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1B-LSD
1-Butanoyl-d-lysergic acid diethylamide
1-butyryl-LSD
1B-LSD is a synthetic psychedelic of the lysergamide class and an acylated derivative of LSD.1 It first appeared on the research chemical market in 2018 and functions as a prodrug for LSD, producing a near-identical effect profile upon metabolism.23 Structurally distinguished by a butanoyl group bound to the nitrogen of LSD's indole system, 1B-LSD is roughly one-seventh the potency of LSD by weight.4
Dosage & Duration
Dosage
Threshold~15 µg
Light15-50 µg
Moderate50-125 µg
Strong125-250 µg
Heavy250+ µg
Duration
Onset20-60 minutes
Come Up45-120 minutes
Peak3-5 hours
Offset3-5 hours
After Effects6-24 hours
Total8-12 hours
Subjective Effects
Effects vary widely by individual, dose, and context.
Physical
Cognitive
In comparison to other psychedelics such as Psilocin, LSA and Ayahuasca, 1B-LSD is significantly more stimulating and fast paced in terms of the specific style of thought stream which it produces and contains a large number of potential effects.
Enhancement of current mind stateAcceleration of thoughtFeelings of fascination, importance and aweTime distortionIntrospectionDeja-VuMultiple thought streamsRemoval of cultural filterConceptual thinkingEgo suppression, loss and deathPersonality regressionThought loopsFeelings of interdependent oppositesDelusionsStates of unity and interconnectedness
Visual
Geometry
The visual geometry of 1B-LSD can be described as more similar in appearance to that of 2C-B and the 2C-x family than psilocin, LSA, or DMT. They can be comprehensively described as unstructured in organization, algorithmic and digital in geometric style, intricate in complexity, large in size, fast and smooth in motion, multicoloured in scheme, bright and flat in colour, and sharp in their edges with extremely angular corners. At higher dosages they consistently result in states of Level 7A visual geometry.
Hallucinatory States
1B-LSD is capable of producing a full range of low and high level hallucinatory states in a fashion that is significantly less consistent and reproducible than that of many other commonly used psychedelics.
Auditory
Adapted from the LSD subjective effects documentation. 1B-LSD is a prodrug of LSD and is reported to produce an effectively identical experience. Forked from Subjective Effect Documentation
by Josie KinsOctober 2012.
by Josie KinsOctober 2012.
Pharmacology
Pharmacodynamics
In recombinant human-receptor assays, 1B-LSD bound several serotonin receptors but was only a weak partial agonist at 5-HT2A in a calcium-mobilization assay (EC50 85 nM; Emax 23% of the serotonin maximum). It showed no agonist activity at 5-HT2B or 5-HT2C in that assay despite binding to both receptors.3
In mice, 1B-LSD produced the 5-HT2A-associated head-twitch response with an ED50 of 976.7 nmol/kg (95% CI 714.8–1335), about 14% of LSD's molar potency in the same comparison. This animal result does not establish human potency or a human dose conversion.34
Pharmacokinetics
In pooled human-liver S9 experiments, 1B-LSD underwent deacylation to LSD. The same study associated oxidative N-dealkylation and hydroxylation across the tested LSD derivatives predominantly with CYP1A2 and CYP3A4; it did not establish that those enzymes catalyze deacylation itself.2 The available evidence is preclinical and in vitro. These studies did not establish controlled human oral bioavailability, time to peak concentration, elimination half-life, or conversion fraction for 1B-LSD.32
Dangerous
Highest riskThese combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.
Unsafe
AvoidThere is considerable risk of physical harm when taking these combinations, they should be avoided where possible.
Caution
Use cautionThese combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.
Tolerance
Full Tolerance
Tolerance to the effects of 1B-LSD develops almost immediately after ingestion.
Baseline Reset
14 days
Half Tolerance
5-7 days
Cross Tolerance
Serotonergic psychedelics
Harm Potential
Addiction & Dependence
Psychological
Extremely LowAssumed to be non-addictive with low abuse potential based on similarity to LSD. Animal self-administration studies with LSD (a model predictive of abuse liability) have consistently failed, indicating the pharmacology does not support initiation or maintenance of dependence.5
Physical
Extremely LowVirtually no withdrawal syndrome is expected when use is stopped, based on comparison to LSD which produces no physical dependence.5
Psychosis Risk
1B-LSD may act as a trigger for psychotic episodes in individuals with underlying mental disorders or a personal or family history of mental illness. Higher doses increase the risk of adverse psychological reactions including delusions. Those predisposed to mental illness are advised not to use this substance outside of supervised medical settings.
