberry (Arctostaphylos uva-ursi)

The pharmacodynamic activity of Arctostaphylos uva-ursi is determined mainly by the content of phenolic glycosides (primarily arbutin), flavonoids, tannins, and organic acids. The main mechanism of action is associated with the cleavage of arbutin to the active metabolite — hydroquinone, which exhibits a pronounced inhibitory effect on bacterial enzymes and suppresses the growth of gram-positive and gram-negative microorganisms. At the same time, the effect is realized predominantly at the level of the epithelium of mucous membranes, especially with an alkaline reaction of the medium. The plant has a complex modulating effect on the urogenital and skin systems, including antiseptic, astringent, antioxidant, and moderately antispasmodic action. Tannin compounds contained in the leaves exhibit a high ability to precipitate proteins, which contributes to the creation of a protective film on the surface of tissues, reduces the permeability of the vascular wall, and reduces the local inflammatory reaction. This effect is realized predominantly at the local level, especially with external or mucosal application. Flavonoids and phenolic acids have an antioxidant effect by neutralizing free radicals and stabilizing cell membranes. The mechanisms include inhibition of lipid peroxidation, as well as enhancement of the activity of endogenous antioxidant enzymes (catalase, superoxide dismutase, etc.). This contributes to a cytoprotective effect on epithelial cells and parenchymal organs.

An indirect effect on the immune system is observed due to the inhibition of the production of inflammatory mediators such as prostaglandins and interleukins. The experimentally confirmed antiproliferative effect is due to phenolic compounds that modulate the activity of tyrosinase and other enzymes involved in melanogenesis. This explains the use of the plant raw material for cosmetic purposes.

The systemic pharmacological targets are the mucosa of the urinary tract, the epithelium of the skin and vaginal area, the enzyme systems of the microflora, as well as receptors sensitive to phenolic compounds. A mild sedative effect has also been noted, associated with flavonoids and their influence on the central mechanisms of regulation of autonomic tone.

In an alkaline urine environment, an enhancement of the local activity of phenolic metabolites is observed. Therefore, the effectiveness of the component largely depends on the physiological pH. Biochemical studies also demonstrate antilysosomal and anticollagenase activity, contributing to the stabilization of connective tissue.

Studies confirm the possibility of inhibiting the growth of opportunistic fungi and resistant bacterial strains, especially under conditions of combined use with other phyto-components. This gives grounds to classify Arctostaphylos uva-ursi as a plant with a broad spectrum of antimicrobial activity, acting at the systemic and local levels without pronounced suppression of the body's own microflora.

References:
https://pubmed.ncbi.nlm.nih.go...
https://onlinelibrary.wiley.co...
https://www.sciencedirect.com/...
https://link.springer.com/arti...

Pharmacokinetics — Bearberry (Arctostaphylos uva-ursi)

The pharmacokinetic characteristics of the active components of Arctostaphylos uva-ursi are mainly due to the presence of phenolic glycosides (primarily arbutin), as well as flavonoids and tannins. When administered orally, arbutin is absorbed in the upper gastrointestinal tract in an unchanged form. Absorption proceeds relatively quickly, after which the substance is transported with the blood flow to the systemic circulation.

The metabolism of arbutin occurs mainly in the liver and, to a lesser extent, in the kidneys and intestines. As a result of hydrolysis under the action of glycosidases of the microflora and liver enzymes, hydroquinone is released, which has a pronounced local and systemic antiseptic effect. Hydroquinone is further subjected to glucuronidation and sulfation with the formation of water-soluble conjugates that are excreted in the urine.

With transdermal and mucosal administration (ointment, cream, suppositories), the bioavailability of the active components is limited but sufficient to achieve a local effect. Tannins mainly act locally and are practically not absorbed, creating a protective biofilm. Flavonoids and organic acids can penetrate epidermal and mucosal tissues, providing a local anti-inflammatory and antioxidant effect.

The distribution of components in tissues is characterized by moderate affinity for mucous membranes, skin, epithelial and connective tissue. Accumulation in organs and systems is minimal, except for metabolites capable of lingering in the urinary tract. With intravaginal administration, a local effect is observed without significant systemic distribution.

