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Alfalfa

Alfalfa

What is it?

Alfalfa is an herb. People use the leaves, sprouts, and seeds to make medicine.

Alfalfa is used for kidney conditions, bladder and prostate conditions, and to increase urine flow. It is also used for high cholesterol, asthma, osteoarthritis, rheumatoid arthritis, diabetes, upset stomach, and a bleeding disorder called thrombocytopenic purpura. People also take alfalfa as a source of vitamins A, C, E, and K4; and minerals calcium, potassium, phosphorous, and iron.

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for ALFALFA are as follows:

Insufficient evidence to rate effectiveness for…

  • High cholesterol. Taking alfalfa seeds seems to lower total cholesterol and “bad” low-density lipoprotein (LDL) cholesterol in people with high cholesterol levels.
  • Kidney problems.
  • Bladder problems.
  • Prostate problems.
  • Asthma.
  • Arthritis.
  • Diabetes.
  • Upset stomach.
  • Other conditions.

More evidence is needed to rate alfalfa for these uses.

How does it work?

Alfalfa seems to prevent cholesterol absorption in the gut.

Are there safety concerns?

Alfalfa leaves are POSSIBLY SAFE for most adults. However, taking alfalfa seeds long-term is LIKELY UNSAFE. Alfalfa seed products may cause reactions that are similar to the autoimmune disease called lupus erythematosus.

Alfalfa might also cause some people’s skin to become extra sensitive to the sun. Wear sunblock outside, especially if you are light-skinned.

Special precautions & warnings:

Pregnancy or breast-feeding: Using alfalfa in amounts larger than what is commonly found in food is POSSIBLY UNSAFE during pregnancy and breast-feeding. There is some evidence that alfalfa may act like estrogen, and this might affect the pregnancy.

“Auto-immune diseases” such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), rheumatoid arthritis (RA), or other conditions: Alfalfa might cause the immune system to become more active, and this could increase the symptoms of auto-immune diseases. There are two case reports of SLE patients experiencing disease flare after taking alfalfa seed products long-term. If you have an auto-immune condition, it’s best to avoid using alfalfa until more is known.

Hormone-sensitive condition such as breast cancer, uterine cancer, ovarian cancer, endometriosis, or uterine fibroids: Alfalfa might have the same effects as the female hormone estrogen. If you have any condition that might be made worse by exposure to estrogen, don’t use alfalfa.

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Diabetes: Alfalfa might lower blood sugar levels. If you have diabetes and take alfalfa, monitor your blood sugar levels closely.

Kidney transplant: There is one report of a kidney transplant rejection following the three-month use of a supplement that contained alfalfa and black cohosh. This outcome is more likely due to alfalfa than black cohosh. There is some evidence that alfalfa can boost the immune system and this might make the anti-rejection drug cyclosporine less effective.

Are there interactions with medications?

Major
Do not take this combination.
Warfarin (Coumadin)
Alfalfa contains large amounts of vitamin K. Vitamin K is used by the body to help blood clot. Warfarin (Coumadin) is used to slow blood clotting. By helping the blood clot, alfalfa might decrease the effectiveness of warfarin (Coumadin). Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.
Moderate
Be cautious with this combination.
Birth control pills (Contraceptive drugs)
Some birth control pills contain estrogen. Alfalfa might have some of the same effects as estrogen. However, alfalfa is not as strong as the estrogen in birth control pills. Taking alfalfa along with birth control pills might decrease the effectiveness of birth control pills. If you take birth control pills along with alfalfa, use an additional form of birth control such as a condom.

Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.

Estrogens
Large amounts of alfalfa might have some of the same effects as estrogen. However even large amounts of alfalfa are not as strong as estrogen pills. Taking alfalfa along with estrogen pills might decrease the effects of estrogen pills.

Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others.

Medications for diabetes (Antidiabetes drugs)
Alfalfa might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking alfalfa along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), and others.

Medications that decrease the immune system (Immunosuppressants)
Alfalfa might increase the immune system. By increasing the immune system, alfalfa might decrease the effectiveness of medications that decrease the immune system.

Some medications that decrease the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and others.

Medications that increase sensitivity to sunlight (Photosensitizing drugs)
Some medications can increase sensitivity to sunlight. Large doses of alfalfa might also increase your sensitivity to sunlight. Taking alfalfa along with medication that increase sensitivity to sunlight could make you even more sensitive to sunlight, increasing the chances of sunburn, blistering or rashes on areas of skin exposed to sunlight. Be sure to wear sunblock and protective clothing when spending time in the sun.

