phencyclidine, ketamine, eticyclidine +4 morephencyclidine, ketamine, eticyclidine, tenocyclidine, 3-MeO-PCP, 3-MeO-PCE, deschloroketamine show less
Rolicyclidine
Rolicyclidine (1-phenylcyclohexylpyrrolidine) — PHP, PCPy — is a synthetic dissociative of the arylcyclohexylamine class. It sits between ketamine and PCP in potency.[1] It blocks glutamate signaling in the brain, producing a fragmented dissociative state where perception and conscious awareness come apart.
Rolicyclidine (1-phenylcyclohexylpyrrolidine) — PHP, PCPy — is a synthetic dissociative of the arylcyclohexylamine class. It occupies an intermediate position among PCP analogues — more potent than ketamine but less potent than PCP.[1] Rolicyclidine is an NMDA receptor antagonist, producing its effects by blocking ion flow through glutamate-gated channels in a use-dependent manner.
phencyclidine, ketamine, eticyclidine +4 morephencyclidine, ketamine, eticyclidine, tenocyclidine, 3-MeO-PCP, 3-MeO-PCE, deschloroketamine show less
Synthesized in 1958 by Parke-Davis chemists,[2] rolicyclidine was never developed for medical use. It appeared briefly on US street markets in the late 1970s as a PCP substitute,[3] generating a handful of clinical case reports before disappearing. It is now rarely encountered and internationally controlled under Schedule I.
Subjective effects include hallucinations, agitation, thought disorganization, motor impairment, and physical disconnection from the body.[4][5] The experience closely parallels PCP intoxication — perception fragments, thinking falls apart, and the body feels distant or uncontrollable. Paranoid thinking, involuntary movements, and episodes of acute psychosis are characteristic unwanted outcomes.
Physical dependence is inferred from PCP-class animal data,[6] and no lethal dose has been established. safety citation needed Rolicyclidine also permanently disables liver enzymes,[7] causing other drugs to accumulate to dangerous levels for days after use. The evidence base is extremely thin — almost everything known comes from a handful of case reports and animal studies, not controlled human research.
History[edit]
Discovery
Rolicyclidine was first synthesized in 1958 as part of Parke-Davis's arylcyclohexylamine research program.[2] The formal synthesis of this compound class was published in 1965 by Maddox, Godefroi, and Parcell.[8] Unlike PCP, which briefly entered surgical anesthesia before being withdrawn, rolicyclidine was never tested in clinical medicine.
Illicit market appearance
Rolicyclidine surfaced on US street markets in the late 1970s as a PCP substitute. Budd identified PHP as a new drug of abuse in 1980,[3] and Giannini subsequently documented its clinical effects — a single intoxication case treated with physostigmine,[4] then a series of 20 psychosis cases treated with haloperidol.[5] Those reports constitute the entire human clinical literature on rolicyclidine.
Scheduling and current status
Rolicyclidine was placed in Schedule I of the US Controlled Substances Act in the early-to-mid 1970s[2] — before its widespread street appearance. It is also listed under Schedule I of the 1971 United Nations Convention on Psychotropic Substances[9] and Class A in the United Kingdom.[10] It never achieved significant abuse prevalence and is now rarely encountered.[2]
The abbreviations PHP and PCPy are the primary identifiers in forensic and clinical literature — neither acquired lasting street names. Rolicyclidine circulated briefly during the peak of the US PCP epidemic, one of several ring-substituted analogues that appeared as PCP supplies fluctuated. Its transient market presence and pharmacological similarity to PCP left no distinct cultural identity.
Chemistry[edit]
Structural class
Rolicyclidine is an arylcyclohexylamine — the same chemical family as PCP and ketamine.[8] Its molecular formula is C₁₆H₂₃N (229.36 g/mol) and it exists as a single form with no mirror-image version.[2]
The nitrogen sits inside a five-membered pyrrolidine ring — one atom smaller than PCP's piperidine ring — a difference that shapes both potency and how quickly the body breaks it down.
Pharmacology[edit]
Mechanism of action
Rolicyclidine blocks the NMDA — the brain's main channel for glutamate-driven excitatory signaling — by plugging the channel pore after it opens.[11] The channel must first activate before the drug can enter, so neural activity itself determines where the drug acts.[11] This blockade prevents calcium from flowing through, disrupting normal communication between brain regions.
