Hemp-nettle (Galeopsis tetrahit) is an annual plant widespread throughout the world, mainly in Europe and northern Asia. Hemp-nettle is controlled as a weed in flax, corn and root crops. Due to the high content of essential oils, hemp-nettle is strongly aromatic, which attracts pollinating insects and is beneficial to bees.
Currently, hemp-nettle is not a very popular medicinal herb, but until the mid-20th century it was used in the case of tuberculosis and various respiratory infections, as a means of facilitating expectoration.
The stem of hemp-nettle is erect, stiff, branched, growing up to 1 m high. In cross-section, it is clearly quadrangular, covered with quite long and rough to the touch hairs.
Thickenings appear in the place of nodes. Leaves growing opposite, on quite long petioles, large, ovate, pointed at the end, with serrated edges. Like the stem, covered with bristles. Flowers gathered in inflorescences in the form of pseudo-whorls.
Individual flowers have a labial, elongated corolla, occurring in various colours, most often from pink to purple, less often white or yellow. The petals of the corolla are also slightly hairy.
A yellow spot is visible inside the corolla. The calyx is hairy and prickly. The fruit is schizocarps gathered in round schizocarps. The root is small, taproot, with lateral radicles.
Hemp-nettle is quite easy to confuse with other plants from the Lamiaceae family, e.g. purple deadnettle, woodwort, etc. None of these plants are poisonous, and hemp-nettle stands out among them with rough, almost prickly hairs and the presence of a yellow spot in the centre of the corolla, as well as a veined pattern visible on approximately 2/3 of the surface of the lower lip.
Shoots, flowers, leaves.
In ancient natural medicine, hemp-nettle was used on a large scale, mainly for people with tuberculosis, atherosclerosis, diseases of the digestive tract and uric acid stones.
Currently, it is a plant that is not very popular and is rarely used for medicinal purposes. However, in specialist herbal shops, you can find the dried herb of hemp-nettle, which is intended for use in health problems such as:
Hemp-nettle has expectorant, coating and anti-inflammatory properties, hence it is used in the treatment of respiratory diseases, including pneumonia, bronchitis and laryngitis, flu, colds and even tuberculosis. Hemp-nettle prevents effusions and scarring of the bronchi, lungs and bronchioles. When taken for a long time, it limits the development of mycobacteria.
Hemp-nettle is known for its antispasmodic, slightly analgesic, antiseptic and antibacterial effects. It strengthens the walls of blood vessels, as a result of which it prevents the occurrence of internal effusions.
The herb is recommended for atherosclerosis. It helps maintain a normal level of blood pressure. The plant strengthens the body's general immunity, which reduces the risk of developing infections.
Hemp-nettle supports convalescence after long illnesses and regeneration of diseased organs. The infusion is used for migraines and relieves the symptoms of rheumatism.
Hemp-nettle has a beneficial effect on the urinary and excretory systems. It protects the urinary tract from the precipitation and deposition and supports the treatment of kidney stones.
It is recommended for inflammation of the digestive tract. The plant regulates the digestive process, increases the secretion of bile, and relieves flatulence. Infusions are used to make compresses that soothe bruises, swelling and wounds that are difficult to heal.
Due to the silica content, it has a good effect on the condition of bones and joints. Additionally, hemp-nettle improves the appearance of the skin, hair and nails.
It makes the skin more elastic and prevents excessive sebum secretion. It should be emphasized that the silica is soluble in water, which is why it is well absorbed in the digestive tract.
Preparations of the herb are used as an aid, without neglecting the routine procedure indicated by the doctor, in the case of inflammation of the mucous membranes of the digestive system, skin damage, in post-operative conditions, with increased permeability of the capillary walls of blood vessels or even burns.
This plant is also used to supplement the deficiency of mineral components, especially in convalescents and the elderly.
For a long time, in folk medicine, hemp-nettle has been used as a sedative, helping to fight long-term stress and problems with falling asleep. Infusions of the herb were and still are an astringent, anti-inflammatory and analgesic, bringing relief in migraines.
The herb is also recommended in the case of atherosclerosis and hypertension. Hemp-nettle strengthens the general, natural immunity of the body, which reduces the risk of developing various infections.
In the 19th and until the mid-20th century, the herb was used for pneumonia and bronchitis, tuberculosis and persistent and long-lasting cough, because the saponins contained in it dilute the thick, accumulated mucus and purulent secretions in the respiratory tract and facilitate expectoration. They also support the healing process of lung tissue and reduce pulmonary effusion.