The excretion of the main metabolites occurs mainly through the kidneys, in the form of sulfate and glucuronide compounds. A small amount can leave the body through bile, especially with prolonged use. The participation of the liver in metabolism is moderately pronounced, which makes the plant relatively safe with preserved liver function. Interaction with the intestinal microflora affects the biotransformation of arbutin and flavonoids, modulating the overall effect depending on the composition of the microbiota.

Overall, the pharmacokinetic profile indicates a predominant local and organ-specific action with moderate systemic absorption and rapid excretion of active metabolites, especially with short courses.

References:
https://www.tandfonline.com/do...
https://pubchem.ncbi.nlm.nih.g...
https://www.sciencedirect.com/...
https://www.ncbi.nlm.nih.gov/p...

Mechanisms of Action and Scientific Rationale — Bearberry (Arctostaphylos uva-ursi)

The pharmacological action of Arctostaphylos uva-ursi is due to a complex of biologically active substances, primarily arbutin, which is metabolized to hydroquinone, as well as flavonoids, tannins, phenolcarboxylic acids, and triterpenes. Arbutin, a glycoside of hydroquinone, after absorption undergoes biotransformation in the liver and intestines with subsequent release of the active form — free hydroquinone, which has antibacterial activity. The target of hydroquinone action is bacterial enzyme systems, in particular, inhibition of dihydrofolate reductase and disruption of cell wall synthesis.

Phenolic compounds, including gallic and ellagic acids, demonstrate antioxidant activity due to direct inactivation of reactive oxygen species and suppression of lipid peroxidation. These compounds indirectly affect signaling pathways, including suppression of the expression of the transcription factor NF-κB, which regulates the expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β). Similar properties have been confirmed in vitro on models of the inflammatory response of macrophages.

Flavonoids contained in the leaves (including quercetin and myricetin) exhibit inhibitory activity against the enzymes cyclooxygenase-2 (COX-2) and lipoxygenase (LOX), which confirms the presence of anti-inflammatory potential. Inhibition of prostaglandin production and a decrease in the expression of adhesion molecules on the surface of endothelial cells are also observed. These mechanisms contribute to a decrease in the migration of neutrophils into inflamed tissues.

Tannins, represented mainly by gallotannin, carry out a protective effect on mucous membranes due to the formation of a film and denaturation of proteins of surface cells. This action is also accompanied by a decrease in capillary permeability and a decrease in the secretion of pro-inflammatory mediators, including histamine. With local application, these compounds suppress the activity of microbial enzymes involved in the pathogenesis of skin and urogenital disorders.

Thus, the combination of phenolic glycosides, flavonoids, and tannins in the composition of Arctostaphylos uva-ursi provides a multicomponent action on enzyme systems, cellular receptors, cytokine cascades, and the structure of epithelial and immune cells. This forms a scientifically substantiated basis for the pharmacological application of this plant in systemic and local therapy.

References:
https://pubmed.ncbi.nlm.nih.go...
https://www.sciencedirect.com/...
https://www.ncbi.nlm.nih.gov/p...
https://link.springer.com/arti...
https://pubchem.ncbi.nlm.nih.g...

Synergy — Bearberry (Arctostaphylos uva-ursi)

The pharmacological synergy of Arctostaphylos uva-ursi has been confirmed in combination with a number of plant and natural compounds. In particular, when combined with extracts of Urtica dioica, Equisetum arvense, Vaccinium macrocarpon, and Taraxacum officinale, potentiation of diuretic and antiseptic activity is observed due to additive inhibition of microorganism growth and enhanced elimination of metabolic products from the urinary system. The mechanism of this interaction is realized through co-inhibition of the adhesion of bacterial strains to the urothelium, a decrease in the expression of inflammatory mediators, and enhanced synthesis of protective mucins.

In vitro experiments show that the combination of Arctostaphylos uva-ursi with flavonoid complexes (e.g., rutin, hesperidin, apigenin) enhances antioxidant and anti-inflammatory action. This is due to the influence on common signaling pathways: suppression of COX-2 and NF-κB activity, as well as stabilization of lysosomal membranes and a decrease in the release of pro-inflammatory cytokines.