Metabolism
The body breaks down rolicyclidine primarily by opening its pyrrolidine ring, producing a metabolite called phenylcyclohexylamine (PCA). Among PCP-type compounds studied, rolicyclidine produces the largest proportion of this ring-opened product.[12]
Enzyme inhibition
Rolicyclidine permanently disables certain liver enzymes responsible for breaking down other drugs.[7] Because the inhibition is irreversible, the body must synthesize new enzyme to recover — a process taking approximately one to three days. Drug interaction risks therefore persist well after rolicyclidine's own effects have ended.
Neuroscience[edit]
Where it acts
No neuroimaging or brain studies have been conducted with rolicyclidine — neural effects are inferred from the broader NMDA antagonist class.[13] inferred Blocking NMDA receptors disrupts signaling between the cortex and thalamus, producing the characteristic dissociation — a functional split between sensory processing and conscious awareness. Dopamine reuptake inhibitor, shared across the PCP class,[14] activates reward pathways and contributes to euphoria.
Why it matters
NMDA blockade produces symptoms closely resembling schizophrenia: hallucinations, delusions, emotional withdrawal, flat affect, and cognitive impairment.[15] This connection — known as the glutamate hypothesis of psychosis — is why PCP analogues including rolicyclidine have served as pharmacological models of the illness. One clinical case showed that physostigmine reversed PHP psychosis,[4] suggesting the brain's acetylcholine system also plays a role.
Key unknowns include whether rolicyclidine produces neuroplastic changes like those documented for ketamine, whether the pyrrolidine ring alters NMDA receptor subtype selectivity relative to PCP, and whether its irreversible liver enzyme inhibition slows its own breakdown — potentially explaining prolonged effects at high doses.
Subjective Effects[edit]
Rolicyclidine produces a psychotomimetic dissociation — an experience where perception fragments, thinking collapses into incoherence, and the body feels remote or alien. It is not a controlled inner journey. Agitation and paranoia are not edge-case outcomes; they are characteristic features of the intoxication.[4][5]
Compared to ketamine, the experience runs longer and is more prone to overt psychotic features. Compared to PCP, the intensity ceiling is likely somewhat lower — rolicyclidine sits at an intermediate behavioral potency within the arylcyclohexylamine series[1] — though this comparison rests on animal data, not human trials.
Synthesized in 1958 by Parke-Davis chemists,[2] rolicyclidine was never developed for medical use and proceeded directly from synthesis to pharmacological obscurity. It appeared briefly on US illicit markets in the late 1970s as a PCP substitute,[3] generating a small cluster of clinical case reports before disappearing from circulation. It is now rarely encountered and remains internationally controlled under Schedule I.
Subjective effects include hallucinations, agitation, motor impairment, and thought disorganization.[4][5] The experience is reported as clinically indistinguishable from PCP intoxication — a psychotomimetic dissociation marked by perceptual distortion, confusion, and physical disconnection from the environment. Paranoid ideation, involuntary movement, and prolonged psychotic episodes are characteristic unsought effects.
Dependence liability is inferred from PCP-class primate studies demonstrating physical dependence;[6] no lethal dose has been established. safety citation needed Rolicyclidine uniquely inhibits liver enzymes irreversibly,[7] creating drug interaction risks that persist for days — a hazard not shared by most dissociatives, compounded by PCP-class risks of psychosis and cardiovascular stimulation.[8] No controlled human studies have been conducted; the entire evidence base consists of a handful of case reports from the early 1980s and animal behavioral data.
History[edit]
Discovery
Rolicyclidine was first synthesized in 1958 by chemists at Parke-Davis as part of the arylcyclohexylamine series.[2] The general synthesis of 1-arylcyclohexylamines — including rolicyclidine, PCP, and eticyclidine — was formally reported by Maddox, Godefroi, and Parcell in 1965.[9] Unlike PCP, which entered clinical anaesthesia before withdrawal due to emergence delirium, rolicyclidine was never developed for medical use.
Illicit market appearance
Rolicyclidine surfaced on US street markets in the late 1970s, sold as a PCP substitute. Budd published the first identification of PHP as a new drug of abuse in 1980,[3] and Giannini and colleagues subsequently documented its effects — a single intoxication case treated with physostigmine in 1982,[4] followed by a series of 20 PHP psychosis cases treated with haloperidol in 1985.[5] These publications constitute the entirety of the clinical literature on rolicyclidine in humans.
