Montelukast treats <i>Streptococcus pneumoniae</i> -induced sepsis via antibacterial and anti-inflammatory activities

Montelukast showed promise as a repurposed treatment for multidrug-resistant <i>Streptococcus pneumoniae</i>, especially in severe infections like sepsis. It demonstrated strong <i>in vitro</i> activity against both sensitive and resistant strains and exerted concentration-dependent bactericidal effects and cleared biofilms. In a mouse sepsis model, montelukast improved survival, reduced bacterial load, and mitigated inflammation. Mechanistically, it disrupted membrane integrity and induced oxidative stress and may target pseudouridine synthase. These findings supported montelukast's potential as an antimicrobial with dual antibacterial and anti-inflammatory action.