Can Azithromycin Be Used Immediately After Doxycycline?

I needed to take doxyclyline, however I find it difficult to swallow pills, so was told you open them and put them in water. I managed to swallow two pills, on the third I threw up. I now want to try azithromycin as they are smaller and u take them all the same day rather then two for seven days. Is it safe to start using azithromycin so soon after doxy?