Antihistamine diphenhydramine showed some antidepressant-like properties. That fact was known at that time. These scientists chose 3-phenoxy-3-phenylpropylamine (a compound structurally similar to diphenhydramine) as terminus a quo. Dozens of its derivatives have been synthesized by Molloy. A selective norepinephrine reuptake inhibitor Nisoxetine became a result of proving the physiological effects of those agents in mice.

Another Eli Lilly scientist, David Wong, trying to discover a derivative inhibiting only serotonin reuptake, suggested that series of laboratory researches dedicated to reuptake of serotonin, norepinephrine and dopamine should be prospected again. In May 1972 Jong-Sir Horng carrying out that test discovered agent which was named later Prozac. It acted as the most potent and effective selective inhibitor of serotonin reuptake of the series.

Lilly scientists claimed Prozac to be the first selective serotonin reuptake inhibitor (SSRI). But they had to issue a correction two years later,where they declared that zimelidine developed by Arvid Carlsson and colleagues had been the first SSRI.

In August 2001 Prozac patent of Eli Lilly expired that induced inflow of generic drugs onto the market. Eli Lilly rebranded Prozac as “Sarafem” for the treatment of premenstrual dysphoric disorder in attempt to reimburse loss caused with reduction of sales of Prozac in Eli Lilly.