Bilberry
Botanical name
Bilberry, Blueberry, Whortleberry, Huckleberry - Vaccinium myrtillus L.
Family
Heath family (Ericaceae)
Information about the plant
The Bilberry grows as undergrowth in light pine and spruce forests, and on the moors in central and northern Europe, Asia and North America, rising in the south to the alpine level. It plays an important role among the native wild fruit berries, but today it is barely collected in the wild for the commercial food industry, possibly even in Austria and the Balkans. Bilberries for pharmaceutical purposes originate almost exclusively from wild resources. The ripe berries are separated by a special combing of the plant, then either dried or frozen immediately and preserved.
The genus name Vaccinium is derived from the Latin "bacca" (= berry) and "baccinium" (= berry shrub), which is also used for the cranberry (V. vitis-idea), the bog bilberry (V. uliginosum) and fenberry (V. oxycoccus is used). The epithet myrtillus also has Latin roots and is derived from "myrtus" (= myrtle) and refers to the fact that the leaves of the Bilberry are similar to the Myrtle. In fact they are so leathery like the Myrtle, but smaller, thus forming the diminutive of Myrtillus. The Bilberry is a deciduous dwarf shrub 20 to 50cm high with sharp-edged branches that have ovate, very short petiolate leaves with finely serrated edges. The pale red to green bell-like flowers are in the leaf axils. The fruits are spherical, blue-black, frosted white, very juicy and sweet.
Medicinally used parts of plants (herbal drug)
The ripe fruit is used, both in the dried state as well as fresh berries, and dried leaves. The drugs are mainly from South-East Europe, also from Italy and the USA.
Constituents of the herbal drug
Bilberry fruits contain anthocyanins, the dried fruits also have catechin tannins and invert sugar. Bilberry leaves contain catechin tannins, flavonoids, phenolic acids and iridoids.
Quality of the drug
The quality of the following drugs or drug preparations is specified in the European Pharmacopoeia (Ph. Eur.):
- dried Bilberries (Myrtilli siccus fructus)
- fresh Bilberries (Myrtilli recens fructus)
- preset, purified dried extract from fresh Bilberries (Myrtilli fructus recentis extractum siccum raffinatum et normatum)
Medical applications
Recognised medical use
Bilberry fruit
Dried Bilberries: for non-specific, acute diarrhoeal diseases (Commission E, ESCOP); Commission E also recommends external use for the treatment for mild inflammation of the mouth and throat. Caution: fresh Bilberries have a slightly laxative effect!
Fresh Bilberries: They are used exclusively for the production of anthocyanin-rich extracts in finished pharmaceutical products and processed for the prevention of night blindness and improved night vision.
Bilberry leaves
The Commission E has awarded the bilberry leaves an unfavourable risk-benefit ratio (negative monograph), therapeutic use is not recommended. Because of their astringent effect (tannin drug) Bilberry leaves can be used short-term internally in the form of a tea infusion for mild diarrhoea, and they are used externally for rinses and washes (popular usage). Caution is advised with declarations such as "Sugar tea" or "anti-diabetic tea" and "to lower blood pressure," which is sometimes how Bilberry leaves are advertised and offered in alternative markets.
Traditional use
Bilberry fruit and Bilberry leaves have no listing as traditional medicines (§ 109a). Extracts and anthocyanins from fresh Bilberry fruit are traditionally used for the prevention of night blindness (registration).
Herbal drug preparations in finished dosage forms
- dried blueberries for decoctions
- anthocyanins from Bilberry fruit in pills
- cut leaf herb for making tea
Dosage
Prepared drugs: see package insert;
Tea infusion: drink 1 cup freshly prepared dried bilberry fruit drink several times a day (bilberry fruit tea); daily dose of 20 to 60g of the drug. Children can chew 10 grams of dried berries several times daily or put the berries previously soaked in water in their porridge.
To improve night vision it is recommended to just take the finished medicinal product with standardised extracts (single doses of 100mg anthocyanins).
Bilberry leaves: for diarrhoea drink 1 cup of bilberry leaf tea 3-4 times a day.
Preparation of a tea
Dried bilberry fruit: 5 to 10g of crushed bilberry fruit is mixed with 150ml of cold water, the mixture is brought to the boil and removed from the heat after 10 minutes and strained.
Bilberry leaves 1 to 2.5g of finely chopped bilberry leaves are mixed with 150ml of boiling water and strained after 5 to 10 min.
Notes
Bilberry fruit
If diarrhoea persists for 3 to 4 days, a visit to the doctor is recommended. There are still no studies on its harmlessness for use with children under 4 years old.
Bilberry leaves
Poisoning can occur with the prolonged ingestion of bilberry leaves, so a dose is not recommended (see also "recognised medical impact" - Negative monograph of the Commission E).
Side effects
None known.
Interactions
None known.
References
Herbal drug monographs
Further literature
Wichtl: Teedrogen und Phytopharmaka, pg. 456 and pg. 460
Schilcher: Leitfaden Phytotherapie, pg. 118
Van Wyk: Handbuch der Arzneipflanzen, pg. 333
Kommentar zum Europäischen Arzneibuch (Dried bilberried, no. 1588; Fresh bilberries, no. 1602; Dried extract from fresh bilberries, no. 2394)