A black mark on feet has appeared. What could be the reason of it. I had an ankle sprain a '3 weeks' back, and afterwards was taking a treatment where in calciumvitamin D suppliments was given alongside an anti inflamation medicine, "trypsin, bromelain and rutoside." I wish to know the possible reason, the possible diagnosis. And if at all is it a matter of concern and should be checked on by a doc. Its been 4 days that i have taken no medicine. And only today have i encountered this, black mark. .. besides this, i have a slight pain in the right hand wrist. Its a normal pain by the feeling of it. But wanted to tell to see if the 2 have, or have not any correaltion