Scheduling and current status
Rolicyclidine was placed into Schedule I of the US Controlled Substances Act in the early-to-mid 1970s, prior to its widespread appearance on street markets.[2] It was subsequently listed under Schedule I of the 1971 United Nations Convention on Psychotropic Substances[10] and classified as Class A in the United Kingdom.[11] It never achieved significant abuse prevalence and is now rarely encountered.[2]
The abbreviations PHP (phenylcyclohexylpyrrolidine) and PCPy are the primary identifiers in forensic and clinical literature — neither acquired lasting street nomenclature. Rolicyclidine's brief window of illicit circulation coincided with the peak of the PCP epidemic in the United States, and it was one of several ring-substituted analogues (alongside eticyclidine and tenocyclidine) that appeared as PCP supplies fluctuated. Its lack of a distinct cultural identity reflects its transient market presence and pharmacological similarity to the parent compound.
Chemistry[edit]
Structural class
Rolicyclidine is an arylcyclohexylamine — the same structural family as PCP, eticyclidine, and ketamine. The core scaffold consists of a cyclohexane ring bearing both a phenyl group and an amine nitrogen at the 1-position. In rolicyclidine, the amine is incorporated into a five-membered pyrrolidine ring, distinguishing it from PCP's six-membered piperidine ring.[9]
This single-atom ring-size difference modulates both receptor binding potency and metabolic fate within the series. The pyrrolidine nitrogen is more exposed to oxidative metabolism, which accelerates ring-opening pathways and contributes to rolicyclidine's distinctive metabolic profile.
Molecular properties
| Molecular formula | C₁₆H₂₃N |
| Molecular weight | 229.36 g/mol |
The compound is achiral with no stereocenters,[2] so no consideration of active versus inactive enantiomers is required.
Physical properties
Physical property data derive from commercial chemical databases and have not been confirmed by peer-reviewed studies.[12]
| Melting point (free base) | 44–45 °C |
| Boiling point | 114–123 °C at 0.14 Torr |
| Water solubility | ~55 mg/L at 25 °C (computed) |
| pKa | ~9.86 |
With a pKa near 9.86, rolicyclidine is predominantly protonated at physiological pH, favoring water solubility in salt form and CNS penetration as the free base. The low melting point indicates a low-melting solid at room temperature. No data on salt forms, crystalline polymorphs, or degradation pathways have been published.
Pharmacology[edit]
Mechanism of action
Rolicyclidine blocks the NMDA — the brain's primary receptor for glutamate-driven excitatory signaling — by binding inside the open ion channel pore at the phencyclidine site.[13] This blockade is use-dependent: the channel must first be activated by glutamate before the drug can access its binding site, meaning neural activity itself gates the drug's effect.[13]
Once bound, rolicyclidine prevents calcium and other cations from flowing through the channel, disrupting normal excitatory transmission. The compound is also classified as a sigma receptor agonist and dopamine reuptake inhibitor based on the shared pharmacological profile of the arylcyclohexylamine class,[14] though no binding studies measuring rolicyclidine's specific affinity at these targets have been published. inferred
Metabolism
The pyrrolidine ring undergoes oxidation adjacent to the nitrogen atom, producing a ring-opened intermediate that ultimately generates phenylcyclohexylamine (PCA). Among PCP analogues studied, rolicyclidine produces the largest proportion of this metabolite.[15]
Data from the closely related compound 3-methoxyrolicyclidine identify multiple metabolic pathways: hydroxylation at various ring positions, aromatic hydroxylation, ring-opening followed by carboxylation, and glucuronidation of hydroxylated products.[16] For unsubstituted rolicyclidine, only hydroxylation and ring-opening pathways apply.
Enzyme inhibition
Rolicyclidine causes irreversible (mechanism-based) inhibition of cytochrome P450 liver enzymes.[7] In laboratory studies, preincubation with rolicyclidine reduced enzyme-dependent drug metabolism in a pattern consistent with permanent enzyme inactivation — the process was NADPH-dependent and followed pseudo-first-order kinetics.[7]
Because the inhibition is irreversible, the body must synthesize new enzyme to restore normal drug metabolism — a process taking approximately one to three days. Among PCP analogues, relative rates of enzyme inactivation rank PCP ≥ rolicyclidine > the seven-membered ring analogue.[7] This property creates drug interaction risks that outlast rolicyclidine's own pharmacological effects.