Some drugs that cause photosensitivity include amitriptyline (Elavil), Ciprofloxacin (Cipro), norfloxacin (Noroxin), lomefloxacin (Maxaquin), ofloxacin (Floxin), levofloxacin (Levaquin), sparfloxacin (Zagam), gatifloxacin (Tequin), moxifloxacin (Avelox), trimethoprim/sulfamethoxazole (Septra), tetracycline, methoxsalen (8-methoxypsoralen, 8-MOP, Oxsoralen), and Trioxsalen (Trisoralen).

Are there interactions with herbs and supplements?

Herbs and supplements that might lower blood sugar
Alfalfa might lower blood sugar. Using alfalfa along with other herbs and supplements that might lower blood sugar might lower blood sugar too much. Herbs that might lower blood sugar include devil’s claw, fenugreek, guar gum, Panax ginseng, and Siberian ginseng.
Iron
Alfalfa might lower the body’s absorption of dietary iron.
Vitamin E
Alfalfa might interfere with the way the body takes in and uses vitamin E.

Are there interactions with foods?

There are no known interactions with foods.

What dose is used?

The following doses have been studied in scientific research:

BY MOUTH:

  • For high cholesterol: a typical dose is 5-10 grams of the herb, or as a steeped strained tea, three times a day. 5-10 mL of a liquid extract (1:1 in 25% alcohol) three times a day has also been used.

Other names

Feuille de Luzerne, Grand Trèfle, Herbe aux Bisons, Herbe à Vaches, Lucerne, Luzerne, Medicago, Medicago sativa, Phyoestrogen, Phyto-œstrogène, Purple Medick, Sanfoin.

Methodology

To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.

References

  1. Mac Lean JA. Unsaponifiable substance from alfalfa for pharmaceutical and cosmetic use. Pharmaceuticals 1974;81:339.
  2. Malinow MR, McLaughlin P, Naito HK, and et al. Regression of atherosclerosis during cholesterol feeding in
  3. Ponka A, Andersson Y, Siitonen A, and et al. Salmonella in alfalfa sprouts. Lancet 1995;345:462-463.
  4. Kaufman W. Alfalfa seed dermatitis. JAMA 1954;155:1058-1059.
  5. Rubenstein AH, Levin NW, and Elliott GA. Manganese-induced hypoglycemia. Lancet 1962;1348-1351.
  6. Van Beneden, C. A., Keene, W. E., Strang, R. A., Werker, D. H., King, A. S., Mahon, B., Hedberg, K., Bell, A., Kelly, M. T., Balan, V. K., Mac Kenzie, W. R., and Fleming, D. Multinational outbreak of Salmonella enterica serotype Newport infections due to contaminated alfalfa sprouts. JAMA 1-13-1999;281:158-162. View abstract.
  7. Malinow, M. R., McLaughlin, P., Naito, H. K., Lewis, L. A., and McNulty, W. P. Effect of alfalfa meal on shrinkage (regression) of atherosclerotic plaques during cholesterol feeding in monkeys. Atherosclerosis 1978;30:27-43. View abstract.
  8. Gray, A. M. and Flatt, P. R. Pancreatic and extra-pancreatic effects of the traditional anti- diabetic plant, Medicago sativa (lucerne). Br J Nutr. 1997;78:325-334. View abstract.
  9. Mahon, B. E., Ponka, A., Hall, W. N., Komatsu, K., Dietrich, S. E., Siitonen, A., Cage, G., Hayes, P. S., Lambert-Fair, M. A., Bean, N. H., Griffin, P. M., and Slutsker, L. An international outbreak of Salmonella infections caused by alfalfa sprouts grown from contaminated seeds. J Infect.Dis 1997;175:876-882. View abstract.
  10. Jurzysta, M. and Waller, G. R. Antifungal and hemolytic activity of aerial parts of alfalfa (Medicago) species in relation to saponin composition. Adv.Exp Med Biol 1996;404:565-574. View abstract.

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Last reviewed – 02/12/2015
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This copyrighted, evidence-based medicine resource is provided by Natural Medicines Comprehensive Database Consumer Version. Natural Medicines Comprehensive Database disclaims any responsibility related to consequences of using any product. This monograph should not replace advice from a healthcare professional and should not be used for the diagnosis or treatment of any medical condition.