Natural Products

Aloe

Aloe vera

Efficacy

• Indications with proven efficacy:
  Constipation
• Indications with possible, but poorly documented efficacy - the use of this product cannot be recommended:
  Psoriasis
  To heal burns and other superficial wounds
• Also used for these other indications, but with no proof of efficacy:
  Amenorrhea
  Asthma
  Cold
  Colitis
  Depression
  Diabetes
  Epilepsy
  Glaucoma
  Hemorrhoids
  Human immuno-deficiency virus (HIV) treatment
  Kidney stones prevention
  Multiple sclerosis
  Peptic ulcers

Security

• Risk of Drug Interactions: Moderate
• Adverse Effects: Frequent

What is it?

Aloe is a tropical plant with thick triangular leafs that resemble spines. According to ancient documents, its medicinal value has been known for centuries. It was probably first used in Egypt or the Middle-East. Since then, aloe has been introduced to most warm tropical areas of the world, including Southern United-States, South America, Mexico, the Caribbean and India.

People use the aloe latex (sap), which contains aloin as its main principle, as a laxative. This plant also contains a gel, which is used topically. Aloe latex and gel do not contain the same active principles and should not be confused.

Warning

In 2004, Canada adopted new regulations that control the manufacturing, packaging, labeling and importing of natural health products. The new regulations also include an adverse reaction reporting system. Products that conform to the regulation's criteria are identified with a natural product number (NPN) or homeopathic medicine number (DIN-HM) and can be legally sold in Canada. This number indicates that the product meets specific criteria for safety and purity, not that it is effective for any indication.

Medicinal plants content varies naturally from plant to plant – just as fruits from the same package may vary in taste and texture. There is no standard to measure the active content of each plant. Thus, efficacy of natural products should be expected to vary from brand to brand as well as from bottle to bottle of the same brand.

For more information about the Natural Health Products Regulations, or to check if a product has been assessed, visit the Health Canada website at http://www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php.

Does it work?

Aloe's efficacy as an oral laxative has been established. Topical application of aloe gel appears to promote healing. The gel is also used to reduce inflammation and pain associated with burns, skin ulcerations, dermabrasions, psoriasis and frostbite injury.

• Constipation:
  Aloe sap is a potent laxative. The usual laxative dose is 100 to 200 mg of aloe or 50 mg of aloe extract, once a day in the evening.
• Wounds (topical application):
  Aloe gel, in strengths varying from 98 to 100%, might effectively promote the healing process when applied to wounds. It is applied liberally 3 to 5 times a day, as needed. The use of the gel directly from a broken leaf is preferable.

There is insufficient reliable information to conclude that aloe is effective in any other indication.

Is it safe?

• When recommended doses are used over short periods, aloe appears to be safe and effective. It can sometimes induce intestinal cramps. In such cases, the dose should be reduced.
• Aloe should not be used frequently and over long periods as a laxative, since it may lose some of its efficacy and cause a loss of electrolytes, especially potassium. This loss could be problematic, especially in people with heart disease. Aloe should not be used in people with an inflammatory intestinal disorder, nausea, vomiting, hemorrhoids, or in presence of kidney disorders. It is contraindicated in children less than 12 years of age.
• No specific toxicity has been associated with the use of the topical gel. However, some people are allergic to aloe sap.
• Oral aloe is contraindicated during pregnancy, since the product may induce a spontaneous abortion and menstruation. Because aloe is excreted in breast-milk, women should not take aloe while breast-feeding.
• People who take digoxin (Lanoxintm, an antiarrhythmic drug), diuretics or corticosteroids appear to be at an increased risk for adverse reactions. Before taking aloe, check with your pharmacist to make sure that there are no interactions with your regular medication.

Clinical notes

• Aloe juice (latex) is a potent stimulant laxative. Even though its efficacy is well-documented, it should be used only on an occasional basis, over a few days.

References

1. Blumethal M et al. The Complete German Commission E monographs, 1998
2. Natural Medicines Comprehensive Database, Therapeutic Research Faculty, 2007
3. Lininger S. et Al. The Natural Pharmacy, Prima Health, 1998
4. Pierce Andrea, Practical Guide to Natural Medicines, 1999
5. Passeportsanté.net. Aloès. http://www.passeportsante.net
6. Barnes J. et Al. Herbal Medicines, 2nd edition, Pharmaceutical Press, 2002
7. Herbal Companion to AHFS DI, American Society of Health-System Pharmacists, 2001