Azithromycin
"On my 2nd package of 5 day Z pack, it is working but slow to act.  This is a bad infection, it had been on and off for past 6 months.  I will need another refill today or my Dr. may try another option.  I can not take any cyllin drugs.  This sinusitis is a chronic problem.  I was experiencing this problem almost yearly every fall/winter then stopped for past 5 years.  Now it is  back with vengeance..."