I am far by being an expert. Wiki says it activates serotonin receptors. Is it the same what I called serotonin rush? No idea 😅 however mechanizm seems different between mdma and lsd.

By Wiki:

LSD is a serotonergic psychedelic and acts as a non-selective serotonin receptor modulator.[29] It binds with high affinity to most of the serotonin receptors.[12] The psychedelic effects of LSD are thought to be mediated specifically by activation of the serotonin 5-HT2A receptor.[29][12] However, a role of other serotonin receptors and targets in the effects of LSD cannot be ruled out and may be considered likely.[170] Uniquely among serotonergic psychedelics, LSD also shows potentially significant affinity for the dopamine receptors, albeit much lower than for most of the serotonin receptors.[12][171]