I think there was an article last week the mentioned a rare side effect of benzocaine turning blood blue. Found it: https://www.nbcnews.com/health/health-news/c

I think there was an article last week the mentioned a rare side effect of benzocaine turning blood blue. Found it: https://www.nbcnews.com/health/health-news/common-numbing-medication-turned-woman-s-blood-blue-n1055991 https://www.nbcnews.com/health/health-news/common-numbing-me...