Version October 2024
| Drug | Time to peak serum concentration (Tmax) | Elimination half-life (parent drug, unless noted)* | Metabolism¶ | Active metabolites | Protein binding |
| Citalopram | 4 hours | 35 hours | Liver (CYPs 2C19, 2D6, 3A4) | Desmethylcitalopram, didesmethylcitalopram (weakly active) | 80% |
| Escitalopram | 5 hours | 27 to 32 hours | Liver (CYPs 2C19, 2D6, 3A4) | S-desmethylcitalopram, S-didesmethylcitalopram (weakly active) | 56% |
| Fluoxetine | 6 to 8 hours | Parent: 2 to 6 days Metabolite: 7 to 10 days | Liver (CYPs 1A2, 2B6, 2C19, 2C9, 2D6, 2E1, 3A4) | Norfluoxetine | 94.5% |
| Fluvoxamine | 3 to 8 hours | 14 to 16 hours | Liver (CYPs 1A2, 2D6) | None | 80% |
| Paroxetine | IR: 5.2 to 8.1 hours CR: 6 to 10 hours | 15 to 21 hours | Liver (CYP2D6) | None | 95% |
| Sertraline | 4.5 to 8.4 hours | Parent: 26 hours Metabolite: 62 to 104 hours | Liver (CYPs 2B6, 2C19, 2C9, 2D6, 3A4) | Desmethylsertraline (weakly active) | 98% |
CR: controlled-release; CYP: cytochrome P450; IR: immediate-release; SSRI: selective serotonin reuptake inhibitor.
* Elimination half-life may be prolonged in patients with liver impairment, older adults, and with chronic use. During overdose, elimination time may also be prolonged due to saturation of metabolic enzymes and delayed absorption.
¶ CYP isoenzymes in bold indicate a major metabolic pathway of the SSRI.Do you want to add Medilib to your home screen?
