The Culprit

Clindamycin

Excerpt:

The most severe common adverse effect of clindamycin is Clostridium difficile-associated diarrhea (the most frequent cause of pseudomembranous colitis). Although this side-effect occurs with almost all antibiotics, including beta-lactam antibiotics, it is classically linked to clindamycin use

Comment: I'm not playing "the blame game" here, but I checked today and when I had oral surgery on December 20th, I was given a shot of Clindamycin.