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Botanical name

Linseed or Flax - Linum usitatissimum L.


Flaxes (Linaceae)

Useful information about the plant

Linseed is known as a cultivated plant. It comes in many different forms of culture and provides the linseed seeds, linseed oil and flax fibres. The main plant is closely allied to the Mediterranean growing Wildlein L. angustifolium Huds. Linseed grows practically all over the world except for the countries near the equator. It can also be grown at an altitude of up to 1800 metres. The harvest of linseed and flax fibres, however, is highly dependent on the climatic conditions.
The genus name is a direct translation from the Latin "linum" (= flax), usitatissimum is the superlative of the Latin word "usitatus" (= usual, customary) from the Latin "usus" (= use, benefits) and thus clearly reflects the great benefits of this plant.
Linseed is an annual plant, it is about 1m high and it is very tender due to its thin, narrow lanceolate, pointed leaves. The sky-blue 5-pointed flowers are arranged in a panicle in the leaf axils of the upper leaves. The fruit ripens to a 10-fold capsule with brown seeds. Depending on the species, the flowers are white and light blue or purple, flowering time is June/July.

Medicinally used plant parts (drug)

The ripe, light brown to reddish brown seeds are used. The drug comes from farms in Morocco, Argentina, Belgium, Hungary and India.

Ingredients of the drug

Linseed/Flaxseed contains mucilage in the seed coat, fatty oil in the endosperm with a high proportion of polyunsaturated fatty acids.

Descriptions of the quality

The quality of linseed/flaxseed (Lini semen) is specified in the European Pharmacopoeia (Ph. Eur.).

Medical Application

Recognised medical use

Internally for recurring constipation, damaged gut due to laxative abuse, irritable bowel syndrome and also in diverticulitis. As a mucus preparation in gastritis (stomach inflammation) and enteritis (intestinal inflammation). Externally as a hot poultice (cataplasm) with skin inflammation (Commission E, ESCOP).
The HMPC has accepted the internal use of flaxseed in recurrent constipation and softening of the stool as "well-established medicinal use". By contrast, the HMPC has classified flaxseed, which serves only as a mucus preparation, as a traditional herbal medicinal product (see also "traditional use").

Traditional use

Flaxseed has been categorised by the HMPC as a traditional herbal medicine (§ 39a AMG) for the mucus preparation. Based on a long tradition, linseed mucus may be used for the symptomatic relief of slight gastrointestinal discomfort.
Flaxseed is traditionally used to prevent constipation (traditional use acc. to § 109a).

Medicinal herbal preparations in finished drug products

  • whole or crushed linseed


For constipation take 1 tablespoon (10g) of uncrushed or crushed flaxseed 2 - to 3-times daily with plenty of liquid (!). Flax seed can be taken pre-swelled in water. During therapy with linseed it must be ensured in each case that there is a high fluid intake. To prepare put 5 to 10g of flaxseed in cold water for 20 to 30 min. Thereafter, the liquid is decanted. For external use as a compress, process 30 to 50g of ground flaxseed into a hot and humid pulp.


Linseed should not be used if there is a suspicion of intestinal obstruction (ileus) and narrowing of the oesophagus and the stomach-intestinal tract as well as in acute inflammatory bowel diseases and disorders of the oesophagus and cardia. Use in children under 12 years old is not recommended due to lack of experience.

Side effects

If the increased fluid intake is respected there are no side effects to be expected, at worst flatulence.


Linseed should be taken ? to 1 hour before or after taking other medicines, as otherwise it may delay the absorption of the other drugs in the gastro-intestinal tract.


Drug monographs

HMPC, Commission E, ESCOP

Further reading

Wichtl: Teedrogen und Phytopharmaka, pg. 392
Schilcher: Leitfaden Phytotherapie, pg. 163
Van Wyk: Handbuch der Arzneipflanzen, pg. 193
Kommentar zum Europäischen Arzneibuch (Linseed, no. 0095)

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