Busserole, bear grape with gargantuan properties

Bearberry is one of the great omissions from medical literature throughout antiquity. The Middle Ages fared little better, considering that the earliest documents relating to it date back only to the 12th century: some English books mention its use, and it is even mentioned in a 13th-century Welsh herbarium entitled Les médecins de Myddfai (The Doctors of Myddfai). In France, it was Rabelais (a doctor and writer) who first highlighted the diuretic effects of bearberry in his literary work Gargantua, describing Pantagruel suffering from a urinary infection.

What is bearberry?

Bearberry, or Arctostaphylos uva-ursi, is a small shrub in the Ericaceae family, native to the United States and widespread in mountainous regions in the northern hemisphere. In France, it is mainly found in thesouthern hemisphere and in mountainous areas. Appearing from May to July, small pink bell-shaped flowers accompany its spatula-shaped evergreen leaves. These flowers form clusters and produce red drupes, hence the nickname “bear’s grape“.

Bearberry’s drug is its leaves. They are mainly composed ofarbutin (or arbutoside), a substance with therapeutic effects. The leaves are harvested in summer and dried for medicinal use. Bearberry is known for its use in the treatment of moderate urinary tract and bladder disorders. However, there is not yet sufficient clinical evidence to support this use.

The plant is a creeping sub-shrub, often forming cushion-like clumps. Its thin bark exfoliates easily. It is considered to be a ground-covering coloniser. Its simple, alternate, thick, leathery leaves have a shiny, oval-oblong blade.

Bearberry flowers are radially symmetrical and pentamerous, with a five-toothed calyx and a pink or pinkish-white ureate corolla. It has ten stamens and a multi-ovulated supere ovary.

The fruit are bright red drupes when ripe, containing five single-seeded nucules. These berries are eaten by bears and are decorative, but mealy and tasteless. Thearbutoside in the leaves is a phenolic heteroside, absorbed in the intestine and hydrolysed into β-D-Glucopyranose and hydroquinone, which has an antiseptic action on the kidneys. More than half of the arbutoside ingested is eliminated in the form of glucuronide and hydroquinone sulphate. Bearberry also contains gall tannins and flavonoids.

A little history

In the 20th century, Botan reaffirmed the plant’s diuretic and antiseptic powers. He wrote that “this dual property is put to good use whenever it is necessary to cure inflammations accompanied by purulence”. Leclerc, who was well aware of what his predecessors had observed about bearberry, made the following observation: the leaves of the pear tree act in the same way as those of bearberry. This is what he said: “their infusion behaves like a good diuretic, capable of exerting on the urine an antiputrid action similar to that ofuva-ursi: it is therefore used in cystitis, bacteriuria and urinary lithiasis; under its influence, the volume of the urine increases, the excreted liquid becomes clearer and thus loses its fetidity and the painful phenomena of which the bladder is the seat are sedated”.

Charles de Barbeyrac (1629-1699) also recommended bearberry “to soothe nephritic pain and remove mucus and sand from the urine”. But it wasn’t until the Viennese doctor Dehaen – who undoubtedly best appreciated the therapeutic value of bearberry – that this plant was recommended for “all those with prolonged and abundant suppuration, resistant to other therapeutic means, in the urinary system, kidneys, ureter, bladder, urethra, scrotum and perineum, without any venereal traces and without obvious signs of a calculus”, he wrote in his Ratio medendi in nosocomio practico in 1758.

Following the establishment of these medicinal properties, many practitioners followed in Dehaen ‘s footsteps to test this plant, said to be the best remedy for suppurations of the urinary tract.

What are the main pharmacological properties of Bearberry leaves?

In vitro, thefree hydroquinone in Bearberry has an effective antibacterial action on bacteria such as Escherichia Coli, Proteus Vulgaris, Staphylococcus aureus and Enterococcus Vulgaris.Antibacterial efficacy depends on the bioavailability of hydroquinone and its conjugated form. In the past, it was recommended thaturine should be alkalinised to promote hydrolysis ofcomplexed hydroquinone into free hydroquinone. However, recent studies by Garcia De Arriba have revealed that it is the bacteria themselves that release the free form. In fact, in an environment where coccobacilli were cultured withconjugated hydroquinone, it was observed that this was transformed into free hydroquinone in the intracellular medium of the bacteria.

Urinary antiseptic properties

These properties are linked to the activity ofarbutin, a powerful urinary disinfectant and anti-inflammatory active on Escherichia coli, the main germ responsible for urinary tract infections.Arbutin is only metabolised in the urinary tract, where it is hydrolysed into glucose and hydroquinone (a substance very similar to phenol), a powerful antiseptic. This transformation therefore takes place in alkaline or alkalinised urine.

