elevates Serotonin in Dorsal Raphe Nuclei and causes activation of 5-HT1A
Receptors. This causes a decrease in firing of the serotonergic receptors. Meanwhile SSRIs increase serotonin release in the forebrain. The combination of decreased firing and increase release is canceled out acutely.
eventually cell bodies in the Dorsal Raphe Nuclei are normalized and normal firing resumes. Now, the SSRI can act in the forebrain unimpeded and increases the release of biogenic amines.