|Summary sheet: 1P-LSD|
|Substitutive name||1-Propionyl-d-lysergic acid diethylamide|
|Routes of Administration|
1-Propionyl-d-lysergic acid diethylamide (also known as 1P-LSD) is a novel semi-synthetic psychedelic substance of the lysergamide class. 1P-LSD is closely related to LSD and is reported to produce near-identical effects. Little is known about the pharmacology of 1P-LSD, but it likely produces its psychedelic effects by acting on serotonin receptors in the brain.
The original synthesis date of 1P-LSD is unknown. Unlike most research chemicals, 1P-LSD has no record in the scientific literature before its emergence on the online research chemical market in 2015. It was marketed as a legal alternative to LSD alongside other novel lysergamides like ALD-52, ETH-LAD, and AL-LAD.
Subjective effects include geometric visual hallucinations, time distortion, enhanced introspection, conceptual thinking, euphoria, and ego loss. User reports indicate that the subjective effects of 1P-LSD are extremely similar to those of LSD. 1P-LSD is theorized to act as a prodrug for LSD. This hypothesis is supported by the results of a study, showing 1P-LSD is metabolized to LSD in rats. This predicts a near-identical effect profile, likely differing mainly in its rate of absorption and duration. Its classical psychedelic effects and favorable tolerability has led it to become popular among novel psychoactive substance users who use it interchangeably with LSD.
Very little data exists about the pharmacological properties, metabolism, and toxicity of 1P-LSD. It is presumed to have a similar toxicity and risk profile as LSD, although there are no formal studies that prove this. It is highly advised to use harm reduction practices if using this substance.
History and culture
1P-LSD first appeared on the online research chemical market in January 2015. Although it was likely discovered in an academic setting, it is unknown who first synthesized 1P-LSD, as the substance does not appear in any academic literature pre-dating its arrival on the research chemical market. Interestingly, the future usage of 1-akylated lysergamide derivatives as a means to bypass controlled substance laws banning LSD as a precursor was foreseen in a DEA report from 1988:
|“||...a reduction in hallucinogenic activity may become acceptable to the U.S. clandestine chemist when he notes that lysergic acid amide is listed as a Schedule III substance in the CFR; therefore, structurally similar substances of this compound are exempted from the CsA amendment. A lucid argument can then be made that lysergic acid N,N-dimethylamide is derived from lysergic acid amide rather than LSD. Carrying this theme to the next logical step one would then assume that the 1-alkyl and 1-acyl derivatives of the N,N-dimethyl isomer would also not be controlled by the CsA amendment.||”|
|— Donald A. Cooper, Future Synthetic Drugs of Abuse, 1988.|
1P-LSD is a semisynthetic compound of the lysergamide family. It is similar to LSD and is named for the propionyl group bound to the nitrogen of the polycyclic indole group of LSD. Propionyl consists of the carbonyl chain CH3CH2CO- bound to an amino group. 1P-LSD is homologous to ALD-52, which holds an acetyl group bound to the nitrogen instead of the propionyl group bound at the same location. The structure of 1P-LSD contains a polycyclic group featuring a bicyclic hexahydro indole bound to a bicyclic quinoline group. At carbon 8 of the quinoline, an N,N-diethyl carboxamide is bound.
Based on its structural similarity to LSD, 1P-LSD likely acts as a partial agonist at the 5-HT2A receptor. The psychedelic effects are thought to primarily come from its efficacy at the 5-HT2A receptors distributed throughout the brain. 1P-LSD also likely displays binding activity at a wide range of monoamine receptors, such as those for dopamine and norepinephrine. However, there is currently no data to support these claims.
It has been theorized that 1P-LSD may act as a prodrug for LSD. While 1P-LSD shows only 38% the potency of LSD in mice, LSD is detected via LC-MS when 1P-LSD is incubated in human serum. Follow-up studies are currently being conducted to compare the affinity and selectivity of LSD and 1P-LSD at 5-HT receptors, and to determine whether 1P-LSD is hydrolyzed to LSD in vivo. Otherwise, it is possible that 1P-LSD may be capable of exerting its own psychedelic effect.
