Alfalfa (Medicago Sativa) Family: Legume
- Buffalo herb
- Purple medic
Habitat: North America, the
Mediterranean region, western Asia; foothills and mountain areas.
Description: A perennial plant with
a smooth, erect stem that grows 2 to 3 feet tall. It bears grayish-green
pinnately trifoliate leaves, with egg-shaped leaflets; it looks much like a
large clover. Its violet-purple flowers grow in racemes from June to August,
producing spirally-coiled seed pods.
Medicinal Parts: Dried whole herb, including
blossoms; gathered at the beginning of flowering seasons.
* For definition of some of the above terms
see the dictionary section of this book
Alfalfa has been extensively studied. Whole
plant material contains many important substances, including several saponins,
many sterols, flavonoids, coumarins, alkaloids, acids, vitamins, amino acids,
sugars, proteins (25% by weight), minerals, trace elements, and other
nutrients. Whole alfalfa also contains plenty of fiber with anticholesterolemic
Alfalfa is one of the most nutritious foods
known. Its calcium, chlorophyll, carotene, and vitamin K content make alfalfa
an important nutritional supplement. Alfalfa root saponins can inhibit
increases in blood cholesterol levels by 25% in experimental animals fed a high
cholesterol diet. Offsetting this positive effect are findings that the root is
hemolytic and may interfere with vitamin E metabolism.
The high concentration of vitamin K found in whole alfalfa
has beneficial effect on several forms of hemolytic disease. Alfalfas also has
antibacterial and antitumoral properties. In folk medicine, the herb has been
used as an appetizer and tonic, and as a diuretic to relieve urinary and bowel
Perhaps the most common modern use of alfalfas is in the
treatment of symptomatic arthritis, but although numerous clinical and
anecdotal reports are available, no scientific research has been done on it
METHOD OF ACTION
Alfalfa contains vitamin K, an
Vitamin K is found in many green leafy
plants, but is especially abundant in alfalfa. The herb has therefore been
effectively used in treatment of vitamin K disorders in man. When the delivery
of bile to the bowel is hindered, as in obstructive jaundice or biliary
fistula, a bleeding disorder may arise. Other bleeding disorders may result
from the use of artificial formulas to feed newborns, protracted antibiotic
therapy, pancreatic insufficiency, chronic diarrhea and steatorrhea, and from
the misuse of anticoagulants, aspirin, and anticonvulsant drugs
Alfalfa has antibiotic
The saponins in alfalfa have been shown to be
antifungal. This activity is concentrated mainly in the medicagenic acid
fraction. Alfalfa has shown some activity against tuberculosis bacteria, while
aqueous and volatile extracts of alfalfa are antibacterial against gram
Alfalfa has antitumor action
Basic proteins (histones) displaying
antitumor activity without undesired side effects occur in alfalfa. These
substances contain high levels of l-lysine, aspartic acid, and glutamic acid.
Tumor stimulating fractions were also found, containing large amount of
l-arginine. This basic relationship requires further study.
Other pharmacology of alfalfa
Tricin has been isolated from alfalfa and
found to cause smooth muscle relaxation in guinea pig intestinal tissue, and to
have some slight estrogenic property.
Alfalfa is highly nutritious
The nutrient content of alfalfa is one of the
richest known, making it a useful livestock fodder and a highly recommended
herb for the human diet as well.
Alfalfa root pharmacology
The hypocholesterolemic effect of alfalfa
root saponins has been thoroughly established. Alfalfa root saponins can
inhibit increases in blood cholesterol levels by 25% in experimental animals
fed a high cholesterol diet.
Method of action
Alfalfa root saponins also have a hemolytic
effect. It appears that this hemolytic effect is the result of a marked
reduction in prothrombin factor concentration. In addition, they may interfere
with the metabolism of vitamin E.
Alfalfa's hypoprothrombonemic effect may be
increased by the antiarrhythmic agent, quinidine. In addition, allopurinol has
been tentatively shown to increase the half-life of anticoagulants.
Alfalfa is high in iron, which may cause it
to interfere with the absorption of tetracyclines. This is especially true if
large quantities of herb are ingested with two hours of taking
It should also be noted that animal studies
indicate that iron plus allopurinol may lead to increased hepatic iron
Alfalfa may, because of the presence of
eugenol in the herb, inhibit certain liver microsomal hydroxylating systems.
This produces toxic effects from drugs normally metabolized by those
It should be noted that while the coumarin content of
alfalfa is not high at normal usage levels, coumarins can affect the action of
almost any drug.
The presence of tyramine and/or tryptophan in
alfalfa could produce hypertension if monoamine oxidase inhibitors (MAOI's) are
also being used. However, this is not a likely interaction.
General Herb Reference Collection: The
following general reference books contain information about specific drug
interactions as well as interactions between classes of drugs. This herb's
possible interactions may be adduced by consulting the chapter on that class in
the following volumes, since the herb resembles the class indicated.
Mowrey, D.B., Ph.D. Experimental Psychology,
Brigham Young U. Director of Nebo Institute of Herbal Sciences. Director of
Behavior Change Agent Training Institute. Director of Research, Nova Corp.
American Hospital Formulary Service. American
Society of Hospital Pharmacists. Washington, D.C.
Goodman, L.S. & A. Gilman. 1975. The
Pharmacological Basis of Therapeutics. Macmillan, New York.
Hansten, P.D. 1979. Drug Interactions, 4th
ed. Lea & Febiger, Philadelphia.
List, P.H. & L. Hoerhammer. 1969-1976.
Hagers Hanbuch der Pharmazeutischen Praxis, vols. 2-5. Springer-Verlag,
Bressler, R., M.D. Bogdonoff & G.J.
Subak-Sharpe. 1981. The Physicians Drug Manual. Doubleday & Co., Inc.
Garden City, New York. 1213 pp.
Kastrup, E.K., ed. 1981. Drug Facts and
Comparisons, 1982 edition. Facts and Comparisons Division, J.P. Lippincott Co.,
Philadelphia (St. Louis).
Marx, A.V. & Adler, E. "Ueber die
blutzuckerherbasetzende wirkung von herba, urticae dioicae." Naunyn-Schmied.
Arch. Parmakol., 112, 29-38, 56, 1926.
Generally regarded as safe by the FDA.
Contact dermatitis has occurred in
hypersensitive individuals. Alfalfa root saponins are hemolytic and may also
interfere with the metabolism of vitamin E; however, above-ground parts have
just the opposite effects.
The toxic effects of alfalfa root saponins
have been shown to be counteracted by cholesterol and beta sitosterol.