Neuroscience[edit]
Where it acts
No neuroimaging or electrophysiology studies have been conducted with rolicyclidine; neural mechanisms are inferred from the broader NMDA antagonist class. inferred
NMDA receptor blockade disrupts signaling between the cortex and thalamus, producing the characteristic dissociative state — a functional disconnection between sensory processing and higher-order awareness.[8] Dopamine reuptake inhibitor, documented for PCP-class compounds,[14] activates reward pathways and contributes to euphoria and reinforcing properties. The reversal of PHP psychosis by physostigmine in one case[4] suggests cholinergic neurotransmission may also play a role in the expression of PCP-class psychotomimesis.
Why it matters
The glutamate hypothesis of psychosis provides the primary framework for understanding PCP-class pharmacology. NMDA receptor blockade — whether drug-induced or occurring endogenously in disease — produces symptoms closely resembling schizophrenia: hallucinations, delusions, withdrawal, flat affect, and cognitive impairment.[17] PCP analogues including rolicyclidine have historically served as pharmacological models of schizophrenia, complementing the dopamine hypothesis.
A complementary account from predictive processing theory suggests NMDA antagonism disrupts the brain's ability to weigh sensory predictions, leading to the derealization, depersonalization, and ego dissolution characteristic of dissociative states.
Key unknowns include whether rolicyclidine produces neuroplastic changes comparable to those documented for ketamine, whether the pyrrolidine ring alters selectivity among NMDA receptor subtypes relative to PCP, and whether its irreversible liver enzyme inhibition causes auto-inhibition of its own metabolism — potentially explaining dose-dependent prolongation of effects.
Subjective Effects[edit]
Rolicyclidine's experiential character has not been studied under controlled conditions — what is known comes entirely from clinical case reports of illicit intoxication[4][5] and animal behavioral studies.[1] The reported experience closely parallels PCP intoxication: a psychotomimetic dissociation in which perception fragments, thinking becomes disorganized, and the body feels distant or uncontrollable. Set and setting are expected to modulate the experience significantly — calm environments may favor introspective dissociation, while stimulating or threatening contexts likely potentiate agitation and paranoia.
Compared to ketamine, rolicyclidine's effects are expected to be longer-lasting and more prone to psychotic features at equivalent dissociative depth. Compared to PCP, the overall intensity ceiling may be somewhat lower, consistent with rolicyclidine's intermediate behavioral potency in the arylcyclohexylamine series[1] — though this inference rests on animal data, not controlled human comparison.
Effect Grid
At common doses, a full dissociative experience emerges: pronounced depersonalization and derealization, distortion of body perception (body parts may feel enlarged, shrunken, or absent), and significant time distortion. Thought disorganization increases, with loose associations and impaired ability to maintain a coherent train of thought. Euphoria may be prominent. Auditory and visual distortions occur — sounds may seem distant or distorted, and visual field may appear flattened or tunnel-like.
Physically, marked ataxia and motor impairment are expected. Analgesia is substantial. Nystagmus, tachycardia, and mild hypertension are typical PCP-class effects at this range. Nausea and vomiting are possible.
Speech is significantly impaired. The individual is clearly intoxicated and should not attempt activities requiring coordination or judgment.
Modeled from the effect's dose-dependence curve — not per-substance measurements.