Seizure Risk
Seizure risk is largely extrapolated from rare reports associated with LSD use. Seizures are thought to mainly affect those who are genetically predisposed, particularly when accompanied by physically taxing conditions such as dehydration, fatigue, undernourishment, or overheating.6
History & Culture
1B-LSD emerged on the online research chemical market in August 2016, following a pattern common among novel lysergamide derivatives designed to occupy legal grey areas in jurisdictions where LSD itself is controlled.41 The identity of…
Trip Reports
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Legality
International
Not scheduled under the UN Convention on Psychotropic Substances
By Country
United StatesUnscheduled (Federal Analogue Act applies)Citation needed
Not explicitly listed as a controlled substance. However, as a prodrug that metabolizes to LSD, possession and sale may be prosecutable under the Federal Analogue Act when intended for human consumption.17
GermanyIllegalAnlage 1
1B-LSD (1-butyryl-LSD) is covered by Anlage 1's definition of Δ9,10-ergolene derivatives, which includes an alkylcarbonyl group with an alkyl residue of up to four carbons bound through the ergolene nitrogen. The Neue-psychoaktive-Stoffe-Gesetz prohibits acquiring, possessing, manufacturing, trading in, placing on the market, administering, and importing or exporting covered new psychoactive substances, subject to the Act's specified exemptions.
LatviaIllegal (analog/blanket ban)I saraksts — lizergamīdi
Likums “Par Krimināllikuma spēkā stāšanās un piemērošanas kārtību”, 2. pielikums, II nodaļas 11. punkta 21. apakšpunkts (I saraksts), read with Narkotisko un psihotropo vielu un zāļu, kā arī prekursoru likumīgās aprites likums, 3. panta trešās daļas 5. punkts un 5. pants1011
Although not officially scheduled by name, 1B-LSD is controlled as a structural analogue of LSD pursuant to an amendment enacted on June 1, 2015.
NetherlandsIllegalLijst I
Opiumwet12
1B-LSD (1-butyryl-LSD) is prohibited under List I of the Opium Act. List I covers mono- and dialkylamide derivatives of lysergic acid, including products obtained from those derivatives by introducing methyl, acetyl, or halogen groups; 1B-LSD is a butyryl-substituted N,N-diethyllysergamide. The Act prohibits importing or exporting, preparing, processing, selling, supplying, transporting, possessing, and manufacturing List I substances.
SwedenIllegalBilaga 1
Förordning (1992:1554) om kontroll av narkotika, bilaga 115
Prohibited as of January 26, 2016, following its emergence as a designer drug. Sweden's public health agency further recommended classifying it as a hazardous substance on June 24, 2019.
United KingdomIllegal (Psychoactive Substances Act)Citation needed
Prohibited under the Psychoactive Substances Act 2016, which came into effect on May 26, 2016. Production, supply, and importation are criminal offenses.16
AustriaGrey area (NPSG may apply)Citation needed
While not technically illegal by name, 1B-LSD may fall under the Neue-Psychoaktive-Substanzen-Gesetz (NPSG) as a structural analogue of LSD, rendering it illegal to supply for human consumption.
JapanIllegalCitation needed
Controlled under the Pharmaceutical Affairs Law. Both possession and sale are prohibited.9
LithuaniaIllegalCitation needed
Specifically named on the national list of controlled substances since June 5, 2019.
SingaporeIllegalFirst Schedule
Misuse of Drugs Act13
Prohibited under Singapore's controlled substances legislation.14
SwitzerlandControlled (with exceptions)Citation needed
The substance is controlled in Switzerland under Verzeichnis E, point 263, because it is covered as a defined lysergic acid derivative. It remains lawful only for scientific or industrial use.