Prior to the publishing of the above-cited research, medicinal chemist and psychedelic researcher David E. Nichols reportedly commented on the potential 1P-LSD serotonin receptor binding dynamics in private correspondence:
|“||I am sure that the 1-propionyl would also hydrolyze off of an indole, but I don't know whether in vivo conditions would work. In a chemistry lab, you can get off an N-benzoyl, so an N-propionyl will probably come off too. But in the body? I don't know the answer to that. The compound would not be active as the N-propionyl however. The way that LSD docks into the 5-HT2A receptor, the indole NH hydrogen bonds to serine 5.46. With the propionyl, it won't fit into the receptor.||”|
|— David E. Nichols.|
A 2020 study on two human male volunteers found that the levels of 1P-LSD in the serum after administration quickly diminished within the first hour while LSD has been found consistently during the experiment, which further supports the prodrug theory. The study also found that LSD's bioavailability after oral ingestion of 1P-LSD was close to 100%.
Anecdotal reports from many users suggest that the subjective effects of 1P-LSD are so similar to that of LSD so as to be virtually indistinguishable from one another. In comparison to other psychedelics such as psilocybin, LSA and ayahuasca, 1P-LSD is significantly more stimulating and fast-paced regarding the specific style of its physical and cognitive effects.
Disclaimer: The effects listed below are cited from the Subjective Effect Index (SEI), which relies on assorted anecdotal reports and the personal experiences of PsychonautWiki contributors. As a result, they should be taken with a healthy amount of skepticism. It is worth noting that these effects will not necessarily occur in a consistent or reliable manner, although higher doses (common+) are more likely to induce the full spectrum of reported effects. Likewise, adverse effects become much more likely on higher doses and may include serious injury or death.
- Stimulation - 1P-LSD is usually regarded as very energetic and stimulating without being forced. For example, when taken in any environment it will usually encourage physical activities such as running, walking, climbing or dancing. In comparison, other more commonly used psychedelics such as psilocybin which are generally sedating and relaxed.
- Spontaneous bodily sensations - The "body high" of 1P-LSD can be characterized as proportionally very intense in comparison to its accompanying visual and cognitive effects. It behaves as a euphoric, fast-moving, sharp and location-specific tingling sensation. For some, it is manifested spontaneously at different, unpredictable points throughout the trip, but for most, it maintains a steady presence that rises with the onset and hits its limit once the peak has been reached. At moderate to high doses of 1P-LSD, this sensation often approaches its highest level and can become so overwhelming that people may find themselves debilitated with pleasurable sensations.
- Tactile enhancement - Feelings of enhanced tactile sensations are consistently present at moderate levels throughout most 1P-LSD experiences. If level 8A geometry is reached, an intense sensation of suddenly becoming aware of and being able to feel every single nerve ending across a person's entire body all at once is consistently present.
- Stamina enhancement - This is generally mild in comparison to the stamina enhancement produced by traditional stimulants.
- Appetite suppression
- Bodily control enhancement
- Difficulty urinating
- Excessive yawning - This effect is significantly less pronounced than it is with psilocybin and its related compounds, the four-position substituted tryptamines.
- Nausea - Mild nausea is occasionally reported when consumed in moderate to high dosages and either passes instantly soon after the user has vomited or gradually fades by itself as the peak sets in.
- Increased blood pressure
- Increased heart rate
- Increased perspiration
- Muscle contractions
- Muscle spasms
- Pupil dilation
- Increased salivation
- Vasoconstriction - Vasoconstriction may lead to users feeling cold, especially in the extremities.
- Seizure - The likelihood is largely extrapolated from the seizures that have been reported from the use of LSD. It is thought to mainly be a risk in those who are genetically predisposed to them, particularly while accompanied by physically taxing conditions such as states of dehydration, fatigue, undernourishment or overheating.
- Colour enhancement - In comparison to other psychedelics, this effect is often reported to be brighter but not as varied in its character.
- Pattern recognition enhancement
- Visual acuity enhancement
- Drifting (melting, breathing, morphing and flowing) - In comparison to other psychedelics, this effect can be described as highly detailed yet cartoon-like in its appearance. The distortions are slow and smooth in motion and fleeting in their appearance.
- Colour shifting
- Colour tinting
- After images
- Depth perception distortions
- Perspective distortions
- Symmetrical texture repetition
- Scenery slicing
The visual geometry of 1P-LSD can be described as more similar in appearance to that of 2C-B or 2C-I than psilocin, LSA or DMT. It can be comprehensively described through its variations as primarily intricate in complexity, algorithmic in form, unstructured in organization, brightly lit, colourful in scheme, synthetic in feel, multicoloured in scheme, flat in shading, sharp in edges, large in size, fast in speed, smooth in motion, angular in its corners, non-immersive in-depth and consistent in intensity.