Visual acuity suppression · Perspective distortion · Depth perception distortion · Visual haze / noise · Sensory deprivation · Auditory distortion · Auditory suppression · Visual drifting · Auditory misinterpretation · Brightness alteration · Color alteration · Color suppression · Peripheral vision distortion · After-images · Tracers · Visual breathing · Visual morphing · Visual processing suppression · Internal hallucinations · External hallucinations · Auditory hallucinations · Perspective hallucinations · Environmental orbism / cubism · Visual scenery slicing · Visual flipping
Sensory deprivation · Auditory distortion · Auditory suppression · Visual drifting · Auditory misinterpretation · Brightness alteration · Color alteration · Color suppression · Peripheral vision distortion · After-images · Tracers · Visual breathing · Visual morphing · Visual processing suppression · Internal hallucinations · External hallucinations · Auditory hallucinations · Perspective hallucinations · Environmental orbism / cubism · Visual scenery slicing · Visual flipping
Body schema distortion · Bodily lightness · Body high · Restlessness · Nausea · Spontaneous body sensations · Involuntary body movements · Physical fatigue · Sedation · Stimulation · Tactile euphoria · Breathing alteration · Excessive sweating · Headache · Heart rate perception changes · Insomnia · Muscle relaxation · Muscle tension · Pupil dilation · Tingling / electric sensations · Vasoconstriction · Wakefulness · Bodily heaviness · Bodily pressures · Dry mouth · Laughter fits · Salivation · Trembling · Vomiting · Bodily dissociation · Tactile hallucination · Phantom limb sensations
Restlessness · Nausea · Spontaneous body sensations · Involuntary body movements · Physical fatigue · Sedation · Stimulation · Tactile euphoria · Breathing alteration · Excessive sweating · Headache · Heart rate perception changes · Insomnia · Muscle relaxation · Muscle tension · Pupil dilation · Tingling / electric sensations · Wakefulness · Bodily heaviness · Bodily pressures · Dry mouth · Laughter fits · Salivation · Trembling · Vomiting · Bodily dissociation · Tactile hallucination · Phantom limb sensations
Thought disorganization · Confusion · Focus suppression · Information processing suppression · Pattern recognition suppression · Language suppression · Memory fragmentation · Cognitive euphoria · Cognitive fatigue · Immersion enhancement · Introspection enhancement · Cognitive dysphoria · Creativity suppression · Motivation suppression · Suggestibility enhancement · Thought deceleration · Thought loops · Conceptual thinking · Thought acceleration · Thought connectivity · Delusions of sobriety · Creativity enhancement · Amnesia · Delusions · Delirium
Information processing suppression · Pattern recognition suppression · Language suppression · Memory fragmentation · Cognitive euphoria · Cognitive fatigue · Immersion enhancement · Introspection enhancement · Cognitive dysphoria · Creativity suppression · Motivation suppression · Thought deceleration · Thought loops · Conceptual thinking · Thought acceleration · Thought connectivity · Delusions of sobriety · Creativity enhancement · Amnesia · Delusions · Delirium
Euphoria · Dysphoria · Emotional suppression · Empathy suppression · Mania · Anxiety suppression · Anhedonia · Suicidal ideation
Empathy suppression · Anxiety suppression · Anhedonia · Suicidal ideation
Social disconnection · Ego inflation · Communication suppression · Sociability suppression · Craving · Cognitive disconnection · Identity alteration · Ego dissolution · Boundary dissolution
Craving · Cognitive disconnection · Identity alteration · Ego dissolution · Boundary dissolution
Timeline
First alerts appear as subtle shifts in bodily awareness — mild numbness, a sense of lightness, or faint perceptual detachment. The wide onset window (20–90 minutes) reflects variable absorption and the lipophilic nature of arylcyclohexylamines.
Dissociative effects build progressively: growing detachment from the body and environment, increasing numbness and analgesia, emerging motor impairment. Nausea is most likely during this phase.
Maximum dissociation: pronounced depersonalization, derealization, time distortion, and thought disorganization. Motor impairment and analgesia are at their strongest. The psychotomimetic effects documented in clinical case reports correspond to this phase.
Effects sustain at reduced intensity. Dissociation remains present but cognitive function begins to return incrementally. Motor impairment persists and coordination remains substantially degraded.
Gradual return toward baseline awareness. Residual numbness, mild confusion, and impaired coordination linger. Cognitive reconnection occurs unevenly — spatial awareness may return before full verbal fluency.
Residual effects may include subtle depersonalization, mood changes (elevation or dysphoria), fatigue, and impaired concentration lasting hours to a day after the primary experience resolves.
⚠ Do not drive or operate machinery for at least 24 hours after ingestion — residual dissociative impairment and slowed reaction time may persist well beyond subjective resolution of effects.
Safety[edit]
- Acute toxicity
- Low
- Chronic toxicity
- Low
- Withdrawal
- Moderate
- Tolerance buildup
- moderate
- Tolerance reset
- 10 days
- Physical
- Moderate
- Psychological
- Moderate
- Compulsive redosing
- Moderate
- Dose escalation
- Moderate
- Cross-tol.
