Bacteria become highly tolerant to antibiotics when nutrients are limited, and this tolerance is mediated by active starvation responses rather than passive growth arrest. The study shows that the stringent response (SR), a starvation-signaling pathway, controls antibiotic tolerance in nutrient-limited and biofilm-forming Pseudomonas aeruginosa. Inactivation of the SR significantly reduced tolerance and increased antibiotic efficacy. The SR reduces oxidant stress in bacterial cells, and its inactivation increases endogenous oxidative stress, leading to enhanced antibiotic sensitivity. The tolerance is also linked to the overproduction of 4-hydroxy-2-alkylquinolines (HAQs), which have pro-oxidant effects. However, impaired antioxidant defenses, not just HAQ overproduction, are required for antibiotic sensitivity. The SR also mediates tolerance in other Gram-negative bacteria, suggesting that oxidant stress regulation is a common mechanism. Infection models showed that SR inactivation improved antibiotic efficacy and prevented the emergence of resistant mutants. These findings highlight the role of starvation responses in antibiotic tolerance and suggest targeting these responses could enhance antibiotic treatment.Bacteria become highly tolerant to antibiotics when nutrients are limited, and this tolerance is mediated by active starvation responses rather than passive growth arrest. The study shows that the stringent response (SR), a starvation-signaling pathway, controls antibiotic tolerance in nutrient-limited and biofilm-forming Pseudomonas aeruginosa. Inactivation of the SR significantly reduced tolerance and increased antibiotic efficacy. The SR reduces oxidant stress in bacterial cells, and its inactivation increases endogenous oxidative stress, leading to enhanced antibiotic sensitivity. The tolerance is also linked to the overproduction of 4-hydroxy-2-alkylquinolines (HAQs), which have pro-oxidant effects. However, impaired antioxidant defenses, not just HAQ overproduction, are required for antibiotic sensitivity. The SR also mediates tolerance in other Gram-negative bacteria, suggesting that oxidant stress regulation is a common mechanism. Infection models showed that SR inactivation improved antibiotic efficacy and prevented the emergence of resistant mutants. These findings highlight the role of starvation responses in antibiotic tolerance and suggest targeting these responses could enhance antibiotic treatment.