References
Source Pages
Citations
- Emmanouil Tsochatzis, Joao Alberto Lopes, Fabiano Reniero, Margaret Holland, Jenny Åberg, & Claude Guillou. (February 2020). Identification of 1-Butyl-Lysergic Acid Diethylamide (1B-LSD) in Seized Blotter Paper Using an Integrated Workflow of Analytical Techniques and Chemo-Informatics. Molecules, 25(3), 712. https://doi.org/10.3390/molecules25030712123
- Lea Wagmann, Lilian H. J. Richter, Tobias Kehl, Franziska Wack, Madeleine Pettersson Bergstrand, Simon D. Brandt, Alexander Stratford, Hans H. Maurer, & Markus R. Meyer. (July 2019). In vitro metabolic fate of nine LSD-based new psychoactive substances and their analytical detectability in different urinary screening procedures. Analytical and Bioanalytical Chemistry, 411(19), 4751–4763. https://doi.org/10.1007/s00216-018-1558-9123
- Adam L. Halberstadt, Muhammad Chatha, Adam K. Klein, John D. McCorvy, Markus R. Meyer, Lea Wagmann, Alexander Stratford, & Simon D. Brandt. (August 2020). Pharmacological and biotransformation studies of 1-acyl-substituted derivatives of d-lysergic acid diethylamide (LSD). Neuropharmacology, 172. https://doi.org/10.1016/j.neuropharm.2019.1078561234
- Simon D. Brandt, Pierce V. Kavanagh, Folker Westphal, Alexander Stratford, Simon P. Elliott, Geraldine Dowling, Jason Wallach, & Adam L. Halberstadt. (August 2019). Return of the lysergamides. Part V: Analytical and behavioural characterization of 1-butanoyl-d-lysergic acid diethylamide (1B-LSD). Drug Testing and Analysis, 11(8), 1122–1133. https://doi.org/10.1002/dta.2613123
- Nichols DE. (2016). Psychedelics. Pharmacological Reviews, 68(2), 264-355. https://doi.org/10.1124/pr.115.01147812
- Simonsson O, & Hendricks PS. (2022). Prevalence and associations of classic psychedelic-related seizures in a population-based sample. Drug and Alcohol Dependence. https://doi.org/10.1016/j.drugalcdep.2022.1095121
- Neue-psychoaktive-Stoffe-Gesetz. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/anlage_1.html1
- Neue-psychoaktive-Stoffe-Gesetz. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/__3.html1
- 指定薬物を指定する省令が公布されました. (2021). https://www.mhlw.go.jp/seisakunitsuite/bunya/kenkou_iryou/iyakuhin/yakubuturanyou/oshirase/20200826-1.html1
- Likums “Par Krimināllikuma spēkā stāšanās un piemērošanas kārtību”, 2. pielikums, II nodaļas 11. punkta 21. apakšpunkts (I saraksts), read with Narkotisko un psihotropo vielu un zāļu, kā arī prekursoru likumīgās aprites likums, 3. panta trešās daļas 5. punkts un 5. pants. likumi.lv (n.d.). https://likumi.lv/ta/id/50539-par-kriminallikuma-speka-stasanas-un-piemerosanas-kartibu#piel21
- Likums “Par Krimināllikuma spēkā stāšanās un piemērošanas kārtību”, 2. pielikums, II nodaļas 11. punkta 21. apakšpunkts (I saraksts), read with Narkotisko un psihotropo vielu un zāļu, kā arī prekursoru likumīgās aprites likums, 3. panta trešās daļas 5. punkts un 5. pants. likumi.lv (n.d.). https://likumi.lv/ta/id/40283-par-narkotisko-un-psihotropo-vielu-un-zalu-likumigas-aprites-kartibu1
- Opiumwet. wetten.overheid.nl (n.d.). https://wetten.overheid.nl/BWBR0001941/2025-07-011
- Misuse of Drugs Act. cnb.gov.sg (n.d.). https://www.cnb.gov.sg/mediaroom/news/misuse-of-drug-act-mda/1
- Misuse of Drugs Act (MDA) — Central Narcotics Bureau, Singapore (amendments effective 1 May 2020). sso.agc.gov.sg (n.d.).1
- Förordning (1992:1554) om kontroll av narkotika. riksdagen.se (n.d.). https://www.riksdagen.se/sv/dokument-och-lagar/dokument/svensk-forfattningssamling/forordning-19921554-om-kontroll-av-narkotika_sfs-1992-1554/1
- Psychoactive Substances Act 2016. UK Government (n.d.). https://www.legislation.gov.uk/ukpga/2016/2/contents/enacted1
- 21 U.S. Code § 813 - Treatment of controlled substance analogues. (n.d.). https://www.law.cornell.edu/uscode/text/21/8131
Further Reading
- Halberstadt AL & Geyer MA. Head-twitch response methodology.
Halberstadt AL & Geyer MA. Head-twitch response methodology. Psychopharmacology 2013
PubChem: 145845769- PubChem: CID 145875086
- Reviewed & approved
Reviewed, edited, and approved by subject-matter expert Lyrea.
Automated synthesisInformation aggregated and synthesized using an autonomous workflow built by Josie Kins.
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