Disregard Everything I Say

Dosage (oral)
Threshold : 50 mg
Light : 70 – 85 mg
Common : 85 – 110 mg
Strong : 110 – 150 mg
Heavy : >150 mg

Duration (oral)
Total duration : 2 - 5 hours
Onset  : 15 - 30 minutes
After effects : 4 - 24 hours

Diphenidine (1-(1,2-diphenylethyl)piperidine) is a dissociative NMDA receptor antagonist and anesthetic drug that has been sold online as a research chemical.

The synthesis of diphenidine was first reported in 1924 and employed a nitrile displacement reaction analogous to the one that would later be used to discover phencyclidine in 1956. Shortly after the 2013 UK ban on arylcyclohexylamines, diphenidine and the related compound methoxphenidine became available on the grey market. Anecdotal reports describe high doses of diphenidine producing “bizarre somatosensory phenomena and transient anterograde amnesia.”

In 2014, there have been two published reports of diphenidine being sold in combination with synthetic cannabinoids in Japanese herbal incense blends. A herbal incense sold in the Shizuoka Prefecture under the name “Aladdin (sic) Spacial Edition” was found to contain diphenidine and 5-fluoro-AB-PINACA at concentrations of 289 mg/g and 55.5 mg/g, respectively. Another product called ‘‘Herbal Incense. The Super Lemon’’ containing AB-CHMINACA, 5F-AMB, and diphenidine was implicated in a fatal overdose.

Based on collaborative anecdotal evidence, diphenidine seems to have a much more rapid onset and lower half life when vaporized or smoked. When consumed this way, it is a suspected to be carcinogenic when excess heat is used. Some user reports have concluded that vaporization requires as low as 20% of what would be a common oral dose for that person.

In terms of its chemistry, diphenidine is a diarylethylamine related to methoxphenidine. It is named for its two phenyl and piperidine groups. Diphenidine’s crystalline structure is very similar to MK-801 (Dizocilpine) and shares many of the same effects. These two compounds are homeomorphs. Diphenidine is synthesized in a reaction analogous to the synthesis of PCP. The (R)-enantiomer of diphenidine has a remarkable high affinity as a NMDA receptor channel blocker.

In terms of its pharmacology, diphenenidine acts as an NMDA receptor antagonist. NMDA receptors allow for electrical signals to pass between neurons in the brain and spinal column; for the signals to pass, the receptor must be open. NMDA receptor antagonists close the NMDA receptors by blocking them. This disconnection of neurons leads to loss of feeling, difficulty moving, and eventually the famous “hole”.

Although vendors of diphenidine have stated the compound acts as a dopamine-reuptake inhibitor and a serotonin reuptake inhibitor with µ-opioid affinity and typical dissociative effects, to date diphenidine has not been screened for affinity at the dopamine transporter. If this is indeed the case, however, it provides an explanation for its euphoric and often stimulating effects.

Diphenidine and related diarylethylamines have been studied in vitro as treatments for neurotoxic injury. Diphenidine may be a stronger NMDA receptor antagonist for neurogenis and neurological repair than other more common NMDA receptor antagonistic dissociatives such as ketamine, dextromethorphan, PCP analogs, Iboga and methoxetamine.

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWiki contributors. The listed effects will rarely if ever occur all at once but heavier dosages will increase the chances and are more likely to induce a full range of effects.

Physical effects:

The subjective physical effects of diphenidine can be broken down into nine components all of which progressively intensify proportional to dosage. These are described below and generally include:

• Tactile disconnection
• Spontaneous tactile sensations - The diphenidine body high is a sharp, pleasurable tingling sensation which is location specific to the hands, feet and head.
• Tactile suppression - This partially to entirely suppresses one’s own sense of touch, creating feelings of numbness within the extremities. It is responsible for the anaesthetic properties of this substance.
• Physical autonomy
• Motor control loss - A loss of gross and fine motor control alongside of balance and coordination is prevalent within diphenidine and becomes especially strong at higher dosages. This means that one should be sitting down before the onset (unless one is experienced) in case of falling over and injuring oneself.
• Euphoria - This results in feelings of physical euphoria which range between mild pleasure to powerful all-encompassing bliss.
• Decreased bodily weight - This creates the sensation that the body is floating and has become entirely weightless. This effect is strangely stimulating and encourages physical activities at low to moderate dosages by making the body feel light and effortless to move.
• Dizziness - Although uncommon, some people report dizziness under the influence of diphenidine.
• Nausea - It’s worth noting that high dose diphenidine trips can sometimes result in nausea and vomiting at the peak of the trip. For most people, this is surprisingly not as unpleasant as they would initially expect due to the accompanying detachment from the physical senses.