1P-LSD is capable of producing a full range of hallucinatory states in a fashion that is significantly less consistent and reproducible than that of many other commonly used psychedelics, specifically tryptamines like DMT or psilocybin mushrooms. These effects include:
- Machinescapes - This component is a rare effect that typically only occurs at very strong to heavy doses, and not as consistently as with notably visual psychedelics like DMT, ETH-LAD, and 2C-P, and atypical psychedelics like salvia.
- Internal hallucination (autonomous entities; settings, sceneries, and landscapes; perspective hallucinations and scenarios and plots) - Although 1P-LSD is technically capable of producing hallucinatory states in a fashion that is on par with psilocin or DMT in its vividness and intensity, these effects are incredibly rare and inconsistent in comparison. While traditional psychedelics such as LSA, ayahuasca and mescaline will induce internal hallucinations near consistently at level 5 geometry and above, 1P-LSD will for most simply go straight into Level 8A visual geometry. This lack of consistently induced hallucinatory breakthroughs means that for most, LSD is limited in depth. When they do occur, they can be described in terms of their variations as lucid in believability, interactive in style, new experiences in content, autonomous in controllability and geometry-based in appearance.
- External hallucination (autonomous entities; settings, sceneries, and landscapes; perspective hallucinations and scenarios and plots)
- Analysis enhancement - This effect is consistent in its manifestation and introspection dominant.
- Anxiety & Paranoia - This effect is not as common at low to moderate doses and is less likely to occur when the basic rules of set and setting are taken into account. It should be noted that this inconsistently induced effect is seemingly more likely to manifest when used with cannabis. This combination should be used with extreme caution if one is not experienced with psychedelics, meaning that the user should adequately pace themselves with a fraction of their usual amount. It is commonly reported that psychedelics can to a certain extent counteract some of the perceived mental cloudiness or intoxicating effects of THC causing the user to in turn use more cannabis than is needed which can often lead to an overwhelmingly anxious headspace or a "bad trip".
- Conceptual thinking
- Creativity enhancement
- Emotion enhancement
- Novelty enhancement
- Personal bias suppression
- Personal meaning enhancement
- Focus enhancement - This effect is experienced exclusively on low or threshold dosages and feels less forced than it does with stimulants.
- Immersion enhancement
- Suggestibility enhancement
- Cognitive euphoria - This component is, generally speaking less consistent and pronounced than it is with substances like psilocybin and MDMA. The mental euphoria experienced on LSD is usually simply due to an enhancement of the user’s current psychological and emotional state coupled with its more regularly occurring effect, physical euphoria.
- Déjà vu
- Increased libido
- Increased music appreciation
- Increased sense of humor
- Memory suppression
- Thought acceleration
- Thought disorganization
- Thought loops
- Time distortion
- Synaesthesia - In its fullest manifestation, this is a very rare and non-reproducible effect. Increasing the dosage can increase the likelihood of this occurring, but seems to only be a prominent part of the experience among those who are already predisposed to synaesthetic states.
- Alcohol - Alcohol's central depressant effects can be used to reduce some of the anxiety and tension produced by 1P-LSD. However, alcohol can cause dehydration, nausea and physical fatigue which can negatively impact the direction of the trip. Users are advised to pace themselves and drink a portion of their usual amount.
- Benzodiazepines - Benzodiazepines are highly effective at reducing the intensity of 1P-LSD's effects through the general suppression of brain activity.
- Cannabis - Cannabis strongly intensifies the sensory and cognitive effects of 1P-LSD. Extreme caution is advised when using this combination as it can significantly increase the chances of a negative psychological reaction like anxiety, confusion and psychosis. Users are advised to start off with only a fraction of their usual cannabis dose and take long breaks between hits to avoid over intake.
- Dissociatives - 1P-LSD enhances the cognitive, visual and general hallucinatory effects of dissociatives. Dissociative-induced holes, spaces, and voids and internal hallucinations become more vivid and intense on 1P-LSD. These effects correspond with an increased risk of confusion, delusions, and psychosis.
- MDMA - 1P-LSD and MDMA are highly synergistic and mutually enhance each other's physical, cognitive, and visual effects. The synergy between these substances is unpredictable, and it is advised to start with markedly lower doses than one would take for each individually. There is some evidence that suggests LSD increases the neurotoxicity of MDMA, which may be relevant to 1P-LSD as well.
