Algis, you must take doxycycline with a glass of water, or even better for people with sensitive stomachs, glass of milk. I used to take it first thing in the morning with a small glass of milk, after discovering that if I didn't take the milk, or at least water and biscuit or something, I would be as anything, even after not having eaten for twelve hours. You must do this to stop it damaging the lining of your oesophagus and stomach because it is very acidic. Stay upright as well! Then don't take either a calcium/magnesium supplement or any probiotics for at least two hours.
I only threw up once: I learned my lesson!
An Itinerary in Light and Shadow Completed Dr Charles Stratton / Dr David Wheldon abx regime for aggressive secondary progressive MS in June 2007, after four years. Still improving with no relapses since starting. Can't run but can paint all day.