Psychedelic studies in nonhuman primates: Past and future.
Mol Psychiatry September 12, 2025 Jamie C. Masthay, Alex C. Kwan, Steve W. C. Chang
Research on serotonergic psychedelics in nonhuman primates (NHPs) has revealed that these drugs cause characteristic changes in both spontaneous and operant behaviors, though effects vary across studies due to differences in drugs, doses, and individual responsiveness. Some effects in NHPs mirror those in humans, such as the development of tolerance and low abuse liability, but evidence is mixed on whether psychedelics cause visual hallucinations in NHPs. NHP studies have also helped clarify mechanisms of action, connecting findings from human and rodent research. The review concludes that NHPs have potential as preclinical models for studying psychedelic effects on psychiatric conditions and suggests future research directions.