(R)-Norfluoxetine is a pharmacologically active metabolite of Fluoxetine that is a selective serotonin reuptake inhibitor. (R)-Norfluoxetine was being investigated by Eli Lilly and Company for treatment pain and drug abuse, but future development was discontinued.

Seproxetine, also known as (S)-norfluoxetine, is a selective serotonin reuptake inhibitor (SSRI). It is the most important active metabolite of the widely used antidepressant fluoxetine, but little is known about its pharmacological actions. Seproxetine was being investigated by Eli Lilly and Company as an antidepressant; however, a cardiac side effect was noted and development was discontinued.

Norfluoxetine is an active N-desmethyl metabolite of the antidepressant fluoxetine that inhibits serotonin uptake. Norfluoxetine is selective serotonin reuptake inhibitor (SSRI) but little is known about its pharmacological actions. Seproxetine (S- Norfluoxetine) was being investigated by Eli Lilly as an antidepressant but development was never completed and the drug was never marketed.