Azithromycin
"I have used this numerous times for both bronchitis and sinusitis and it has always worked great for me.  The 5 day z-pack is great.  I don't have to take a pill for 14 days and that is awesome.  Every time I have taken it, I have experienced stomach pain on the first day but each day following it, no problems.  This medicine is awesome and I highly recommend it to anyone who wants  fast and effective relief!!"