Doxycycline
"Had really bad sinus infection, tried Augmentin - didn't help. After that my dr prescribed Ambroxol AL (available in Germany - combination of ambroxol hydrochloride (secretolytic agent for mucus) and doxycycline 100 mg - after only two days I started feeling much better - my nose and ears were clear and I felt much better in general. No side effects, since I took it after meal (not on empty stomach)."