Got a virus a few weeks ago, tried sinus meds., then cold/cough medicine. No avail. Five days ago, a doctor gave me 5 Zithromax caplets at 250mg. each. Took the last one tonight. Still feel short of breath. At times it gets real bad, like my heart races because my air is blocked. Like an indigestible, heartburn problem. I have taken a few heartburn pills too at times.