MXiPr

Methoxisopropamine (MXiPr) is a synthetic dissociative in the arylcyclohexylamine family. It is an analogue of methoxetamine (MXE), with an isopropyl group attached to the nitrogen instead of MXE’s ethyl group. MXiPr appeared on the research-chemical market around 2020. Laboratory work has confirmed NMDA receptor activity, but its effects and toxicity in humans remain poorly understood.

Chemistry and history

MXiPr is 2-(isopropylamino)-2-(3-methoxyphenyl)cyclohexan-1-one. It shares the methoxyphenylcyclohexanone core of MXE and differs mainly in the larger isopropyl substituent on the nitrogen. It is closely related to MXPr, which has a straight-chain propyl group instead.

The compound was identified in illegal products in Japan alongside MXPr and DMXE in a 2022 study. The paper documented the appearance of these MXE-related derivatives in products circulating on the illicit market (Tanaka and colleagues, 2022).

Pharmacology

MXiPr has been shown to block NMDA receptors in laboratory experiments. Patch-clamp recordings using mouse neurons gave an IC₅₀ of 0.661 μM, close to the values measured for MXE and DMXE in the same study. This provides direct evidence of NMDA receptor antagonism, although it does not establish a human potency estimate (Irie and colleagues, 2022).

Its broader receptor profile has not been mapped. In particular, claims that it strongly inhibits serotonin reuptake are based mainly on structural comparison with MXE rather than a comprehensive set of transporter assays.

Subjective effects

The PsychonautWiki profile of MXiPr draws on early anecdotal reports and is marked as incomplete. Users describe noticeable stimulation alongside dissociation, but also emphasise how unpredictable the experience can be.

Physical effects

Reports describe stimulation at lower intensities and a shift towards sedation as dissociation becomes stronger. A sharp tingling sensation, bodily lightness and a feeling of weightlessness are also mentioned. Motor coordination and balance may deteriorate, while tactile suppression can produce numbness and reduced awareness of the body.

Other reported effects include pain relief, dizziness, nausea, increased perspiration, increased heart rate and blood pressure, and abnormal heartbeat. Seizures have been mentioned in anecdotal reports, but their frequency and relationship to exposure are not established.

Cognitive effects

Users report euphoria, disinhibition, conceptual thinking, creativity and changes in time perception. Depersonalisation, derealisation and memory suppression may accompany stronger dissociation. Mania and delusional thinking are also described, although the available reports are too limited to determine how common they are.

Auditory and dissociative effects

Auditory distortions may be pronounced in some accounts, with sounds described as muffled, delayed or fragmented. Tactile, visual and consciousness disconnection can develop into a more complete dissociative state. Some reports describe a dream-like afterglow, while others mention prolonged physical discomfort or memory gaps.

Toxicity and research limitations

There are no controlled human studies establishing the acute or long-term toxicity of MXiPr. The receptor study confirms NMDA antagonism, but does not provide a clinical safety profile. The available user reports mention seizures, amnesia and prolonged physical discomfort, but do not show how often they occur.

Its similarity to MXE does not mean that MXiPr has the same potency or adverse-effect profile. The compound’s metabolism, interaction profile and dependence potential remain uncertain.

Related compounds

MXiPr is related to Methoxetamine, MXPr and DMXE. It differs from MXPr in the shape of the nitrogen substituent and from DMXE in the aromatic-ring substituent.