The drug is azithromycin, a commonly-used antibiotic. To treat (preferably early-stage) Covid it was prescribed in addition to hydroxychloroquine. It sounds you are not in the early stage.
You need another doctor, NOW. If you know any doctors or nurses personally, call them. Call emergency rooms. Make a pest of yourself. You may need to call an ambulance.
we were in early stage ...literally at the first sign my son was showing symptoms.