Botanical name: 

The ripe seeds of Linum usitatissimum, Linné (Nat. Ord. Linaceae). Levant and southern Europe; cultivated.
Common Names: Flaxseed, Linseed.

Principal Constituents.—Mucilage, a fixed, viscid oil (Oleum Lini), proteids (25 per cent), and a minute trace of amygdalin.
Preparations.—1. Oleum Lini, Linseed Oil, (Oil of Flaxseed, Raw Lipseed Oil). A yellowish oil of a bland taste and peculiar odor, gradually thickening and darkening in the air and acquiring a strong taste and odor. Dose, ½ to 1 fluidounce. Raw (not boiled) oil only should be used.
2. Farina Lini, Linseed Meal, (Flaxseed Meal). For poultices.

Action and Therapy.—External. Flaxseed and its oil are emollient. A flaxseed poultice (Cataplasma Lini) applied early upon inflamed and painful surfaces will relieve pain, cause relaxation, and sometimes resolution. If applied after pus begins to form it will hasten suppuration. Deepseated inflammation can often be aborted by the judicious use of a flaxseed poultice. The danger of favoring sepsis when used upon open or abraded tissues should be borne in mind. Equal parts of linseed oil and lime water form Carron Oil, the best primary dressing for burns and scalds. Linseed meal added to the wash water will assist in removing the odor of iodoform from the hands.

Internal. An infusion of the seeds (½ ounce to Boiling Water, 16 fluidounces) is an excellent demulcent forming a pleasant mucilaginous drink for inflamed or irritated membranes. It is especially useful in gastro-intestinal and renal inflammations, and as a lenitive after acute poisoning by irritants. The addition of licorice root or lemon juice and sugar makes of the foregoing an agreeable linctus for irritative coughs and acutely inflamed bronchial mucous membranes. Linseed oil is a good laxative and is sometimes used as an enema to remove ascarides. Hemorrhoids have been cured by the laxative influence of linseed oil given in daily repeated doses of 1 to 2 ounces. Linseed oil may be given freely in poisoning by alkalies, when other bland oils are not at hand.

The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.