65 years old with bad cough and high fever. on zpak and not getting better.?

How long?: How long have symptoms been bothering you? How many of the zithromycin pills have you taken? It is a broad spectrum antibiotic, usually given 2 pills as a "loading" dose and 1 each day thereafter for 5 days. If not getting better at the end of medication, another consult with md is indicated. Pneumonia needs to ruled out, as it is a very serious problem for older patients.