> extra adrenaline to fully numb it,

That's not what they usually use... but people have different reactions to novacaine, and different innervation; for dental work, there's a couple typical options for where nerves are and which nerves cover which teeth, some of which need more shots in more places.

For the GP, most likely the anesthetist put a note in the chart that they need more or different drugs to go under.

Can confirm.

My lips and gums go numb but my teeth generally do not. I am sure it takes the edge off, but I can still feel it and it is still incredibly uncomfortable.

On the other hand, while having a tooth pulled and opting to be put under, the nurse and I were having a great laugh after because I was so awake. Apparently there are multiple drugs and whatever the first one was hit me so hard they only have me a half dose of another. It was enough though. They said count, I hit nine, and I woke up somewhere else. Exactly what I wanted considering local doesn't work.

I'm from Germany and adrenaline is used as an addition as a vasoconstrictor here. There are quite a few differences between countries when it comes to anesthesia.

Also, even with the same person Novocaine can react differently sometimes (I've had enough cavities to know). And if you have an infection, that counteracts the Novocaine so they have to give you more (had that one happen to me too). Medicine is complicated, yo.