5-hydroxy-6-methoxy (S)-Duloxetine is a metabolite of (S)-duloxetine . It is formed from (S)-duloxetine via a 5- or 6-hydroxy duloxetine intermediate, which is formed by the cytochrome P450 (CYP) isoforms CYP1A2 and CYP2D6, and a catechol duloxetine intermediate. 5-hydroxy-6-methoxy (S)-Duloxetine binds to the serotonin (5-HT), norepinephrine, and dopamine transporters with Ki values of 266, 920, and 2,814 nM, respectively.