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4-HO-EPT
4-Hydroxy-N-ethyl-N-propyltryptamine
Eprocin
4-HO-EPT is a synthetic psychedelic of the tryptamine chemical class.1 It is structurally related to psilocin1, the active component of psilocybin mushrooms, and produces similar psychedelic effects. It was encountered as a novel designer drug in Japan by 2021.2
Dosage & Duration
Dosage
Doses are population estimates that vary widely between individuals.
Threshold~10 mg
Light10-20 mg
Moderate20-30 mg
Strong30-50 mg
Heavy50+ mg
Duration
Onset30-60 minutes
Peak1-2 hours
Offset1-2 hours
Total3-7 hours
Subjective Effects
Subjective Effects not written up yet
Pharmacology
Pharmacodynamics
4-HO-EPT acts as a potent full agonist at serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptors. Its agonist potency at 5-HT2A and 5-HT2B is one to two orders of magnitude greater than at 5-HT2C. It also binds to 5-HT1A and 5-HT6 receptors.3 In rodents, it elicits the head-twitch response,4 a behavioral marker used to assess psychedelic activity.4
Pharmacokinetics
Absorption & half-lifenot documented yetMetabolitesnone documented yet
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
Tolerance timelines are rules of thumb, not exact schedules, and vary widely between individuals and use patterns.
Tolerance to the effects of 4-HO-EPT develops almost immediately after ingestion.
Tolerance returns to baseline after approximately 7 days without further use.
Tolerance decreases to approximately half its initial level after 3 days without further use.
All psychedelics
Harm Potential
Addiction & Dependence
Psychological
Higher doses may increase adverse effects, including possible addiction-related concerns, but 4-HO-EPT-specific addiction risk has not been characterized.
Toxicity
The exact toxic dose is described as unknown, and recreational toxicity and long-term health effects are said not to have been scientifically studied.
Nausea is listed among physical effects.
Psychosis Risk
Psychosis risk is specifically warned for lithium combinations and may be increased by cannabis or stimulant combinations; delusion is also listed as a cognitive effect.
Seizure Risk
Lithium is warned to significantly increase psychosis and seizure risk, and tramadol may lower the seizure threshold enough for psychedelics to trigger seizures in susceptible people.
History & Culture
4-HO-EPT was sold online as a research chemical in 2016, with no known history of human use before that time. By 2021, it had been encountered in Japan as a novel designer drug.2 It remained obscure, with use occurring in recreational and research contexts. Alexander Shulgin's book TiHKAL (Tryptamines I Have Known and Loved) did not mention the substance.
Legality
By Country
Illegal4
United StatesIllegal (analog/blanket ban)The federal controlled-substances list does not separately name 4-HO-EPT. Under 21 U.S.C. §§ 802(32) and 813, it may be treated as a Schedule I controlled substance analogue to the extent intended for human consumption if it meets the statutory structural and effects or representation requirements and is not within an exclusion. In that circumstance, 21 U.S.C. §§ 841(a)(1) and 844(a) prohibit unauthorized possession, manufacture, distribution, dispensing, and possession with intent to manufacture, distribute, or dispense. This classification concerns federal law and does not determine its status under state, local, territorial, or tribal law.
GermanyIllegal (analog/blanket ban)4-HO-EPT is covered by the generic indole-3-alkylamine definition in Anlage 1 Nr. 5.1 of the Neue-psychoaktive-Stoffe-Gesetz (NpSG), rather than being individually named. This coverage has applied since 18 July 2019. Subject to statutory exemptions for recognized commercial, industrial, scientific, and specified official uses, § 3 prohibits trade, placing on the market, manufacture, import, export, transit, acquisition, possession, and administration to another person. Under § 4(1), trade, placing on the market, or administration to another person, as well as manufacture or movement into Germany for the purpose of placing the substance on the market, is punishable by imprisonment for up to three years or a fine; attempt is also punishable. Acquisition and possession are prohibited but are not themselves ordinary criminal offences under § 4, although the substance may be seized and destroyed.
SwitzerlandIllegal (analog/blanket ban)Verordnung des EDI vom 30. Mai 2011 über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien (Betäubungsmittelverzeichnisverordnung, BetmVV-EDI), Anhang 6, Verzeichnis e121314151617
4-HO-EPT is covered by the generic Tryptamine entry in Verzeichnis e because its N-ethyl, N-propyl, and 4-hydroxy substituents fit the entry's structural definition. Under BetmKV Article 3(2)(e), Verzeichnis e materials and products are subject to the control measures applicable to Verzeichnis a narcotics; industrial and scientific use are exempt from the generic entry, but private use is not. BetmG Article 20(1)(c) makes unauthorized cultivation, manufacture, import, export, storage, use, or placing on the market of Article 7 substances punishable by up to three years' imprisonment or a monetary penalty.
United KingdomIllegalMisuse of Drugs Act 1971, Schedule 2 Part I paragraph 1(b), as added by the Misuse of Drugs Act 1971 (Modification) Order 197713282930313233343536
4-HO-EPT falls within the generic structural definition added to Schedule 2 Part I paragraph 1(b) of the Misuse of Drugs Act 1971 by the Misuse of Drugs Act 1971 (Modification) Order 1977 and is therefore a Class A controlled drug. This classification has applied since 20 September 1977. The Act prohibits possession, possession with intent to supply, production, supply, offering to supply, import, and export, subject to its licences, regulations, exceptions, and defences.
References
Source Pages
Citations
Further Reading
Article Status
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