Anecdotal reports which describe the effects of this compound within our experience index include:
- Experience: 1 tab 1P-LSD (oral) - Finding myself within the forest
- Experience: 200µg 1P-LSD (sublingual) + 12mg CBD - The Vortex of Empathy
- Experience: 200μg 1P-LSD (oral) - Blissful Paradise
- Experience: 22mg 2C-B (oral) / 100ug 1P-LSD (sublingual) - My first time tripping alone (2 days in a row)
- Experience:100ug 1P-LSD (Oral) + Cannabis - Self Realizations
- Experience:100ug 1P-LSD - A Fear and loathing into Bliss
- Experience:1P-LSD (500ug, tabs) - Infinite Unity
- Experience:300ug 1P-LSD (Oral) - Rainbow Tubes and Becoming One With Humanity
- Experience:300ug 1P-LSD - Living in a simulation filled with love
- Experience:300μg 1P-LSD + 40mg diphenidine - My first psychotic break
Additional experience reports can be found here:
Toxicity and harm potential
The toxicity and long-term health effects of recreational 1P-LSD use have not been studied. This is because 1P-LSD is a research chemical with almost no history of human use.
Anecdotal reports suggest that there are no negative health effects attributed to simply trying 1P-LSD by itself, at low to moderate doses, and using it very sparingly (although nothing can be completely guaranteed). Independent research should always be conducted to ensure that a combination of two or more substances is safe before consumption.
Based on its similarity to LSD, 1P-LSD is assumed to be physiologically well-tolerated with a extremely low toxicity relative to dose. There are relatively few physical side effects that have been reported following acute 1P-LSD exposure.
However, as with LSD and psychedelics in general, it is likely that 1P-LSD can act as a trigger for those with underlying mental disorders. Those with a personal or family history of mental illness are generally advised not to use this substance, particularly when outside of a supervised medical setting.
It is strongly recommended that one uses harm reduction practices when using this substance.
1P-LSD has no known toxic dose. However, higher doses increase the risk of adverse psychological reactions. These reactions include anxiety, delusions, panic attacks and, more rarely, seizures. Medical attention is usually not needed except in the case of severe psychotic episodes or the ingestion of fake acid (such as 25i-NBOMe or DOB). Administration of benzodiazepines or antipsychotics can help to relieve the acute negative cognitive effects of 1P-LSD.
Dependence and abuse potential
Although no formal studies have been conducted, it is assumed that like LSD itself, 1P-LSD is non-addictive with a low abuse potential. There are no literature reports of successful attempts to train animals to self-administer LSD — an animal model predictive of abuse liability — indicating that it does not have the necessary pharmacology to either initiate or maintain dependence. Likewise, there is virtually no withdrawal syndrome when chronic use of LSD is stopped. It is assumed that 1P-LSD shares these properties with LSD.
Tolerance to the effects of 1P-LSD are built almost immediately after ingestion. After that, it takes about 5-7 days for the tolerance to be reduced to half and 14 days to be back at baseline (in the absence of further consumption). 1P-LSD produces cross-tolerance with all psychedelics, meaning that after the use of 1P-LSD they will have a reduced effect.
Although many psychoactive substances are reasonably safe to use on their own, they can quickly become dangerous or even life-threatening when combined with other substances. The list below includes some known dangerous combinations (although it cannot be guaranteed to include all of them). Independent research (e.g. Google, DuckDuckGo) should always be conducted to ensure that a combination of two or more substances is safe to consume. Some interactions listed have been sourced from TripSit.
The following substances are listed on the assumption that 1P-LSD possesses a similar if not the same dangerous interactions profile as LSD, and may include more due to its status as an unstudied research chemical.
- Lithium - Lithium is commonly prescribed in the treatment of bipolar disorder. There is a large body of anecdotal evidence that suggests taking it with psychedelics significantly increases the risk of psychosis and seizures. As a result, this combination is strictly discouraged.
- Cannabis - Cannabis has an unexpectedly strong and unpredictable synergy with the effects of psychedelics. Caution is advised with this combination as it can significantly increase the risk of adverse psychological reactions like anxiety, paranoia, panic attacks, and psychosis. Users are advised to start off with only a fraction of their normal cannabis dose and take long breaks between hits to avoid over intake.
- Stimulants (Amphetamine, cocaine, methylphenidate, ...) - Stimulants affect many parts of the brain and alter dopaminergic function. Combined with psychedelics, stimulation can turn into severe anxiety, panic, thought loops, and paranoia. This interaction may result in an elevated risk of mania and psychosis.
- Tramadol - Tramadol lowers the seizure threshold and psychedelics may act as triggers for seizures in susceptible individuals.
