LSD administered to pregnant mice reaches the embryonic brain fluid within 15 minutes, causing immediate physical remodeling of the fetal brain.
April 1, 2026
Original Paper
Gestational LSD exposure in mouse rapidly reaches embryonic CSF and is associated with altered choroid plexus signaling, cerebral cortical development, and offspring behavior
bioRxiv · 2025.09.30.677638
The Takeaway
This study provides a high-resolution look at how quickly psychedelics cross the placenta to reach the fetus, revealing that they don't just affect chemistry but trigger rapid structural changes in the interfaces of the developing brain.
From the abstract
Classic serotonergic psychedelics engage 5-HT receptors throughout the nervous system, but how maternal exposure intersects with embryonic brain interfaces is poorly defined. Here we tested in mice whether maternally administered lysergic acid diethylamide (LSD) accesses embryonic cerebrospinal fluid (CSF) and whether embryonic choroid plexus (ChP), a CSF-secreting epithelium enriched for Htr2c, mounts an acute response. Following a single maternal injection (0.3 mg/kg, subcutaneous), LSD was de