<P> Aloin, a compound found in the exudate of some Aloe species, was the common ingredient in over-the - counter (OTC) laxative products in the United States until 2002 when the Food and Drug Administration banned it because the companies manufacturing it failed to provide the necessary safety data . Aloe vera has potential toxicity, with side effects occurring at some dose levels both when ingested or applied topically . Although toxicity may be less when aloin is removed by processing, Aloe vera that contains aloin in excess amounts may induce side effects . </P> <P> Aloe vera juice is marketed to support the health of the digestive system, but there is neither scientific evidence nor regulatory approval to support this claim . The extracts and quantities typically used for such purposes appear to be dose - dependent for toxic effects . </P> <P> Aloe vera is used in traditional medicine as a skin treatment . In Ayurvedic medicine it is called kathalai, as are extracts from agave . Early records of Aloe vera use appear in the Ebers Papyrus from the 16th century BC, and in Dioscorides' De Materia Medica and Pliny the Elder's Natural History--both written in the mid-first century AD . It is also written of in the Juliana Anicia Codex of 512 AD . The plant is used widely in the traditional herbal medicine of many countries . </P> <P> Aloe vera is used on facial tissues where it is promoted as a moisturiser and anti-irritant to reduce chafing of the nose . Cosmetic companies commonly add sap or other derivatives from Aloe vera to products such as makeup, tissues, moisturizers, soaps, sunscreens, incense, shaving cream, or shampoos . A review of academic literature notes that its inclusion in many hygiene products is due to its "moisturizing emollient effect". </P>

What types of aloe vera plants are there