1P-LSD is not scheduled under the UN Convention on Psychotropic Substances. It is considered to exist in a legal grey area in many countries, meaning that while it is not specifically illegal, individuals may still be charged for its possession under certain circumstances such as under analogue laws and with the intent to sell or consume.
- Austria: 1P-LSD is technically not illegal but it may fall in the NPSG (Neue-Psychoaktive-Substanzen-Gesetz Österreich) as an analogue of LSD, thus making it illegal to supply for human consumption.
- Denmark: As of August 25, 2015, 1P-LSD is specifically named on the list of illegal substances.
- Germany: 1P-LSD is controlled under the NpSG (New Psychoactive Substances Act) as of July 18, 2019. Production and import with the aim to place it on the market, administration to another person and trading is punishable. Possession is illegal but not penalized.
- Latvia: 1P-LSD is illegal in Latvia. Although it is not officially scheduled, it is controlled as an LSD structural analog due to an amendment made on June 1, 2015.
- Lithuania: 1P-LSD is illegal in Lithuania and is specifically named on the list of illegal substances since September 21, 2015.
- Sweden: Following its sale as a designer drug, 1P-LSD was made illegal in Sweden on January 26, 2016.
- Switzerland: 1P-LSD is a controlled substance specifically named under Verzeichnis E. It is illegal as of December 2015.
- Turkey: 1P-LSD is illegal in Turkey as of February 2016.
- United Kingdom: 1P-LSD is illegal to produce, supply, or import under the Psychoactive Substance Act, which came into effect on May 26, 2016.
- United States: Since 1P-LSD can be considered a prodrug for LSD, its possession and sale may be prosecutable in the United States under the Federal Analogue Act.
- Brandt, S. D., Kavanagh, P. V., Westphal, F., Stratford, A., Elliott, S. P., Hoang, K., ... & Halberstadt, A. L. (2016). Return of the lysergamides. Part I: Analytical and behavioural characterization of 1‐propionyl‐d‐lysergic acid diethylamide (1P‐LSD). Drug Testing and Analysis, 8(9), 891-902. https://doi.org/10.1002/dta.1884
- Passie, T., Halpern, J. H., Stichtenoth, D. O., Emrich, H. M., & Hintzen, A. (2008). The Pharmacology of Lysergic Acid Diethylamide: A Review, 14, 295–314. https://doi.org/10.1111/j.1755-5949.2008.00059.x
- Carhart-Harris, R. L., Muthukumaraswamy, S., Roseman, L., Kaelen, M., Droog, W., Murphy, K., … Nutt, D. J. (2016). Neural correlates of the LSD experience revealed by multimodal neuroimaging. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.1518377113
- "1P-LSD". Google Trends. Retrieved January 1, 2020.
- Wagmann, Lea; Richter, Lilian H. J.; Kehl, Tobias; Wack, Franziska; Pettersson Bergstrand, Madeleine; Brandt, Simon D.; Stratford, Alexander; Maurer, Hans H.; Meyer, Markus R. (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. doi:10.1007/s00216-018-1558-9. ISSN 1618-2642.
- Brandt, S. D.; Kavanagh, P. V.; Westphal, F.; Stratford, A.; Elliott, S. P.; Hoang, K.; Wallach, J.; Halberstadt, A. L. (2015). "Return of the lysergamides. Part I: Analytical and behavioural characterization of 1‐propionyl‐d‐lysergic acid diethylamide (1P‐LSD)". Drug Testing and Analysis. 8 (9): 891–902. doi:10.1002/dta.1884. ISSN 1942-7603.
- Cooper, Donald A. (1988). "Future Synthetic Drugs of Abuse". Proceedings of the international symposium on the forensic aspects of controlled substances. p. 79. ISBN 978-0-93211-509-6.
- "Kman1898" (January 13, 2015). "The Big & Dandy 1P-LSD Thread, Volume 1". Bluelight.org. Retrieved January 1, 2020.
- Grumann, C.; Henkel, K; Brandt, S. D.; Stratford, A.; Passie, T.; Auwärter, V. (May 15, 2020). "Pharmacokinetics and subjective effects of 1P-LSD in humans after oral and intravenous administration". Drug Testing and Analysis: 1–10. doi:10.1002/dta.2821. eISSN 1942-7611. ISSN 1942-7603. OCLC 231680670. PMID 32415750 Check
- Armstrong, B. D.; Paik, E.; Chhith, S.; Lelievre, V.; Waschek, J. A.; Howard, S. G. (2004). "Potentiation of (DL)‐3,4‐methylenedioxymethamphetamine (MDMA)‐induced toxicity by the serotonin 2A receptior partial agonist d‐lysergic acid diethylamide (LSD), and the protection of same by the serotonin 2A/2C receptor antagonist MDL 11,939". Neuroscience Research Communications. 35 (2): 83–95. doi:10.1002/nrc.20023. ISSN 1520-6769.
