Grams positive disc.The antibiotic discs (per unit disc) used for antimicrobial susceptibility of Gram-positive bacteria were as follows: oxacillin (5 mcg), ampicillin (10 mcg), cephalexin (30 mcg), ceftriaxone (30 mcg), cefotaxime (30 mcg), ceftizoxime (30 mcg), erythromycin (5 mcg), azithromycin (15 mcg), clindamycin (2 mcg),