Bottom Line: Aloe is safe for topical use. It is not an effective cancer treatment and is dangerous when given by injection.
Scientists think that compounds found in aloe inhibit molecules that play a role in inflammation. Studies in laboratory rats confirm this anti-inflammatory activity. Aloe is also thought to hinder the formation of thromboxane, a molecule that is detrimental to the healing of burn wounds. Aloe kills bacteria and fungi directly in laboratory studies. Aloe vera gel should not be confused with aloe juice or aloe latex, both of which contain potent laxative substances.
As a topical anesthetic Laboratory evidence supports this use, but it has not been tested in clinical trials.
To treat burns Scientific evidence supports the topical use of aloe for minor burns.
To prevent and treat redness, rash, and pruritus caused by radiation therapy Clinical trials have produced conflicting results in support of and against this use. Topical use of aloe is generally safe.
As a skin moisturizer No scientific evidence supports this use.
To treat inflammation associated with conditions such as cold sores, eczema, and pruritis Clinical evidence supports this use.
To treat cancer No scientific evidence supports this use. Cancer therapy using injections of acemannan, a substance found in aloe, resulted in death of several patients.
To treat diabetes Two nonrandomized trials conducted by the same group suggest that blood glucose levels may be reduced by aloe vera. Further study is warranted.
To treat ulcerative colitis A small randomized, controlled trial shows weak support for this use. More research is needed.
Clinical evidence generally supports the topical use of aloe vera for minor burns, frostbite, wound healing and inflammation, especially when combined with hydrocortisone.
Prevention or treatment of radiation therapy-induced side effects A randomized, controlled trial compared 98% pure aloe vera gel to a placebo gel or nothing at all in 301 breast cancer patients receiving chest wall irradiation. Patients applied the gel twice daily, starting within three days of their first radiation treatment. Women in all three groups developed rashes and redness at the same rate, suggesting that aloe vera is not effective in treating or preventing radiation-induced skin problems. Another study compared the use of a mild soap with or without a topical aloe vera gel in 70 patients undergoing radiation therapy for cancer. The time it took for skin changes (such as redness and itching) to develop was measured, and practically no difference was seen between patients using aloe and those using soap alone. However, patients who used aloe and received high doses of radiation (greater than 2700 cGy) did show some benefit. It should be noted that the aloe vera gel also included vitamin E and other ingredients that may have had an effect on patients' skin outcomes. In a recent clinical trial, 225 women with breast cancer who received radiation therapy after lumpectomy or partial mastectomy were studied to see if aloe vera gel was better than a water-based body cream in preventing skin side effects of radiation therapy. For two weeks during radiation therapy, the women were randomly assigned to apply either aloe vera gel or the cream to the affected area. Results showed that aloe vera gel is less effective than a water-based cream in reducing radiation-induced skin side effects, such as peeling and pain.
Ulcerative Colitis 44 out-patients participated in a study of aloe vera gel and ulcreative colitis. Subjects were randomly assigned to receive either oral aloe vera gel or placebo for four weeks. Subjects receiving the aloe vera were more likely to get better, however the size of the trial was not large enough to determine whether the results were due to chance. In addition, results of sigmoidoscopes of the two groups revealed little difference. Only minor side effects were reported. The researchers concluded that further study is needed to determine the effect of aloe vera on patients with colitis.
Diabetes Researchers reviewed over 100 trials of herbs and supplements and their use in lowering glucose. The study included two trials of aloe vera. The trials were not randomized and were performed by the same investigators. The trials reported a reduction in blood glucose level after six weeks of aloe vera gel supplementation. No side effects were reported. Further study is necessary to determine the effect of aloe vera on blood glucose levels.
This product is regulated by the FDA as a dietary supplement. Unlike approved drugs, supplements are not required to be manufactured under specific standardized conditions. This product may not contain the labeled amount or may be contaminated. In addition, it may not have been tested for safety or effectiveness.
Aloe vera gel should not be confused with aloe juice or aloe latex, both of which contain anthraquinone, a potent laxative.
Despite the use of some oral dosages in clinical trials of ulcerative colitis, there is not enough evidence at this time to support the use of aloe vera by mouth or by injection. The risk of serious adverse effects is high, and several cancer patients died from aloe vera injections that were used as a cancer therapy.
You are taking glyburide, diuretics, or digoxin (This applies to use of aloe vera by mouth ONLY: As a laxative, oral aloe may further lower blood sugar or potassium levels if used for a long period of time).
