And ive only taken it up the ass once. It didnt work that well. It was when i was starting out and i think i went to the inside too much instead of upper outer ass. I dont know you you guys reach around to do ass.
You can but, I would watch what your injecting I wouldnt suggets no shit like Test 400 in the shoulders but yes it can be done..But as already stated, Don't make a habit of it