For people having stomach problems: There is a brand name of dox...

For people having stomach problems: There is a brand name of doxycycline called "Doryx" that is enteric coated so that it goes through the stomach and dissolves in the intestine instead, so that it doesn't cause stomach symptoms. Ask your doctor to switch to "Doryx". With regard to diarrhea, I would recommend going to your local health food/supplement shop and picking up a probiotic like acidophilus in the refrigerated section (or perhaps a combination product with different probiotics). This will help to replenish "friendly" bacteria in the intestinal tract and prevent diarrhea if you take it at least twice daily. Just be sure to take it far away from your doxy dose. With regard to thrush and yeast overgrowth, ask your doctor for some Nystatin. Nystatin is a very, very non-toxic anti-fungal with virtually no side effects most of the time. It is not absorbed from the intestinal tract. It is used to clear yeasts like candida from the mouth and digestive tract. It comes in both tablets and powder. If purchased in tabs, be sure to chew the tablets and swish the contents around in the mouth before swallowing.