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Treatment of antibiotic resistance will likely advance with better understanding of drug and genetic interactions. Physiological responses and genetic mechanisms in antibiotic-exposed bacteria remain poorly understood. Previous resistance studies have been conducted retrospectively, which lags in time and does not monitor the entire process of resistance development, and often have unpredictable dynamics. To determine how clinical isolates of <em>S. Typhimurium</em> responded to ciprofloxacin, we examined their adaptive responses, finding that <em>S. Typhimurium</em> RamA-mediated regulation directly perturbs microbial metabolism under ciprofloxacin, including genes involved in galactitol metabolic pathways, which facilitate adaptive responses to the drug therapy response and improving the efficiency of intracellular survival. A more complete and integrated understanding of these plastic physiological and microevolutionary genetic changes affects treatment outcome.