Dried latex from the inner lining of aloe leaves has been used traditionally as a laxative taken by mouth. Although few studies have been conducted to assess this effect of aloe in humans, the laxative properties of aloe components such as aloin are well supported by scientific evidence. A combination herbal remedy containing aloe was found to be an effective laxative, although it is not clear if this effect was due to aloe or to other ingredients in the product. Further study is needed to establish dosing and to compare the effectiveness and safety of aloe with other commonly used laxatives.

Limited evidence from human studies suggests that 0.5% extract from Aloe vera in a hydrophilic cream may be an effective treatment of genital herpes in men (better than aloe gel or placebo). Although seemingly well designed, there may have been problems with the way these studies were conducted. Additional research is needed in this area before a strong recommendation can be made.

Evidence from one human trial suggests that 0.5% extract from aloe in a hydrophilic cream is an effective treatment of psoriasis vulgaris. However, there may have been problems with the way this study was conducted. Additional research is needed in this area before a strong recommendation can be made.

One study using 30% aloe lotion suggests effectiveness for treating seborrheic dermatitis when applied to the skin twice daily for 4-6 weeks. Further study is needed in this area before a strong recommendation can be made.

There is preliminary evidence from a small case-control study that oral aloe may reduce the risk of developing lung cancer. Further study is needed in this area to clarify if it is aloe itself or other factors that may cause this benefit.

There is weak evidence from two studies that treatment of recurrent aphthous ulcers of the mouth with aloe gel may reduce pain and increase the amount of time between the appearance of new ulcers. Further study is needed before a recommendation can be made.

Laboratory studies show that aloe can stimulate insulin release from the pancreas and can lower blood glucose levels in mice. Results from two poorly conducted human trials suggest that oral aloe gel may be effective in lowering blood glucose levels, although a third, smaller study found no effect. More research is needed to explore the effectiveness and safety of aloe in diabetics.

Acemannan, a component of aloe gel, has been shown in laboratory tests to have immune-stimulating and anti-viral activities. Results from early human studies are mixed, and due to weaknesses in the way these studies were designed, firm conclusions are not possible. Without further human trials, the evidence cannot be considered convincing either in favor or against this use of aloe.

Preliminary evidence suggests that aloe may be effective in promoting healing of mild to moderate skin burns. However, the existing studies are small and poor in quality, and therefore no clear conclusion can be drawn. Further study is needed in this area.

There is limited but promising research of the use of oral aloe vera in ulcerative colitis (UC), compared to placebo. It is not clear how aloe vera compares to other treatments used for UC.

Study results of aloe on wound healing are mixed with some studies reporting positive results and others showing no benefit or potential worsening of the condition. Further study is needed, since wound healing is a popular use of topical aloe.

There is preliminary evidence from a human trial that oral aloe vera does not prevent or improve mucositis (mouth sores) associated with radiation therapy.

One well-designed human trial found no benefit of topical acemannan hydrogel (a component of aloe gel) in the treatment of pressure ulcers.

Reports in the 1930s of topical aloe's beneficial effects on skin after radiation exposure lead to widespread use in skin products. Currently, aloe gel is sometimes recommended for radiation-induced dermatitis, although scientific evidence suggests a lack of benefit in this area.