- Aloe gel
- aloe leaf
For Patients & Caregivers
Tell your healthcare providers about any dietary supplements you’re taking, such as herbs, vitamins, minerals, and natural or home remedies. This will help them manage your care and keep you safe.
What is it?
Aloe vera is a succulent plant that’s used in traditional medicine. The clear gel from its leaves can be put on the skin as a moisturizer and to treat burns. Some people drink aloe vera juice as a laxative (something that helps you poop). Aloe latex (yellow substance that comes from just under the plant’s skin) is also used as a laxative.
You can inject aloe vera into your body as an alternative cancer therapy, but this can cause severe side effects including death.
What is it used for?
Aloe vera gel (put on the skin) is used:
- To treat burns
- To reduce swelling, itchiness, or redness
To reduce redness, rashes, and itchy skin caused by radiation therapy. It’s also used to decrease redness and swelling of mouth caused by chemotherapy.
- To improve blood sugar level in patients with diabetes (when taken by mouth)
Aloe vera has other uses that haven’t been studied by doctors to see if they work.
It’s generally safe to use aloe vera as a gel on your skin. But taking supplements or giving yourself an aloe vera injection (shot) can cause serious side effects.
Herbal supplements can also interact with some medications and affect how they work. For more information, read the “What else do I need to know?” section below.
What are the side effects?
What else do I need to know?
- Let your healthcare provider know if you are taking sevoflurane (Ultane®). This is an anesthetic (medication to make you sleep during surgery). Aloe vera may cause excessive bleeding during surgery.
- Aloe vera isn’t an effective cancer treatment, and it should not be taken as a supplement or injection because it can cause serious side effects.
For Healthcare Professionals
Aloe vera is a perennial, succulent plant that resembles a cactus and is used in traditional medicine throughout the world. The clear thick gel obtained from aloe leaves is used for wound healing, to treat burns, psoriasis, frostbite, ulcerative colitis, diabetes and to relieve constipation. Aloe demonstrated antioxidant and anti-inflammatory properties, in vitro (9).
In clinical studies, an Aloe vera cream was reported to be superior to silver sulfadiazine creams for the treatment of second-degree burns (21); an aloe gel was shown effective in skin graft donor-site healing (38); an aloe ointment improved symptoms of acute radiation proctitis in patients receiving radiotherapy (39); and an aloe cream improved postoperative pain and discomfort, and promoted healing following pilonidal sinus excision (45). A mouthwash containing aloe was shown to reduce plaque, gingivitis and S. mutans in the oral cavity in children, with the effects being comparable to chlorhexidine (46). Systematic reviews indicate aloe’s effectiveness against oral lichen planus, while not causing any adverse effects compared to corticosteroids (37); and for reducing pain/burning sensation and affecting clinical improvement in patients with oral submucous fibrosis (41). In addition, aloe gel complex was shown to affect reductions in body weight and insulin resistance in obese individuals with pre-diabetes or early untreated diabetes mellitus (29); to prevent pressure ulcers in hospitalized orthopedic patients at risk of developing such ulcers (42); to prevent traumatic oral ulceration in patients with fixed orthodontic appliances (47); and to accelerate split-thickness skin graft donor-site healing (43).
Data also suggest that constituents of aloe, such as acemannan, aloeride, and di(2-ethylhexyl)phthalate (DEHP) have immunomodulating and anticancer effects (5) (7) (8) (34) (35). Emodin from aloe inhibited cell proliferation and induced apoptosis in human liver cancer cell lines through p53- and p21-dependent pathways (4); along with enhancing the effects of radiation treatment (30). Concurrent administration of aloe with chemotherapy may prevent oral mucositis in patients receiving chemotherapy (23); along with benefitting those with metastatic cancers (20). However, findings of external use of aloe products to alleviate radiation-induced skin damage are inconsistent (1) (2) (3) (32) (36) (44).
Mechanism of Action
Several studies have been conducted to explore the mechanisms of action of aloe.
Oligosaccharides isolated from aloe extracts were found to prevent ultraviolet radiation-induced suppression of delayed type hypersensitivity by reducing keratinocyte-derived immunosuppressive cytokines (25). Proposed mechanism underlying anti-psoriatic effect includes inhibition of tumor necrosis factor (TNF)‑alpha‑induced proliferation of keratinocytes and overactivation of the nuclear factor (NF‑kappa B signaling pathway, by an aloe polysaccharide (40). And a polymer fraction of aloe was shown to protect the gastric mucosa against ethanol-induced gastric damage by decreasing mRNA expression levels of inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), and matrix metalloproteinase (MMP-9). The three enzymes are critical biomarkers in gastric ulceration (26). Other findings suggest that the radio-protective effects of aloe polysaccharides are most likely due to inhibition of apoptosis (27).
Emodin, an extract of Aloe vera, was shown to inhibit cell proliferation and induce apoptosis in human liver cancer cell lines through p53- and p21-dependent pathways (4). Acemannan, a carbohydrate fraction derived from Aloe vera leaf, was found to stimulate cytokine production in mouse macrophage cell line (5). It also exhibited immunomodulating activity by inducing maturation of dendritic cells (6). And aloeride, a polysaccharide obtained from aloe vera juice, was reported to be a potent immunostimulator that acts by enhancing NF-kappa B activities (7). In addition, di(2-ethylhexyl)phthalate (DEHP), isolated from Aloe vera, inhibited leukemic cells, in vitro (8).
Aloe gel should not be confused with aloe juice or aloe latex, both of which contain anthraquinone, a cathartic laxative. Aloe taken for internal use should be discouraged due to possible adverse effects and inconclusive clinical data. Aloe injections for cancer patients have resulted in several deaths.
The FDA rules that aloe is not safe as a stimulant laxative.
- Topical administration of aloe gel is considered safe but oral consumption of aloe can cause gastrointestinal upset and electrolyte abnormalities.
- Inappropriate use of aloe supplements has been linked to thyroid dysfunction (10), acute hepatitis (11), and perioperative bleeding (12).
- A case of hypokalemia has been reported with use of aloe vera during chemotherapy (19).
- Three cases of toxic hepatitis were reported following use of aloe preparations. Liver function was normalized after discontinuing aloe (22).
- Long term exposure to Aloe vera can cause cancer in animals (28) .
- Positive re-exposure tests have been reported with aloe, which highlight the herb’s potential for inducing liver injury (33).
- Cytochrome P450 substrates: In vitro, aloe juice was found to inhibit CYP3A4 and CYP2D6 and can affect the intracellular concentration of drugs metabolized by these enzymes (24). Clinical relevance is not known.
- Sevoflurane: A case report showed that additive antiplatelet effects with aloe resulting in excessive bleeding during surgery (12).