greylock
There are quite a few people who do not recommend the internal use of aloe vera. They say that it is fairly common to have an adverse reaction - such as developing an allergy to the aloe vera - if it is taken internally.
I do use aloe vera externally, especially for mild burns and sun burns. Recently I had a steam burn and kept the aloe vea on it for about 20 or thirty minutes continuously and then let it dry. Healed up very nicely.
There are a number of different plants that people call aloe vera - I'm not expert enough to judge which are truly aloe vera and which are simply "miscellaneous aloe". But I find all of them seem to work pretty well.
I would not use aloe vera on lacerations or punctures.