The antidepressant drugs fluoxetine and duloxetine produce anxiolytic-like effects in a schedule-induced polydipsia paradigm in rats: enhancement of fluoxetine's effects by the α2 adrenoceptor antagonist yohimbine.

Similar to the time-course for treating depression, several weeks of administration are required for serotonin (5-HT) reuptake inhibitors to produce anxiolytic effects. Previous studies with the schedule-induced polydipsia paradigm (a putative preclinical anxiety model) have shown that repeated administration of antidepressant drugs is necessary to produce a suppression of polydipsia, which is interpreted as an anxiolytic-like effect. The present study sought to expand past findings by evaluating the selective 5-HT reuptake inhibitor (SSRI) fluoxetine and the 5-HT-norepinephrine reuptake inhibitor duloxetine in the schedule-induced polydipsia paradigm with rats.