A glucose tablet and a glucagon shot can both be used in emergencies, but they are best used to treat different levels of emergencies. You can take a glucose tablet if you're coherent and conscious, but when you're incoherent or passed out from a severe hypoglycemia, someone else administering a glucagon shot is a lot easier and safer.

Okay that makes sense. Thanks.

How quickly does a glucagon shot trigger GNG and how quickly can GNG raise glucose levels?

In my experience it takes just a minute or two