Thank you. I believe you will not have to see the worst of it, but the effects are a necessary evil and will linger until she is freed. Your patience will be appreciated.

[ which is cryptic as fuck! But McGonagall's sensible. Strange isn't outright going to say "I plan on dosing myself with concentrated madness because I'm worried this is a fairy's fault and that's the only way I'll actually be able to see the fiend in order to challenge him." ]