Fluoxetine hydrochloride discovery of fluoxetine began at Eli Lilly in 1970 as a collaboration between Bryan Molloy and Robert Rathbun. Testing the physiological effects of these compounds in mice resulted in nisoxetine, a selective norepinephrine reuptake inhibitor currently widely used in biochemical experiments. This test which carried out by Jong-Sir Horng in May 1972, showed the compound later named fluoxetine to be the most strong and selective inhibitor of serotonin reuptake of the series. Two years later they had to issue a correction, admitting that the first SSRI was zimelidine developed by Arvid Carlsson and colleagues. In 1986, Fluoxetine made its appearance on the Belgian market and was approved for use by the FDA in the United States in December 1987. Fluoxetine was the fourth SSRI to make it to market, after zimelidine, indalpine and fluvoxamine.