An additional modulating interaction has been identified when combined with Salix alba bark and Curcuma longa extract, which is due to the simultaneous influence on the enzyme cascades of cyclooxygenase and lipoxygenase. Such interaction enhances the suppression of prostaglandin and leukotriene synthesis, leading to a sustained anti-inflammatory response at the cellular level. Synergism with bioflavonoids of citrus origin is also noted, manifested in a decrease in capillary permeability and stabilization of the endothelium.

At the level of immune regulation, potentiation of antimicrobial activity has been revealed with combined use with compounds contained in Echinacea purpurea and Andrographis paniculata. This has been confirmed in studies involving monocytic and macrophage cell lines, where synergistic suppression of TNF-α and IL-1β production was observed, as well as a decrease in the expression of Toll-like receptors.

Finally, synergy with antimelanogenetic components (in particular, with Glycyrrhiza glabra extract and vitamin C) enhances the inhibition of tyrosinase, reducing melanin production in keratinocytes. This interaction is tissue-specific in nature, predominantly in the area of the dermal-epidermal junction.

References:
https://pubmed.ncbi.nlm.nih.go...
https://www.sciencedirect.com/...
https://link.springer.com/arti...
https://www.ncbi.nlm.nih.gov/p...
https://onlinelibrary.wiley.co...

Geography of Use and Traditional Medicine — Bearberry (Arctostaphylos uva-ursi)

Bearberry, known in folk tradition as bear's ear, has an extensive geography of ethnomedical use, covering Europe, Siberia, the Caucasus, Central Asia, North America, and certain regions of East Asia. The plant was most widely used in the folk healing practices of Slavic, Germanic, Finno-Ugric, Native American, and North Asian peoples. In the Russian and Belarusian healing tradition, bearberry leaves were used in the form of decoctions and infusions, especially in combination with other diuretic plants. In Siberia and the Urals, the plant was used by hunters and reindeer herders, who brewed it in field conditions as a strong infusion, considering it a "plant of purity."

In the culture of North American Indians (Cheyenne, Cherokee, Navajo), bearberry was part of smoking mixtures (kinnikinnick), used both in ritual ceremonies and in everyday life. Its leaves were dried and mixed with red willow bark or other plants. The plant was also used externally in the form of poultices and compresses. In the Cherokee tradition, bearberry was considered "bear medicine" and a symbol of purification and abstinence; it was used for symbolic purifications before hunting or the birth of a child.

In the Caucasus and Armenia, bearberry was used as part of multicomponent preparations, especially in mountainous regions where the plant was collected on rocky slopes. In Armenian folk medicine, the leaves were used not only in decoctions but also as bases for ointments applied to the skin. In the culture of some Muslim peoples, the plant was associated with "purity of the body" and was included in women's hygiene rituals.

Scandinavian peoples (in particular, the Sami) used the leaves and berries of bearberry in the form of a chewing mass and infusion. It was included in the list of traditional remedies mentioned in Swedish and Norwegian herbals of the 17th–18th centuries. In Lithuanian and Latvian village practices, the plant was often used in combination with birch and nettle leaves, especially after bath procedures.

In the folklore of northern Europe, bearberry is mentioned as a plant protecting against "defilement." It was placed under the pillow of a woman in labor or used in fumigating a room after illness. In some regions, it was considered a plant-guide between worlds and was used in divinatory practices and water fortune-telling.

In Tibetan medicine and the traditional pharmacopoeia of China, Arctostaphylos uva-ursi did not have a central status, but analogous plants were used as astringent and diuretic components in multi-plant recipes. In Tibetan zoomorphic symbolism, the plant was associated with the bear as a bearer of the energy of the earth and protection.

Bearberry is mentioned in ancient Slavic herbals of the 16th century. It was first described as a separate medicinal unit in the "Pharmaceutical Decree" of Peter I (1721), and later included in Russian pharmacopoeias of the 19th century as officinalis. In non-medical practice, the plant was used in rites of purification of the dwelling, burned for fumigation after a serious illness, and bunches were placed above the entrance door for protection from the "evil eye."