I find it easier to use a 22 gauge needle because of the thickness of the oil. My Dr. gives me a 10ml bottle with one refill, and I would guess that he will do the math when I ask for another, so bumping it up will probably not be a good idea. Question.. I just got a friend request from edwin.wen1976, and accepted it without thinking. Reading the above posts, I wonder if I made a mistake. Thoughts?