1-Formyl-LSD, also known as 1-formyl-N,N-diethyllysergamide and sometimes referred to as 1F-LSD, is a psychedelic drug of the lysergamide family related to lysergic acid diethylamide (LSD).[1][2] It is the 1-formyl derivative of LSD.[1][2][3]

Another drug, 1‐(furan‐2‐carbonyl)‐LSD (SYN-L-005), has also been referred to as "1F-LSD".[3]

Use and effects

The drug is assumed to act as a prodrug of LSD.[1] It produces psychedelic effects in humans similarly to LSD.[2] Effective doses have been reported to be 100 to 150 μg orally or sublingually.[2] Very little is known about the pharmacology and properties of 1-formyl-LSD.[1]

Interactions

History

1-Formyl-LSD was first described in the scientific literature by 2021.[2] It first emerged as a novel designer drug online in January 2019.[1][2]

Society and culture

Canada

1-Formyl-LSD is not an explicitly nor implicitly controlled substance in Canada as of 2025.[4]

United States

1-Formyl-LSD is not an explicitly controlled substance in the United States.[5] However, it could be considered a controlled substance under the Federal Analogue Act if intended for human consumption.

See also

References

  1. 1 2 3 4 5 "1F-LSD". АИПСИН (in Russian). Retrieved 26 July 2025.
  2. 1 2 3 4 5 6 Catalani V, Arillotta D, Corkery JM, Guirguis A, Vento A, Schifano F (9 February 2021). "Identifying New/Emerging Psychoactive Substances at the Time of COVID-19; A Web-Based Approach". Frontiers in Psychiatry. 11 632405. doi:10.3389/fpsyt.2020.632405. ISSN 1664-0640. PMC 7900492. PMID 33633599.
  3. 1 2 Brandt SD, Kavanagh PV, Gare S, Elliott SP, Stratford A, Halberstadt AL (3 December 2024). "Analytical and Pharmacological Characterization of 1-(Furan-2-Carbonyl)-LSD (1F-LSD) and Comparison With 1-(Thiophene-2-Carbonyl)-LSD (1T-LSD)". Drug Testing and Analysis. 17 (8): 1283–1293. doi:10.1002/dta.3829. ISSN 1942-7603. PMC 12319525. PMID 39624022.
  4. "Controlled Drugs and Substances Act". Department of Justice Canada. 5 December 2025. Retrieved 20 January 2026.
  5. Orange Book: List of Controlled Substances and Regulated Chemicals (January 2026) (PDF), United States: U.S. Department of Justice: Drug Enforcement Administration (DEA): Diversion Control Division, January 2026