O-PCE

O-PCE, or 2'-Oxo-PCE, belongs to the arylcyclohexylamine chemical class. Arylcyclohexylamine drugs are named for their structures which include a cyclohexane ring bound to an aromatic ring along with an amine group. Deschloroketamine contains a phenyl ring bonded to a cyclohexane ring substituted with an oxo group (cyclohexanone) at R₁. Bound to the adjacent alpha carbon (R₂) of the cyclohexanone ring is an amino ethyl chain -NCH₂CH₃. 2'-Oxo-PCE, like MXE contains an amino ethyl chain rather than the amino methyl chain found in DCK and ketamine. 2'-Oxo-PCE is homologous to DCK, differing only in the length of their carbon chain.

Due to the lack of research regarding the substance, all discussion regarding the pharmacology of it is purely based on its structure and subjective effect similarities to other arylcyclohexylamine dissociatives such as ketamine, PCE and methoxetamine (3-MeO-2'-Oxo-PCE). While no scientific studies have been conducted to verify this, structure-activity relationship analysis suggests that 2'-Oxo-PCE likely exhibits its observed effects principally as an NMDA receptor antagonist, although other neurotransmitter systems may be involved.^{[citation needed]}

NMDA receptors (a subtype of receptors for glutamate, which are the principle excitatory neurotransmitters in the nervous system) allow for electrical signals to pass between nerve cells in the brain and spinal column; for the signals to pass, the receptor must be open. NMDA receptor antagonists have been shown to disrupt this signaling by blocking these receptors. This disconnection of information flow in the nervous system leads to loss of sensation (anesthesia), difficulty moving (motor discoordination), and eventually this substance's equivalent of the “K-hole.”^{[citation needed]}

In comparison to DCK, ketamine and MXE, this compound can be described as generally more stimulating with fewer cognitive and sensory suppressions. The first half of its duration has been reported to produce primarily stimulating effects with minimal dissociation whilst the second half is primarily dissociating with minimal stimulation.

Users have compared the nature and cognitive effects to MXE specifically, albeit without the pronounced "body warmth" or physical euphoria and a having a tendency of producing rather stimulating and chaotic responses with higher dosages.

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 PsychonautWiki contributors. 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 ☠.

Experience reports

There are currently no anecdotal reports which describe the effects of this compound within our experience index. Additional experience reports can be found here:

• Erowid Experience Vaults: 2-Oxo-PCE

The toxicity and long-term health effects of recreational O-PCE use do not seem to have been studied in any scientific context and the exact toxic dosage is unknown. This is because O-PCE has very little history of human usage. Anecdotal evidence from people who have tried O-PCE within the community suggests that there do not seem to be any negative health effects attributed to simply trying this substance at low to moderate doses by itself and using it sparingly (but nothing can be completely guaranteed).

O-PCE shares a close structural relationship to deschloroketamine (O-PCM) and ketamine (2-Cl-O-PCM), which has been speculated to have immuno-modulative properties.^[1] It is not known whether O-PCE also has these properties due to the lack of sufficient scientific research. However, the possibility should be kept in mind because prolonged use could potentially pose a serious threat to one's health and immune system.

It is strongly recommended that one use harm reduction practices, such as volumetric dosing, when using this substance to ensure the accurate administration of the intended dose.

Tolerance and addiction potential

As with other NMDA receptor antagonists, the chronic use of O-PCE can be considered moderately addictive with a high potential for abuse and is capable of causing psychological dependence among certain users. When addiction has developed, cravings and withdrawal effects may occur if a person suddenly stops their usage.

Tolerance to many of the effects of O-PCE develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). O-PCE presents cross-tolerance with all dissociatives, meaning that after the consumption of O-PCE all dissociatives will have a reduced effect.

Urinary tract effects

In terms of its long-term health effects when used repeatedly and excessively for extended periods of time, O-PCE seems to exhibit similar bladder and urinary tract problems to those found within ketamine, although to what extent is unclear. This is likely because O-PCE is significantly more potent than ketamine, meaning that less of the drug needs to be consumed. Symptoms of ketamine-induced cystitis can become extremely serious and can be described as:

• Urinary frequency - Urinary frequency is the need to empty the bladder every few minutes.
• Urinary urgency - This can be described as a sudden, compelling need to urinate.
• Urinary pressure - This is experienced as a constant sensation of fullness in the bladder that is unrelieved by urination.
• Pelvic and bladder pain - Pain can develop suddenly and severely, particularly as the bladder fills with urine.
• Hematuria - Hematuria is visible blood in the urine.
• Incontinence - This is the leakage of urine.

However, anecdotal evidence suggests that these symptoms can be largely avoided by refraining from using O-PCE on a regular basis (e.g. weekly at the bare minimum) and carefully monitoring and limiting one's intake of the substance.

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.

• Stimulants - Both stimulants and dissociatives carry the risk of adverse psychological reactions like anxiety, mania, delusions and psychosis and these risks are exacerbated when the two substances are combined.
• Depressants - Because both depress the respiratory system, this combination can result in an increased risk of suddenly falling unconscious, vomiting and choking to death from the resulting suffocation. If nausea or vomiting occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
• Alcohol - Even low doses of alcohol can cause severe interactions. Nausea, vomiting, amnesia, and other negative effects are extremely likely when mixed.

• Czech Republic: O-PCE is a Schedule I (List 4) substance. It may be used for research and restricted therapeutic purposes. ^[4]
• Germany: 2-Oxo-PCE is controlled under the NpSG (New Psychoactive Substances Act)^[5] as of July 18, 2019.^[6] 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.^[7]
• The Netherlands: O-PCE is currently not illegal in the Netherlands, and is sold as a research chemical.
• Switzerland: O-PCE is a controlled substance specifically named under Verzeichnis E.^[8]
• United Kingdom - 2-Oxo-PCE is a class B drug in the UK and is illegal to possess, produce, supply, or import. As an N-alkyl derivative of 2-Amino-2-phenylcyclohexanone, it is covered by the arylcyclohexylamine generic clause added to the Misuse of Drugs Act by S.I. 2013/239, which came into effect on the 26th February 2013.^[9]

• Responsible use
  • Volumetric dosing
• Research chemical
• Dissociative
• Methoxetamine
• 3-MeO-PCE
• O-PCM

• 2'-Oxo-PCE (Wikipedia)
• O-PCE (Isomer Design)
• 2-Oxo-PCE (Bluelight)
• Interview with a Ketamine Chemist (VICE)

• Morris, H., & Wallach, J. (2014). From PCP to MXE: A comprehensive review of the non-medical use of dissociative drugs. Drug Testing and Analysis, 6(7–8), 614–632. https://doi.org/10.1002/dta.1620