Things that cause a BGL spike?

If you're needing painkillers, it is more likely the pain that raises blood glucose than the tablets. I never noticed a rise and i've used both, frequently. As for mouth wash, I dunno.... If it tastes sweet, it might. (Your pancreas pre-emptively pumping out insulin you don't need, and your liver over-correcting for it with a glucose dump).

 

I haven't noticed any BGs rises with mouthwash (Listerine) and with either paracetamol or ibuprofen but, as @JoKalsbeek says above, pain can increase BGs as can anxiety.

 

Xylitol chewing gum. Unless there's pets to consider, as xylitol's potentially deadly).

 

Paracetamol is safe for pain, ibuprofen is in my case a non starter, it causes a side effect of stomach problems., as for mouth wash, I would imagine that all of them contain some form of sweetener, sugary taste.
And if any drug contain something which you are intolerant to then yes it can push you out of ketosis.
Do be careful what you do take.

Keep safe.