Aloe vera is a tropical plant used in traditional medicine throughout the world. It has been studied for its ability to relieve constipation, treat burns, heal wounds, treat psoriasis, frostbite, ulcerative colitis and diabetes. Recent studies suggest that some components of aloe, such as acemannan, aloeride, and di(2-ethylhexyl)phthalate (DEHP) may have immunomodulating and anticancer effects (5)(7)(8). Emodin, an extract of aloe vera, inhibited cell proliferation and induced apoptosis in human liver cancer cell lines through p53- and p21-dependent pathways (4). Aloe is also thought to have antioxidant and anti-inflammatory properties (9). Concurrent administration of aloe with chemotherapy was reported to benefit patients with metastatic cancers (20). More research is needed. Data on external use of aloe products to alleviate radiation-induced skin damage are inconsistent (1)(2)(3). Aloe is used by many cancer patients but its anticancer effects have not been evaluated in humans.
It is presently believed that some of the beneficial effects of aloe result from inhibition of bradykinin by a contained carboxypeptidase. Aloe is also thought to hinder the formation of thromboxane, the activity of which is detrimental to healing of burn wounds (17). Laxative effect of aloe juice and aloe latex is caused by anthraquinone glycosides aloin A and B (16). Some studies have indicated that aloe vera may have anticancer effects. Emodin, an extract of aloe vera, can inhibit cell proliferation and induce apoptosis in human liver cancer cell lines through p53- and p21-dependent pathway (4). Acemannan, a carbohydrate fraction derived from aloe vera leaf, can stimulate cytokine production in mouse macrophage cell line (5). It also exhibited immunomodulating activity by inducing maturation of dendritic cells (6). Another in vitro study has indicated aloeride, a polysaccharide obtained from aloe vera juice, as a potent immunostimulator by increasing NF-kappa B activities (7). A compound, di(2-ethylhexyl)phthalate (DEHP), isolated from aloe vera can inhibit leukemic cells in vitro (8).
Aloe vera gel should not be confused with aloe juice or aloe latex, both of which contain anthraquinone, a cathartic laxative. Aloe vera taken for internal use should be discouraged due to possible adverse effects and inconclusive clinical data. Aloe vera injections for cancer patients have resulted in several deaths. The FDA rules that aloe is not safe as a stimulant laxative. (14)
Topical administration of aloe vera gel is considered safe but oral consumption of aloe can cause gastrointestinal upset and electrolyte abnormalities.
Inappropriate use of aloe vera supplements has been linked to thyroid dysfunction (10), acute hepatitis (11), and perioperative bleeding (12). Parenteral administration of aloe should be avoided due to potential toxicities and lack of clinical efficacy in humans.
A case of hypokalemia has been reported with use of aloe vera during chemotherapy (19).
Oral Glyburide: Aloe may increase hypoglycemic effects. Diuretics: Aloe may have additive hypokalemic effect due to diarrhea if used for a prolonged period. Digoxin: Aloe may have additive hypokalemic effect due to diarrhea if used for a prolonged period.
Topical Hydrocortisone: Aloe may increase anti-inflammatory effects. (15) Sevoflurane:Aloe may have additive antiplatelet effect causing excessive bleeding during surgery. (12)
Olsen DL, et al. The effect of aloe vera / mild soap versus mild soap in preventing skin reactions in patients undergoing radiation therapy. Oncol Nurs Forum 2001;28:543-7. A randomized, blinded, prospective study of patients undergoing radiation therapy. Seventy patients were randomized to receive skin care with either aloe vera and mild soap or mild soap alone. Time to skin change (texture, erythema, tanning, pruritus) was the primary measured outcome. Aloe vera product contained pure aloe vera gel in addition to d-alpha tocopherol, triethanolamine, and methylparaben. There was no statistically significant difference between the treatment arms at low cumulative dose(<2,700 cGy). Aloe vera added soap seems to have a protective effect on patients who received a higher cumulative radiation dose(>2700 cGy).
Heggie S, et al. A Phase III study on the efficacy of topical aloe vera gel on irradiated breast tissue. Cancer Nurs 2002;25(6):442-51. This is a Phase III trial involving 225 women with breast cancer who received radiation therapy after lumpectomy or partial mastectomy. Patients were randomized to receive either topical aloe vera gel or topical aqueous cream for 2 weeks after radiation treatment. The author concluded that aloe vera gel is less effective than aqueous cream in reducing radiation induced skin side effects, such as dry desquamation and pain.
