Antimicrobial activity of psychotropic drugs: selective serotonin reuptake inhibitors.

Psychotropic drugs have been shown to have antimicrobial activity against several groups of microorganisms. Some of these drugs, such as the new antidepressant agents sertraline, fluoxetine and paroxetine are known to act as efflux pump inhibitors in human cells. Their activity has been studied, alone and combined with antibiotics, against bacterial species, mainly in multiply resistant strains. These agents have surprising activity, mainly against Gram positive microorganisms. They also show synergistic activity when combined with some antibiotics against several bacteria, shown by a decrease in MICs, that converts strains previously resistant to the category of sensitive, and modify physiological aspects related with pathogenicity.