Optimizing dosage to prevent emergence of resistance - lessons from in vitro models.

The widespread emergence of resistance to antimicrobial agents has taken mammoth dimension and warrants immediate steps to minimize it. Pharmacokinetics/pharmacodynamics of antimicrobial agents, differences among bacterial species, and time-dependent changes in the bacterial population are important factors involved in the development of drug resistance. The key to minimizing resistance lies in understanding how these factors affect resistance emergence and incorporating them in dosing regimen design. In vitro models have proven to be a valuable tool to study these factors and their contribution in resistance emergence. This review summarizes the key factors implicated in resistance development and the lessons learnt from in vitro studies optimizing antimicrobial dosing to prevent resistance emergence.