Serotonin 5-HT2A receptor (antagonist / inverse agonist)

Class

5-HT2A inverse agonist

Notes

original target text: Serotonin 5-HT2A receptor | original target text: Serotonin 5-HT2A receptor (agonist)

The serotonin 5-HT2A receptor is a G protein-coupled receptor found throughout the cerebral cortex, particularly in layers associated with sensory processing and thought organization, as well as on platelets and vascular smooth muscle outside the brain. It is one of the principal receptors through which serotonin shapes cortical excitability, and its overactivation has been linked to perceptual disturbances such as hallucinations and delusions, as well as to disrupted sleep architecture. Blocking this receptor, either as a neutral antagonist or as an inverse agonist (a compound that suppresses baseline receptor signaling even in the absence of serotonin), dampens this cortical signaling without broadly sedating the brain. This rationale underlies interest in 5-HT2A-selective compounds for conditions such as psychosis associated with neurodegenerative disease, negative symptoms of schizophrenia, and sleep disturbance, where older antipsychotics that block dopamine receptors broadly often carry a heavier burden of motor and metabolic side effects. Because 5-HT2A antagonism does not depend on dopamine blockade, it offers a mechanistically distinct route to managing hallucinations and delusions while potentially sparing the motor system. The approach is used across several drug classes, from selective small molecules to agents with broader serotonergic activity, reflecting ongoing efforts to isolate the therapeutic benefit of 5-HT2A modulation from off-target effects.