Resistance to Antimicrobial Agents: From Bacteria to Yeast

In this chapter, a brief review of the state of the art regarding the main types of antimicrobial compounds and their resistance mechanisms is presented. Resistance to antimicrobial compounds is a worldwide problem, requiring urgent action and global response. Drug resistance (in this case to antimicrobial compounds) could be in many cases one natural response due to the selective pressure of the active pharmaceutical ingredient, which will be intensified by various causes, like abuse, underuse or misuse, inadequate drug adherence, or low quality of the drug available.