
Originally Posted by
Metalject
Certain guys can be allergic to certain esters, that's the very reason test cypionate was made because a small segment of the population is allergic to enanthoic acid.
You can also be allergic to certain oils, this can vary from one guy to the next quite a bit. Most people have no notable problems with any oil as long as it's clean, like Lunk said some have preferences like grape seed oil...I actually don't care for grape seed oil but that's just my personal preference and has nothing to do with it being quality or not.