- Gudelsky, Gary A.; Yamamoto, Bryan; Nash, J. Frank (1994). "Potentiation of 3,4-methylenedioxymethamphetamine-induced dopamine release and serotonin neurotoxicity by 5-HT2 receptor agonists". European Journal of Pharmacology. 264 (3): 325–330. doi:10.1016/0014-2999(94)90669-6. ISSN 0014-2999.
- Capela, J. P.; Fernandes, E.; Remião, F.; Bastos, M. L.; Meisel, A.; Carvalho, F. (2007). "Ecstasy induces apoptosis via 5-HT2A-receptor stimulation in cortical neurons". Neurotoxicology. 28 (4): 868–875. doi:10.1016/j.neuro.2007.04.005. ISSN 0161-813X. PMID 17572501.
- Nichols, David E. (2004). "Hallucinogens". Pharmacology & Therapeutics. 101 (2): 131–181. doi:10.1016/j.pharmthera.2003.11.002. ISSN 0163-7258.
- Talaie, H.; Panahandeh, R.; Fayaznouri, M. R.; Asadi, Z.; Abdollahi, M. (2009). "Dose-independent occurrence of seizure with tramadol". Journal of Medical Toxicology. 5 (2): 63–67. doi:10.1007/BF03161089. ISSN 1556-9039.
- "Synthetische Drogen: Neues Gesetz soll "Legal Highs" bekämpfen" [Synthetic drugs: New law is to combat legal highs] (in German). Der Standard. September 28, 2011. Retrieved January 1, 2020.
- "Entwurf: Bundesgesetz, mit dem ein Bundesgesetz über den Schutz vor Gesundheitsgefahren im Zusammenhang mit Neuen Psychoaktiven Substanzen (Neue-Psychoaktive-Substanzen-Gesetz, NPSG) erlassen und das Suchtmittelgesetz (SMG) geändert wird" (PDF) (in German). Retrieved January 1, 2020.
- "Bekendtgørelse om euforiserende stoffer - ni nye stoffer tilføjet" (in Danish). Danish Medicines Ageny. August 31, 2015. Retrieved January 1, 2020.
- "Anlage NpSG" (in German). Bundesministerium der Justiz und für Verbraucherschutz [Federal Ministry of Justice and Consumer Protection]. Retrieved December 10, 2019.
- "Verordnung zur Änderung der Anlage des Neue-psychoaktive-Stoffe-Gesetzes und von Anlagen des Betäubungsmittelgesetzes" (PDF). Bundesgesetzblatt Jahrgang 2019 Teil I Nr. 27 (in German). Bundesanzeiger Verlag. July 17, 2019. pp. 1083–1094. Retrieved January 1, 2020.
- "§ 4 NpSG" (in German). Bundesministerium der Justiz und für Verbraucherschutz [Federal Ministry of Justice and Consumer Protection]. Retrieved December 10, 2019.
- "Noteikumi par Latvijā kontrolējamajām narkotiskajām vielām, psihotropajām vielām un prekursoriem" (in Latvian). VSIA Latvijas Vēstnesis. November 10, 2005. Retrieved January 1, 2020.
- "LR SAM Įsakymas Dėl Narkotinių ir psichotropinių medžiagų sąrašų patvirtinimo" (in Lithuanian). Retrieved January 1, 2020.
- "31 nya substanser klassas som narkotika eller hälsofarlig vara" (in Swedish). Folkhälsomyndigheten [Public Health Agency of Sweden]. January 26, 2016. Retrieved January 1, 2020.
- "Verordnung des EDI über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien" (in German). Bundeskanzlei [Federal Chancellery of Switzerland]. Retrieved January 1, 2020.
- "Karar Sayısı : 2016/8548" (PDF) (in Turkish). Resmi Gazete. Retrieved January 15, 2020.
- "Psychoactive Substances Act 2016". UK Government. Retrieved January 1, 2020.
- "Introduction to the Federal Controlled Substance Analogue Act". Erowid. January 2001. Retrieved January 1, 2020.