Does my dermatologist care?

I had bad acne in about 9 years ago and my dermatologist prescribed me Accutane which eeffectively eliminated all my problems. But about a year ago I was told by a nurse friend to see a dermatologist about a little nasty reoccurring acne in on the back of my neck. It was very isolated and had been that way for a while. My dermatologist prescribed me Minocycline once a day for a month. It doesnt really mildly helped, but I noticed that I started having very mild break outs on my face and chest; thats something I hadnt had in years. He then prescribed 6 months of minocycline twice a day. I had the same results. Mild clearing of the head with more breaking out in other areas. My 6 months ended and when I stopped taking the minocycline, in about a week, I developed (what my doctor described) about 200 sores covering about 80% of my head. It was terribly painful and still kinda is. He decided to take a culture of my head and gave me a weeks worth of solodyn (another minocycline) once a day. I waited a week with only mild improvement and when I called his office for results, his staff said "everything was normal and he was prescribing another month of minocycline". I told them that was the same medication that didn't work before. They put me on hold and then came back with a prescription of Ciprofloxacin twice a day for a month. I have seen some improvement since I started taking it a few days ago, but I can't help but get the feeling that my doctor isn't paying attention to this. Should I stick with this doctor or get a second opinion?