The potential of drug repurposing to face bacterial and fungal biofilm infections

Abstract The emergence of multidrug-resistant microorganisms in persistent biofilm infections represents a public health threat. The limited efficacy of currently available antimicrobials has been imposing the search for new approaches to overcome bacterial and fungal biofilm infections. Drug repurposing arises as an interesting strategy that can reduce time, cost, and risk associated with drug innovation. This can be achieved by finding new applications beyond the original medical indication for approved or investigational drugs. This chapter collects the antimicrobial effects known so far against bacteria and fungi caused by different classes of drugs, including antineoplastic, antipsychotic, antidepressant, and antiinflammatory, among others. Besides the action on microbial growth in vitro and in vivo, some of these drugs are also able to synergize with traditional antibiotics and antifungals. Finally, a special focus on antibiofilm activity was included, reveling the promising drugs for biofilm prevention and control.