@margedoc

With any injection of this nature you should leave the needle in for a good 10-15 seconds after the injection. This forms a kind of plug so the medication has time to be absorbed into the tissue before withdrawing the needle. Otherwise, when medications are initially injected, there is some back pressure and some of the medication comes back out. Leaving the needle in before withdrawing it will prevent the back flow so you get the full dose. If there is a small amount of back flow don't worry about it because you still get most of the dose. If some blood comes out just put some finger pressure on it with a sterile gauze or the alcohol wipe.

There are autopen injections but the same principle applies for not withdrawing immediately.

Sometimes people withdraw the needle before all the medication is injected--don't do that!