Effects of LSD and Psilocybin on Heart Rate in Patients Receiving Psychedelic Treatment for Depressive and Anxiety Disorders: A Retrospective Observational Study
Psychology International December 19, 2025 M Cheng, Tatiana Aboulafia Brakha, Albert Buchard et al.
LSD and psilocybin produce different patterns of heart rate change over time in patients with treatment-resistant depression or anxiety disorders. In a small retrospective study of 30 patients receiving either substance during supervised sessions, LSD caused a delayed but sustained heart rate increase peaking at 3–4 hours, while psilocybin led to an earlier decline. Anxiety levels did not explain these differences, and no serious cardiovascular events occurred. The distinct temporal profiles suggest the two psychedelics may activate the cardiovascular system differently in clinical populations, though the findings are preliminary due to the small sample and retrospective design.