I Have Throat Infection And Throat Burning. Doctor Prescribed Erithromycin500

I have throat infection and throat burning. Doctor prescribed Erithromycin500 and it is very old drug(I am65 yers). Pharmacist gave me AZITHRO *500 saying it is same, but the Company Albums Drugs & Pharmaceuticals Ltd (Marketed by WOCKHARDT Ltd. I THINK without giving Dr's prescription, I might be cheated for more commission in the tablets he gave differently. Can use this or Dr' prescribed medicine. Early reply will be helpful. PHARMACIST medicine can be used or I have change the ta let's.
Thanking you,
P. HariShankar