This is an unofficial archive of PsychonautWiki as of 2025-08-08T03:33:20Z. Content on this page may be outdated, incomplete, or inaccurate. Please refer to the original page for the most up-to-date information.
WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.
DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.
4-Hydroxy-N-methyl-N-propyltryptamine (also known as 4-HO-MPT or Meprocin) is a novel synthetic psychedelic substance of the tryptamine chemical class that produces psychedelic effects when administered. It is a closely related structural analog of 4-HO-DMT (Psilocin) and other hallucinogenic tryptamines with powerful psychedelic effects.
Very little data exists about the pharmacological properties, metabolism, and toxicity of 4-HO-MPT. It has been sold online as a research chemical as of 2016.[citation needed] It was synthesised and described by Alexander Shulgin in his 1994 book TiHKAL.[1]
4-HO-MPT, or 4-hydroxy-N,N-methylpropyltryptamine, is a synthetic indole molecule of the tryptamine class. Tryptamines share a core structure comprised of a bicylic indole heterocycle attached at R3 to an amino group via an ethyl side chain. 4-HO-MPT is substituted at R4 of its indole heterocycle with a hydroxyl functional group OH−. It also contains a propyl and ethyl chain bound to the terminal amine RN of its tryptamine backbone (MPT).
Like with most psychedelic tryptamines, 4-HO-MPT is thought to act principally as a 5-HT2Apartial agonist. The psychedelic effects are believed to come from 4-HO-MPT's binding efficacy at the 5-HT2A receptors. However, the role of these interactions and how they result in the psychedelic experience continues to remain elusive.
Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), an open research literature based on anecdotal user reports and the personal analyses of PsychonautWikicontributors. As a result, they should be viewed with a healthy degree of skepticism.
It is also worth noting that these effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects. Likewise, adverse effects become increasingly likely with higher doses and may include addiction, severe injury, or death ☠.
The toxicity and long-term health effects of recreational 4-HO-MPT use do not seem to have been studied in any scientific context and the exact toxic dose is unknown. This is because 4-HO-MPT is a research chemical with very little history of human usage.
Anecdotal evidence from people within the community who have tried it suggests that there are no negative health effects attributed to simply trying the drug by itself at low to moderate doses and using it very sparingly (but nothing can be completely guaranteed). Independent research should always be done to ensure that a combination of two or more substances is safe before consumption.
4-HO-MPT is generally considered not habit-forming and the desire to use it can actually decrease with regular consumption. Like with most psychedelics, it is most often thought to be self-regulating.
Tolerance to the effects of 4-HO-MPT are built almost immediately after ingestion. After that, it takes about 3 days for the tolerance to be reduced to half and 7 days to be back at baseline (in the absence of further consumption). 4-HO-MPT presents cross-tolerance with [[Cross-tolerance::all psychedelics]], meaning that after the consumption of 4-HO-MPT all psychedelics will have a reduced effect.
Dangerous interactions
Warning:Many psychoactive substances that are reasonably safe to use on their own can suddenly become dangerous and even life-threatening when combined with certain other substances. The following list provides some known dangerous interactions (although it is not guaranteed to include all of them).
Always conduct independent research (e.g. Google, DuckDuckGo, PubMed) to ensure that a combination of two or more substances is safe to consume. Some of the listed interactions have been sourced from TripSit.
[[Wikipedia:Lithium_(medication)|DangerousInteraction::Lithium]] - Lithium is commonly prescribed for 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.
"[[UncertainInteraction" contains a listed "[" character as part of the property label and has therefore been classified as invalid.]] - Cannabis may have an unexpectedly strong and unpredictable synergy with the effects of 4-HO-MPT. 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 unintentional overdose.
"[[UnsafeInteraction" contains a listed "[" character as part of the property label and has therefore been classified as invalid.]] - Tramadol is well-documented to lower the seizure threshold[2] and psychedelics may act to trigger seizures in susceptible individuals.[citation needed]
Legality
Due to its relative obscurity, the possession and sale of 4-HO-MPT is unscheduled in most countries.
Germany: 4-HO-MPT is controlled under the NpSG[3] (New Psychoactive Substances Act) as of July 18, 2019.[4] Production and import with the aim to place it on the market, administration to another person, placing it on the market and trading is punishable. Possession is illegal but not punishable.[5][6] The legislator considers it possible that orders of 4-HO-MPT are punishable as an incitement to place it on the market.[7]
Switzerland: 4-HO-MPT is not controlled under Buchstabe A, B, C and D. It could be considered legal.[8]
United Kingdom: 4-HO-MPT is a Class A drug in the United Kingdom as a result of the tryptamine catch-all clause.[9]
United States: 4-HO-MPT is unscheduled in the United States. It may be considered an analogue of psilocin (4-HO-DMT) which is a Schedule I drug under the Controlled Substances Act. As such, the sale for human consumption or the use for illicit non-medical or industrial intents and purposes could be prosecuted as crimes under the Federal Analogue Act.[citation needed]
↑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. ISSN1556-9039.
↑"Anlage NpSG" (in Deutsch). Bundesamt für Justiz [Federal Office of Justice]. Retrieved December 10, 2019.
