No, you cannot have it done whilst breastfeeding, it's a toxin after all.

...until I found out it's a routine treatment for anal fissure issues these days !
Yep, this is why I know you can't do it whilst b'feeding, I have a very good friend who had to wean her DS in order to have this procedure done.

I've been telling DH for a few years that I want it done between my eyes. I will seriously consider it once this new baby has finished feeding. He is also against it but hey, it's my face!