We had an incident the other night that could have quickly turned worse and require the use of the glucagon. My husband asked me, how much do we use now?
First, keep in mind that as your child gets older/heavier that the amount needed will change.
Second, don't throw the old one out! Practice on it. It's going in the sharps bin, so you might as well practice taking the safety off, mixing it and injecting it (into the sink or an orange of course).
Luckily in our case we didn't need it, and hope we never do, but it's always good to be familiar with how it works.