Red lines on back changing with abx treatment

So now my other son has lyme, was confirmed a few weeks ago. The only difference with him and my younger son is he has the red stretch mark-like lines on his back, bartonella if you know lyme and stretch marks if you are every other doctor.
He started on doxy and biaxin about two weeks ago and I noticed there are more lines now, is that normal? Will the abx cause a change in these lines?

Def. herxing, push through it. You want to catch bart before it gets really bad like my son! I think it's worse than lyme...

Our daughter improved more with Buhner's herbs than she did with 2 years of antibiotic treatment. Her PANS is completely resolved now and she made an easy transition to high school.

Keep up the good work - your son will get better.