raspberryswirlgirl -
Fainting was one of my strange sx long before I even suspected Lyme & Co. I tended to take showers that were too hot or once I sat in a hot tub too long, or sat in saunas too long, or visited Pheonix in July... all related to heat. Yeast/fungus doesn't like the heat and die off can be significant - both the y/f growth and the die off can release neurotoxins like ethanol.
Lyme & Co prefers a cool environment too. So heating up the body can also cause weird symptoms.
Another thing your LLMD might check is a circulatory interference like with POTS.
I LOVE the fact that he's given you a y/f protocol first - as these associated symptoms can overlap w/ Lyme & Co quite a bit and cause a lot of confusion and difficulty with the Lyme & CO treatment. So this will help prepare you a little better for all the abx and reduce common side effects with them.
Here is more info on y/f if you're interested:
Y/FO post in the "New to Lyme?" thread:
www.healingwell.com/community/default.aspx?f=30&m=1606610&g=3644275#m3644275-p