Pimavanserin is a newly released non-dopaminergic anti-psychotic highly selective for 5-HT2A.
In theory, would such properties treat or exacerbate serotonin toxicity?
My theory is that if you block certain serotonin receptors, there will be more serotonin available to bind to other serotonin receptors, like for example 5-HT1A pre- or post-synaptic, or 5-HT3 receptors.
At a high dose, pimavanserin causes nausea and vomiting, something that blocking 5-HT3 receptors antagonises. I expect there becomes more serotonin to activate 5-HT3 which is anxiogenic and induces nausea/vomiting.
Also, selective 5-HT3 antagonists such as Ondansetron have been proven to worsen or help to cause serotonin syndrome, presumably because blockade allows free serotonin to activate other receptors such as 5-HT2A.
Is this accurate or am I way off here?