askchapo

Collection of papers, summarised on ketamine + Antidepressant (incl. SSRI) interaction (or lack of, I haven't done the reading. Go figure.)

https://psychedelics.ucsf.edu/blog/interactions-between-ketamine-and-prescription-antidepressants

Selective serotonin reuptake inhibitors (SSRIs)

No concerning interactions exist - clinical trials have shown ketamine’s safety and efficacy in patient populations concurrently using escitalopram and sertraline[3][4]. Combination treatment may confer synergistic effects, as demonstrated by a clinical trial comparing escitalopram + ketamine v. escitalopram + placebo for major depressive disorder (MDD), in which ketamine was found to augment the therapeutic efficacy of the SSRI with improvement in suicidality[5]. Another trial on sertraline also suggests that ketamine may be used as adjuvant therapy[6]. However, it’s important to note that ketamine is metabolized by the liver enzymes P450 CYP2B6 and CYP3A4 primarily, so any inhibitors and inducers of these enzymes could alter the metabolism of ketamine. Paroxetine, sertraline, fluoxetine, and fluvoxamine are all CYP3A4 inhibitors, so concurrent use of ketamine can possibly elevate the bioavailability of ketamine. However, this slight elevation may not be clinically significant[7][8].