I take minocycline, twice a day, and i found positive outcomes from it. I'm not sure that what you are experiencing is directly from the minocycline, it could be just coincidental. Unless you have never had a whitehead before. One other though would be that, i think that minocycline is designed to heal your acne so it might be just drawing out the bacteria inside your pores, therefor leaving them in whitehead form. I am no dermatologist, so i probelly don't know exactly what i'm talking about.. But those are just my ideas