The amount that gets lost is minimal. If you just pull the pin out and press your wipe to the site, right away, you'll be ok. when muscles that have a little more give to the skin, you can use the Z track method. After you clean the site and are ready to inject, pull the skin to one side with your free hand, before inserting the needle, then after you pull the pin out and it will close the injection hole. You can find videos showing how to do the Z track method on youtube. If you never use this method, you'll be fine though. Your body will probably never know the difference of the few mg's loss