100 mgs twice a day is not nearly enough Doxy, even for treatment of very early stages of Lyme. And the bulls eye rash confirms Lyme completely. It's the only infection that creates a bulls eye - so be sure that you have taken pictures of it with something like a dime or ruler in the picture to show the size.
I would encourage you to not only stay away from your primary care doc, but that doctor that calls themselves a LLMD - neither of them follows the ILADS protocols - which happens to be the only protocol that is now listed in the National Guidelines Clearinghouse.
You will want to find a well trained doctor, not one that has self proclaimed themselves as a LLMD or an ID Doc (Infectious Disease Doctor), as ID docs believe Lyme is hard to catch and easy to treat, and don't believe in the reality of chronic Lyme. Go to the ILADS site to read the new (2014) Treatment guidelines and you can see that your husband should have at least been put on 200 - 300 mgs twice daily, which is twice the amount he was prescribed. :
www.lymenet.org/BurrGuide200810.pdfBecause he is diabetic, he will have to be more concerned with his immune system recovering, I believe, and to be sure that he gets appropriate treatments. I'm not aware of any other complications with Diabetics that have gotten these infections, but I've also not looked into it.
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