Which Drug Taken For Fall Could Cause Grey Skin Around Nose, Mouth And Ears?

I am a student nurse, and while shadowing in the ED, a patient came in because of a fall. However, the skin around his nose, mouth and ears was dark gray/black or sooty colored. He said it was a side effect of a medication he has to take. I didn t get the spelling, but it sounded like micacylin. Can you provide any further information or perhaps the correct spelling of a drug with this side effect? Thank you.