Photodynamic therapy (PDT) is a treatment that combines a non-toxic dye (photosensitizer, PS) with low-intensity visible light to produce cytotoxic species, targeting both Gram-positive (G+) and Gram-negative (G-) bacteria. PDT has shown promise in killing pathogenic microorganisms in vitro and has been explored for treating infections in animal models and some clinical trials, primarily for viral lesions, acne, Helicobacter pylori infection, and brain abscesses. The key advantages of PDT include its dual selectivity, where the PS can be targeted to specific cells or tissues, and the light can be directed to the lesion. However, effective PDT requires the PS to be selectively delivered to microbes over host cells, and the ability to effectively illuminate the lesion. Recent studies have shown that multi-antibiotic resistant strains are equally susceptible to PDT as naive strains, and bacteria do not readily develop resistance. Future applications of PDT in infections include wounds, burns, rapidly spreading soft-tissue infections, abscesses in body cavities, and surface infections of the cornea and skin. The potential of PDT lies in its ability to target localized infections, where antibiotics may be less effective due to poor perfusion or biofilm formation.Photodynamic therapy (PDT) is a treatment that combines a non-toxic dye (photosensitizer, PS) with low-intensity visible light to produce cytotoxic species, targeting both Gram-positive (G+) and Gram-negative (G-) bacteria. PDT has shown promise in killing pathogenic microorganisms in vitro and has been explored for treating infections in animal models and some clinical trials, primarily for viral lesions, acne, Helicobacter pylori infection, and brain abscesses. The key advantages of PDT include its dual selectivity, where the PS can be targeted to specific cells or tissues, and the light can be directed to the lesion. However, effective PDT requires the PS to be selectively delivered to microbes over host cells, and the ability to effectively illuminate the lesion. Recent studies have shown that multi-antibiotic resistant strains are equally susceptible to PDT as naive strains, and bacteria do not readily develop resistance. Future applications of PDT in infections include wounds, burns, rapidly spreading soft-tissue infections, abscesses in body cavities, and surface infections of the cornea and skin. The potential of PDT lies in its ability to target localized infections, where antibiotics may be less effective due to poor perfusion or biofilm formation.