Saponins, thanks to their antiseptic effect, inhibit the development of bacterial diseases in the throat, such as sore throat. Due to the presence of silica, the herb increases the scarring of tuberculosis lesions, and its long-term use limits the development of mycobacteria, i.e. the bacteria that cause this contagious disease.
Hemp-nettle has a positive effect on the digestive system, by improving the digestion process, as it increases the secretion of bile and stimulates the work of the intestines. Moreover, the saponins present in the plant inhibit the growth of bacteria and fungi in the digestive tract.
Hemp-nettle is increasingly used as a diuretic, but always in combination with other raw materials that act on the urinary tract. Hemp-nettle has a beneficial effect on the urinary system, as it hinders the precipitation of urinary deposits and supports diuresis, i.e. all phenomena related to the process of excretion of urine.
In homeopathy, hemp-nettle is recommended for bladder and kidney ailments, such as, among others, urolithiasis.
The infusion and decoction of the herb should be used by people struggling with acne and sagging skin. The silica contained in the herb improves skin elasticity, and the polyphenols narrow enlarged pores and inhibit excessive sebum secretion.
The infusion of hemp-nettle applied to the skin has anti-inflammatory and antiseptic properties, which is why it is recommended for people struggling with acne.
Hemp-nettle, like couch grass or bedstraw, is a good source of skin-absorbable silica, which strengthens and seals blood vessels and has a beneficial effect on joints and connective tissue proper.
Hemp-nettle stimulates the regeneration and healing of the epidermis, and also stabilizes the structure of collagen fibers, which helps to rejuvenate the skin and reduce the visibility of wrinkles.
This species prefers primarily humus, fertile, moderately moist, limestone soils rich in nutrients, mainly nitrogen, but can also develop in other locations.
Hemp-nettle is a shade-loving species, which is why it rarely occurs in places with strong sunlight. In nature, it can most often be found on wastelands, field edges, open, forest clearings, ruderal sites and roadsides. On cultivated land, however, it appears mainly in spring cereals, such as spring wheat, oats, spring barley and orchards.
Hemp-nettle is a good source of soluble and easily digestible silica, iridoids, flavonoids and terpenoids. It also contains saponins, tannins, organic acids (phenolic): salicylic, caffeic, cinnamic, essential oils, bitter substances, mineral salts.
Hemp-nettle is intended mainly for internal, oral use. The most popular form of its administration is home-made infusions and decoctions. The optimal portion of the infusion is considered to be 1 glass per day.
However, the maximum safe dose of the herb has not been determined to date, therefore it is not recommended to exceed the above amounts.
When taking any preparations containing the herb or extracts from this plant, the manufacturer's recommendations should be strictly followed.
There are also no known interactions between hemp-nettle and medications, supplements or other herbs. Therefore, when taking any other preparations, great caution and consultation with a doctor is recommended.
Hemp-nettle should not be consumed by pregnant women, breastfeeding women and children due to the lack of scientific data confirming the full safety and benefits of its consumption in the above groups.
To prepare a homemade infusion of hemp-nettle, simply pour 1 tablespoon of the dried herb with half a glass of hot water, leave covered for 10 minutes, strain and drink (1 glass per day).
Pour 1 tablespoon of the herb with 1 glass of water, leave overnight and boil covered in the morning for about 10 minutes. It is assumed that such a decoction of hemp-nettle can be drunk up to 3 times a day, approximately ½ glass per portion.
Pour 4 parts of 40-60% alcohol over 1 part of the dry, crushed raw material. For example, 400 ml of alcohol is needed for 100 g of herb. The mixture is left in a glass container in a cool and dark place for about 14 days. During this time, maceration occurs. Then it is filtered and poured into bottles. The recommended daily intake is 1 x 10 ml.
For this purpose, pour 1.5 l of water over 50g of the herb and put on low heat. After bringing to a boil, cook covered for 10 minutes. Finally, strain and add to a bathtub with water at a temperature of about 37°C. The bath time should be an average of 20 minutes.
It is possible to consume hemp-nettle ground into powder, which is washed down with a glass of water. The recommended daily intake is 2 times 0.5 - 1 g (¼–½ teaspoon).
The flowering herb is collected from June to October. The plant can be prickly and unpleasant to the touch, so it is best to use gloves. The upper shoots with flowers and one or two pairs of leaves are collected.
Dry the loosely spread material in a dark (due to the content of iridoids), airy place, at a temperature of up to 35°C.
After drying, the raw material should be stored in a tightly closed jar or paper bag, away from the sun, for example in a kitchen cupboard. The shelf life is 1 year, after this time the essential oils lose their properties and the herbs must be thrown away.
