Hello. You seem to have quite severe lung infection i.e. pneumonia. Z-pak which is Azithromycin is a good antibiotic for chest infections. But since you have developed a new symptom i.e. coughing up blood, I would presume Z-pak is not working in your case. I would advise you to get a chest Xray which will show us the pattern and severity of the pneumonia. I generally also advise sputum microscopic examination as well as culture and sensitivity for my patients as it shows what organism is causing the infection and what works against it. Till the reports are obtained I would advise addition of another broad spectrum antibiotic. If Tuberculosis is prevalent in your area or country, testing for it becomes important as the treatment is different from that for other chest infection causing bacteria. It can generally be seen on sputum microscopy as well as certain other blood tests. Hope this helps. Regards, Dr Geeta