Ikkinchi avlod sefalosporin antibiotigi, parenteral qo'llash uchun. Bakteriyalarning asosiy oqsillari bilan bog'lanish orqali hujayra devorining sintezini buzib, bakteritsid ta'sir ko'rsatadi. Beta-laktamaz ishlab chiqaradigan shtammlarni o'z ichiga olgan keng spektrli patogenlarga qarshi faol. Gram-musbat mikroorganizmlar, shu jumladan penitsillinga chidamli (lekin metitsillinga chidamli shtammlardan tashqari) shtammlarga nisbatan yuqori faollikka ega. Bu mikroorganizmlar qatoriga Staphylococcus aureus, Streptococcus pyogenes (va boshqa beta-gemolitik streptokokklar), Streptococcus pneumoniae, Streptococcus agalactiae, Streptococcus mitis (viridans guruhi), ko'pchilik Clostridium spp. kiradi.
Gram-manfiy mikroorganizmlarga qarshi faol: Escherichia coli, Klebsiella spp., Proteus mirabilis, Providencia spp., Proteus rettgeri, Haemophilus influenzae (shu jumladan ampisillinga chidamli shtammlar), Haemophilus parainfluenzae (ampisillinga chidamli shtammlar), Moraxella catarrhalis, Neisseria gonorrhoeae (penitsillinaza ishlab chiqaruvchi va ishlab chiqarmaydigan shtammlar), Neisseria meningitidis, Salmonella spp., Borrelia burgdorferi. Shuningdek, gram-musbat va gram-manfiy anaeroblarga nisbatan ham faol: Peptococcus spp., Peptostreptococcus spp., Fusobacterium spp., Propionibacterium spp.
Cefuroksim quyidagi mikroorganizmlarga ta'sir qilmaydi: Clostridium difficile, Pseudomonas spp., Campylobacter spp., Acinetobacter calcoaceticus, Listeria monocytogenes, metitsillinga chidamli Staphylococcus aureus va Staphylococcus epidermidis, Legionella spp., Streptococcus (Enterococcus) faecalis, Morganella morganii, Proteus vulgaris, Enterobacter spp., Citrobacter spp., Serratia spp., Bacteroides fragilis.