asthma
"I had a sinus infection and was prescribed prednisone, erythrocin and albuterol all together. After my first treatment of only antibiotics - it did not do the job.  Not really sure what each of them are responsible for EXACTLY.  Erythromycin is the antibiotic and albuterol is for opening air tight passageways in the lungs that caused wheezing [asmathic reaction due to the sinus infection]. The prednisone, while I don't like the idea of taking a steroid, did a good job of helping to recover.  The only side effect I noticed was an increase in appetite."