I'll start with a quick overview while I pull detailed information from the medical library.

SSRIs (Selective Serotonin Reuptake Inhibitors) are the first-line antidepressants for depression, anxiety disorders, OCD, PTSD, and several other conditions. They work by blocking the serotonin transporter (SERT), increasing synaptic serotonin. Common examples: fluoxetine, sertraline, escitalopram, paroxetine, fluvoxamine, citalopram.

The query "SSRI" is broad. Let me clarify what aspect you need before diving deep.