Cognitive effects:

The general head space of diphenidine is often described as particularly euphoric and clear headed in comparison to that of DXM and Ketamine. The specific cognitive effects can be broken down into 8 separate subcomponents which are listed and described below:

• Consciousness disconnection
• Ego suppression, loss and death
• Thought deceleration
• Information processing suppression
• Time distortion
• Euphoria
• Introspection
• Deja-Vu
• Conceptual thinking
• Compulsive redosing

Visual effects:

Suppression:

This substance does not enhance visual stimuli; instead it tends to degrade and decrease visual aptitude in a variety of ways which generally includes:

• Visual disconnection - This eventually results in the diphenidine’s equivalent of the famous “K-hole” or more specifically, holes, space and voids alongside of structures.
• Visual acuity suppression
• Double vision - This component is prevalent at moderate to heavy dosages and makes reading impossible unless one closes an eye.
• Pattern recognition suppression - This effect generally occurs at higher dosages and makes one unable to recognize and interpret perceivable visual data.

Distortions:

Diphenidine exhibits a full array of dissociative distortions and alterations in visual perception which generally includes:

• Perspective distortions
• Environmental cubism
• Environmental orbism
• Scenery slicing

Geometry:

The visual geometry found within diphenidine can be described as very dark and bland when compared to that of Ketamine or DXM and often consists of many tiny interlocking and woven lines. It does not extend beyond level 4 and can be comprehensively described through its variations as simplistic in complexity, algorithmic in style, synthetic in feel, unstructured in organization, dimly lit in lighting, multicoloured in scheme, glossy in shading, soft in edges, small in size, slow in speed, smooth in motion, equal in rounded and angular corners, immersive in depth and consistent in intensity.

Hallucinatory states:

At high dosages, diphenidine can produce a full range of high level hallucinatory states in a fashion that that is less consistent and reproducible than that of many other commonly used psychedelics. These effects include:

• Internal hallucinations (Autonomous entities, Settings, sceneries, and landscapes, Alterations in perspective and Scenarios and plots) - In comparison to other dissociatives, this effect can occur at heavy dosages but is considerably less common than the same effect found within psychedelics and deliriants. It can be comprehensively described through its variations as delirious in believability, fixed in style, equal in new experiences and memory replays in content, autonomous in controllability and solid in style.

Auditory effects:

The auditory effects are common in their occurrence and exhibit a range of effects which commonly includes:

• Enhancements
• Suppression
• Distortions
• Hallucinations

Physical health effects, potential addiction and tolerance:

The toxicity and long term health effects of recreational diphenidine use does not seem to have been studied in any scientific context and the exact toxic dosage is unknown. This is because diphenidine is a research chemical with very little history of human usage. Anecdotal evidence from people who have tried diphenidine within the psychonaut community suggests that there are no negative health effects attributed to simply trying this drug at low to moderate doses or using it very sparingly (but nothing can be completely guaranteed).

There is a very strong tolerance build up with diphenidine which results in the need to consume increasingly large doses in order to achieve the same level of effects. This should reset to baseline after 1 - 2 weeks. There may well be some addictive potential but this is still unknown.

Tolerance may be mitigated via preparing the citrate salt by mixing the chemical with citric acid or lemon juice, which will aid in absorption and increase effects.

Legal issues:

Diphenidine is currently a legal grey area drug worldwide and is freely available through the use of online research chemical vendors. However, this does not guarantee anyone to be immune from legal prosecution should they be found in possession of this substance as the legality is likely to vary from country to country.

Conclusion:

In conclusion, diphenidine feels almost identical to MXE with only subtle differences. It is a powerful hallucinogen and just as capable of inducing deep states of detachment which rival that of the other more commonly used dissociatives.

This substance breakdown was written through collaboration between PsychonautWiki contributors Kaylee, PJosepherum, Josikins and Oscarette. The full article, including references, is available here.