Cephalexin is effective primarily against which type of bacteria?

Cephalexin is a first-generation cephalosporin antibiotic that predominantly targets Gram-positive bacteria. The structure of cephalexin allows it to effectively disrupt the cell wall synthesis of these bacteria, which typically possess a thick peptidoglycan layer. This mechanism of action is critical for the efficacy of cephalexin, as it interferes with the integrity of the bacterial cell wall, ultimately leading to cell lysis and death.

While cephalexin does have some activity against certain Gram-negative organisms, its primary effectiveness is noted in treating infections caused by Gram-positive bacteria, such as Staphylococcus and Streptococcus species. Understanding the targeted spectrum of cephalexin is important for clinical decision-making when choosing antibiotics for infections, as it influences how practitioners will select appropriate therapy for their patients based on the suspected or confirmed bacterial pathogens.