I have checked with my LC and my own Dr. Hale book and cannot find anything on this:
Sodium Hydroxide. I have an recurring ingrown toenail that I have been a slave with going back and forth to toe doc. I'm over going there and getting avulsions (removing the ingrown portion of the nail) and the podiatrist suggested I get this solution dabbed on to kill the root of the ingrown toenail. She said it's on there for merely seconds and then she pours vinegar over it to stop it. So, it's topical. My LC said, unless baby is sucking on my toes, that it's probably fine .
Just wanted to double check on here as I cannot find anything that says not to. It's a chemical but it is topical and its on for seconds. This is done after a local (the safe one - can't remember which one though).