All about 1Fe-LSD effects at a glance

For 10 years, Germany's drug policy has repeatedly led to a unique situation: no sooner has one LSD alternative disappeared from the market than the next legal LSD derivative emerges: chemically altered, legally reclassified, and still largely unexplored scientifically.

1Fe-LSD is one such novel LSD derivative that is currently attracting attention in the psychonaut community and raising many questions.

In this article, we take a closer look at the chemistry and mechanism of action of the molecule, its possible similarities and differences to LSD-25, and, above all, the special considerations to be observed when handling the research chemical.

Enjoy reading the blog post!

Note: 1Fe-LSD is not intended for human consumption. All described content is based on scientific sources or subjective experience reports and is not to be understood as instructions or recommendations.

1Fe-LSD is a novel LSD derivative that belongs to the group of so-called research chemicals and is structurally based on the well-known lysergic acid diethylamide. It was introduced to the market at the end of 2025 almost simultaneously with 1BP-LSD, after the previous LSD analogs 1SB-LSD and 1S-LSD were banned as part of an NpSG amendment, i.e., a revision of the New Psychoactive Substances Act.

Chemically speaking, 1Fe-LSD is a modified variant of the LSD molecule, in which an additional functional group is bonded to the indole nitrogen, specifically a ferrocenecarbonyl unit. This organometallic structure contains iron and clearly distinguishes 1Fe-LSD from earlier derivatives such as 1P-LSD, 1cP-LSD, or 1D-LSD. This ferrocene group is also responsible for the orange coloration of the 1Fe-LSD blotters and pellets.

Compared to established derivatives, the data on 1Fe-LSD is currently limited, which is why many aspects of its pharmacology and toxicology have not yet been conclusively clarified.

As with all research chemicals, however: 1Fe-LSD is not approved as a medicine and is not intended for human consumption.

Like other LSD analogs, 1Fe-LSD is also discussed as a potential prodrug that could be gradually converted into classic LSD in the body.

An LSD prodrug is a chemically modified precursor to lysergic acid diethylamide (LSD) which itself does not primarily act as an active substance, but is only converted into LSD by metabolic products within the body. The LSD molecule is modified by an additional group that can be enzymatically cleaved during metabolism. Only after this conversion does the pharmacological effect typical of LSD unfold. In 1Fe-LSD, this additional group is the eponymous ferrocene group.

The concept of prodrugs is not unusual in pharmacology and is often used to influence the stability, solubility, or absorption of a substance.

In the case of LSD derivatives, the structural modifications serve as a way to circumvent legal prohibitions and create LSD derivatives that can be legally provided. This principle in the production is called "legal by design".

Due to additional side chains, the effect profile of such LSD derivatives acting as prodrugs theoretically resembles that of classic LSD, even if the onset of action or intensity may differ in nuances.

There is currently only limited scientific data on the biochemical effects of 1Fe-LSD, which is why many assessments are based on structural comparisons with classic lysergamides.

According to current understanding, 1Fe-LSD is classified as a so-called prodrug, meaning it could be enzymatically converted into active LSD in the body. The binding to serotonin receptors, especially the 5-HT2A receptor in the central nervous system, is crucial for the psychedelic effect. This binding causes the typical LSD high, which is widely depicted in popular culture.

This receptor activation modulates neuronal signaling processes, which can lead to altered perception patterns, intensified sensory impressions, novel experiences, an "expanded" consciousness, perceptual disturbances, and an altered self-perception.

Research results on LSD suggest that psychedelic substances influence the functional connectivity of various brain networks and loosen habitual communication patterns in the brain. Psychoactive substances have the ability to improve the so-called neuroplasticity of the brain and could help in the treatment of various diseases. [6]

Whether and to what extent 1Fe-LSD differs in its pharmacokinetics from other LSD derivatives such as 1BP-LSD has not yet been conclusively clarified. The current data therefore primarily emphasizes one thing: it is a substance whose effects have not yet been comprehensively researched scientifically. The currently available information comes mainly from anecdotal accounts, individual experiences, and experience reports from individuals who have experimented with the substance themselves.

Binding to the so-called 5-HT2A receptor in the brain is one of the most important mechanisms for understanding LSD and its analogs.

