urinary tract infection
"Doxy works very well for me - no matter for what condition - but it makes me feel sick if 
I take it with dairy. I used to take it with yogurt. I learned to avoid dairy with, +/- 2 hrs before and after the med and I don't have problems anymore. Hope this helps. 
There is another trick. I have taken Doxy made in Europe and I never had any side effects - even when taken with yogurt. I have no explanation for this."