Okay there is a huge difference between discomfort and pain. Know the difference. Your body is the most complicated system and most complex system known to man. Your body is built with built in safety mechanisms as well as the ability to maintain, fix, heal and regenerate itself on some levels. Your body experiences discomfort to let you know that you are pushing it to the limits. It experiences pain when you have pushed it too far. Some things in your body when they are broken and then fixed are actually stronger than they were to start with, bones for example. Other things well, not so much. Muscles for example are an example of this. Once a muscle is cut or damaged it is significantly weaker as a result. That's why so many of us especially those of us who have had abdominal surgeries end up with hernias for example.
Next thing is, anal injections of any kind are not a good idea. We are all aware of hemorrhoids, piles, or whatever you want to call them, especially those of us who work on cement, have had vaginal births, or like anal play. What do you think those are? Those are blood vessels. When they get angry they swell up and form hemorrhoids. There are a lot of blood vessels in the rectal area. So if you are not a medical professional, how are you going to know anatomy well enough not to inject one of those? So lets say for example you don't quite have the area as sterile as you think. You insert a needle that has even a few bacteria on the tip of it and you introduce that right into the blood stream. 3 days later the person you played with or your loved one gets sick. You take them to the ER and they are diagnosed with sepsis. They may live and they may not.
So getting back to anal insertions/stretching. Again, pain vs. discomfort. Please know the difference. I have used products like anal ease before, but do so with caution. I know Doc and his limits more so than I probably know my own. I know what he can handle and what he can't. I usually use the numbing product at the very start of play, just as a warm up to help get him relaxed. When the product is working I am using that time to play in him with A finger, maybe 2 but no more. Besides that, we like anal play, we want to feel our asses being played with. If you are numb then that pleasure is gone and then what's the point?
Since being a mod on this forum for the past 6 years I have learned a very valuable lesson and that lesson is this, I can't fix stupid. All I can do is give you my honest opinion as someone who has basically experienced a lot of things medically speaking in a play setting, and my medical advice as a professional. So there you have it. That's my advice.
Mashie