This specific type of serotonin receptor, when hallucinogens such as LSD, psilocybin, mescaline, or LSD alternatives bind to it [2], causes the typical psychedelic effects.

The neurotransmitter serotonin plays a central role in the brain in regulating mood, drive, and emotional balance, and also influences sleep, appetite, perception processing, and cognitive functions such as learning and memory. [3]

Considering the diverse roles of the tryptamine serotonin in the brain and for the entire organism, it becomes clear why the consumption of LSD (and possibly also LSD derivatives) is viewed with such interest, especially in psychiatric and pharmacological research: psychedelics have the potential to help people with various mental illnesses within the framework of professional therapies and could be an important step in the development of medications. [4, 5, 6]

The side chain with the attached ferrocene in 1Fe-LSD results in a higher molar mass compared to standard LSD-25. This chemical detail is important because it affects the research quantity of the LSD derivative and thus indirectly its effects and dosage in research projects.

Let's look at this in more detail:

LSD-25 has a molar mass of 323.4 g/mol; a 1Fe-LSD molecule has a molar mass of 535.5 g/mol.

This means, converted: To achieve the effect of a 100 µg dose of LSD-25, approximately 165 µg of 1Fe-LSD would be required in research projects. For researchers, 1.65 times the dose of 1Fe-LSD would be needed to achieve an intensity of effect comparable to standard LSD.

Observations suggest that modern LSD derivatives such as 1Fe-LSD or 1BP-LSD exert their effects in the body as so-called prodrugs. This means that they are metabolized in the body into LSD-25 and can cause similar effects to the parent substance developed by Albert Hofmann.

However, reliable scientific data on both LSD derivatives is currently still lacking. Many expectations and assumptions about their effects are therefore based on structural comparisons and theoretical considerations, not on comprehensive clinical studies.

At the same time, a look at the role of serotonin and the 5-HT2A receptor shows why lysergamides generally arouse high research interest – especially in the context of psychiatric questions.

Nevertheless, it should be noted that 1Fe-LSD is a research chemical without approval. The risks and long-term consequences of 1Fe-LSD consumption have not yet been sufficiently investigated.

Anyone dealing with the substance therefore operates in a field between chemical innovation, regulatory dynamics, and scientific uncertainty. This is precisely why a sober, differentiated view of facts, data, experience reports, and legal frameworks is important.

• [1] Passie, T., Halpern, J. H., Stichtenoth, D. O., Emrich, H. M., & Hintzen, A. (2008). The pharmacology of lysergic acid diethylamide: a review. CNS Neuroscience & Therapeutics, 14(4), 295–314. doi: https://doi.org/10.1111/j.1755-5949.2008.00059.x

• [2] De Gregorio D., Aguilar-Valles A., et al. (2021). Hallucinogens in Mental Health: Preclinical and Clinical Studies on LSD, Psilocybin, MDMA, and Ketamine. J Neurosci. 2021 Feb 3;41(5):891-900. doi: 10.1523/JNEUROSCI.1659-20.2020.

• [3] Martí J., Lu H. (2021) Microscopic Interactions of Melatonin, Serotonin and Tryptophan with Zwitterionic Phospholipid Membranes. Int J Mol Sci. 2021 Mar 11;22(6):2842. doi: 10.3390/ijms22062842.

• [4] Galvão-Coelho N.L., Marx W., Gonzalez M., Sinclair J., de Manincor M., Perkins D., Sarris J. (2021). Classic serotonergic psychedelics for mood and depressive symptoms: a meta-analysis of mood disorder patients and healthy participants. Psychopharmacology (Berl). 2021 Feb;238(2):341-354. doi: 10.1007/s00213-020-05719-1.

• [5] Walsh C.A., Gorfinkel L., Shmulewitz D., Stohl M., Hasin D.S. (2024). Use of Lysergic Acid Diethylamide by Major Depression Status. JAMA Psychiatry. 2024 Jan 1;81(1):89-96. doi: 10.1001/jamapsychiatry.2023.3867.

• [6] Mastinu A., Anyanwu M., Carone M., Abate G. et al. (2023). The Bright Side of Psychedelics: Latest Advances and Challenges in Neuropharmacology. Int J Mol Sci. 2023 Jan 10;24(2):1329. doi: 10.3390/ijms24021329.