Hydroquinone, phenolic acids and pikeoside act synergistically on a wide range of germs, including Escherichia coli, Staphylococcus aureus, Mycoplasma, Pseudomonas aer, Proteus vulg, Klebsiella pneumonia, Enterococcus faecal and Streptococcus. These active ingredients are also antimycotic(candida albicans) and virostatic.

In addition, the leaves are antimicrobial in vitro and in vivo against numerous germs(Candida, Staphylococcus, Escherichia, Salmonella).

Anti-inflammatory, analgesic, astringent and decongestant properties for the urinary tract

Bearberry’s therapeutic properties are partly due to the presence ofiridoids andallantoin, which are healing and reconstituting agents for the epithelium of the urinary mucosa.

Bearberry’saquaretic action, i.e. its ability to increaserenal elimination of water, is attributed to thearbutoside, flavonoids and phenolic glucosides present in its leaves. In people suffering from fluid overload, bearberry promotes the elimination of sodium and potassium. Arbutoside, which is stable in the plant thanks to its tannins, is hydrolysed by the intestinal flora, releasinghydroquinone, a phenol which is then conjugated in the liver and excreted via the kidneys.

The plant also contains gall tannins, which have astringent properties. In high doses, these tannins can present a health risk. It also contains mucilage,arbutin and a glucoside that splits into hydroquinone and glucose under the action of certain ferments. In a basic environment, conducive to the development of bacteria responsible for cystitis, hydroquinone develops and destroys the germs, providing anti-infectious properties.

In association with heather or callune leaves, in the form of a decoction, bearberry leaves reinforce their antibacterial properties.

Bearberry leaves have an anti-inflammatory and antiseptic action on the urinary tract, and are used to prevent recurrent cystitis,prostate hypertrophy, urinary retention, urethritis, nephritis, urinary incontinence, diarrhoea, menorrhagia, leucorrhoea and other urinary or gynaecological disorders.

Are there any precautions to be taken when using Bearberry?

As hydroquinone requires alkaline urine to be produced and exert its antiseptic action, it is necessary when using bearberry to ensure that the urine pH is alkaline (measured by dipstick) or to alkalinise the urine by simultaneously adding sodium bicarbonate; either mineral waters such as St Yorre (4368 mg/L), Vichy Célestins (2989 mg/L) and Badoit (1300 mg/L), or sodium bicarbonate, or citrates (of sodium, potassium, magnesium), or via a diet rich in fruit and vegetables. It is advisable to drink plenty of water during treatment (at least two litres a day).

Contraindications:

• The EMA does not recommend bearberry for pregnant or breast-feeding women due to its oxytocic, uterostimulant and teratogenic properties.
• Bearberry is also contraindicated in cases of urinary tract cancer and kidney disease.
• According to the European agency, it is not recommended for children and adolescents for traditional use. Urinary tract infections in children and adolescents, even at an early stage, should be treated under medical supervision.

Precautions for use :

• Bearberry extracts are used in discontinuous cures of limited duration.
• The German Commission E recommends that bearberry should not be taken for more than one week or more than 5 times a year without medical advice.
• According to the EMA, the use of bearberry in men goes beyond its traditional use, which is recommended for women only.
• In the event of overdose, anorexia, nausea, vomiting, headache, irritability, insomnia, increased heart rate and albuminuria may occur.

Drug interactions :

• Bearberry may potentiate the gastrointestinal toxicity of synthetic non-steroidal anti-inflammatory drugs.
• Avoid taking substances that acidify the urine (medicines, vitamin C, cranberry, acidic fruit juices such as citrus fruit or prunes).
• Aqueous and methanolic extracts of 5 uva-ursi products showed strong inhibition of the cytochrome p450 isoenzyme.

How should Bearberry be taken and at what dosage?

Bearberry is a medicinal plant commonly used in phytotherapy for its antiseptic and diuretic properties. However, it’s important to know how to take bearberry and at what dosage to get the most out of it. In this section, we’ll look at the different ways to take bearberry and the recommended dosages for different types of condition.

Dry form :

• As a dietary supplement: in the form of dry extract or powder, in capsules.
• In the case of urinary tract infections, heather capsules can be taken in combination with this, at a rate of 1 capsule 3 times a day.

Liquid form :

• Standardised fluid extract of fresh plant: 5 to 10 ml per day in a glass of water, preferably in the morning.
• Herbal teas: 10 to 15 g of leaves per litre of water (after boiling, leave to simmer for 30 mins), 1 to 2 g per cup, to be drunk 3 to 4 times a day. To avoid gastric irritation due to the high tannin content, mint leaves can be added.