[Mark_F]

I have been taking Cephalexin twice a day for a few years for adult acne. My dermatologist was concerned about prolonged use, and has taken me off Cephalexin, and put me back on minocycline. My acne has returned with a vengeance.
Why is my dermatologist concerned about prolonged use of Cephalexin - what are the possible complications?

Many years ago, my doctor prescribed Tetracycline for my acne, which worked for a couple years, and then my acne returned. I was then prescribed Minocycline, which again worked for a couple years, then my acne returned, so I went to a dermatologist who prescribed Cephalexin which I have been taking for about 3-4 years. It was still working fine. He changed my prescription back to Minocycline about a month ago, and my acne has been steadily getting worse. He told me it wasn't good to be taking Cephalexin for so long. Why?

Thank you!
Mark