Fluoxetine hydrochloride (Lilly110140) is the first highly specific serotonin uptake inhibitor. It is used as an antidepressant and often has a more acceptable side-effects profile than traditional antidepressants.

When co-administered in adult male SD rats, fluoxetine and olanzapine induce a robust and sustained increase in extracellular dopamine levels, with concentrations surpassing baseline by 361% and 272%, respectively—significantly higher than when either drug is used alone. Additionally, fluoxetine reverses the prolonged latency of escape caused by unavoidable shocks in adult male SD rats.

Fluoxetine accelerates the maturation of immature neurons. It enhances the proliferation of new cells in the dentate gyrus of the adult rat hippocampus, strengthens neurodependent long-term potentiation in the hippocampal dentate gyrus, and increases the number of proliferating cells in the prefrontal cortex.