- phencyclidine · ketamine · eticyclidine
Toxicity
Acute toxicity
No lethal dose data have been published for rolicyclidine. safety citation needed Acute risks are inferred from PCP-class pharmacology: dangerous rises in blood pressure and heart rate, respiratory depression at high doses, overheating, and muscle breakdown.[13] inferred A series of 20 clinical intoxications reported no fatalities,[5] and physostigmine reversed symptoms in one case.[4]
Liver enzyme inhibition
Rolicyclidine permanently disables liver enzymes that break down other drugs.[7] Drugs with narrow safety margins — certain opioids, heart medications, blood thinners — can accumulate to dangerous levels as a result. Recovery takes approximately one to three days, so this risk persists long after rolicyclidine's own effects are gone.
Psychological risks
PCP-class dissociatives can trigger acute psychosis: hallucinations, paranoid thinking, agitation, and disorganized behavior.[5][15] PHP-induced psychosis is clinically indistinguishable from PCP psychosis.[5]
Prolonged psychotic episodes extending beyond the acute drug period are documented for the PCP class. inferred Violence and self-injury during intoxication are recognized risks — the combination of psychosis, lost motor control, and inability to feel pain removes normal protective reflexes.[13]
Tolerance and dependence
No tolerance or dependence data specific to rolicyclidine exist. safety citation needed PCP-class drugs produce physical dependence in animal studies: oral PCP self-administration in rhesus monkeys produces measurable withdrawal,[6] and PCP withdrawal disrupts behavior beyond psychological craving.[16] PCP functions as a reinforcer in self-administration studies,[17] and cross-tolerance across the class is supported by drug discrimination data.[1]
Drug Interactions
No interaction studies specific to rolicyclidine have been published. All risks are inferred from mechanism and class pharmacology. inferred
Liver enzyme interactions
Rolicyclidine's irreversible enzyme inhibition[7] is the most distinctive interaction risk in the PCP structural analog series. Drugs with narrow safety margins — certain opioids (codeine, tramadol, fentanyl), heart rhythm medications, and blood thinners — can accumulate to dangerous levels when combined. The interaction window persists for days after rolicyclidine's effects have worn off.
CNS depressant combinations
Additive sedation and respiratory depression is expected with alcohol, GHB/GBL, opioids, and benzodiazepines. safety citation needed
Stimulant and serotonergic combinations
Combined cardiovascular stimulation with cocaine or MDMA is plausible via additive effects on dopamine and the sympathetic nervous system. inferred Tramadol co-administration carries theoretical risk of dangerous serotonin overload — a potentially life-threatening overheating and seizure response — compounded by rolicyclidine's enzyme inhibition potentially raising tramadol's active metabolite levels.
Contraindications
7 knownNo published contraindications specific to rolicyclidine exist. Class-level contraindications include: inferred
- Psychotic disorders — PCP-class drugs trigger and worsen psychosis; personal or family history of psychotic illness is an absolute contraindication
- Heart conditions — dangerous blood pressure and heart rate increases documented for the PCP class
- Breathing difficulties — respiratory depression at high doses
- Concurrent sedatives — additive respiratory and cardiovascular depression
- Liver impairment — rolicyclidine's irreversible enzyme inhibition may compound existing liver dysfunction, increasing risk from both rolicyclidine and other medications
Harm Reduction[edit]
Forms & Identification
Rolicyclidine is exceptionally rare on modern drug markets. Any substance sold as PHP or PCPy should be treated with extreme skepticism — substitution and mislabeling are likely given the compound's obscurity. Standard reagent testing cannot reliably distinguish rolicyclidine from other arylcyclohexylamines. Laboratory analysis through a drug checking service is the only reliable identification method.
Guidelines
- Test all material through a drug checking service — reagent kits alone cannot confirm identity for rare arylcyclohexylamines
- Start with the lowest possible amount and wait for full onset before considering redosing
- Have a sober, trusted sitter present throughout
- Choose a quiet, familiar environment with no access to heights, water, or traffic
- Remove sharp objects and potential hazards from the immediate area
- Do not combine with any other substance — rolicyclidine's irreversible liver enzyme inhibition makes interaction timing unpredictable
- Do not drive or operate machinery for at least 24 hours after use
- Enzyme inhibition effects may persist for days, affecting how the body processes other drugs and medications during that window
Set & Setting
PCP-class dissociatives are highly sensitive to environment. Calm, familiar settings with trusted companions reduce the risk of agitation escalating into crisis. Stimulating, crowded, or unfamiliar environments increase the probability of paranoid reactions.
A sober sitter is essential — PCP-class intoxication can produce sudden behavioral changes that the affected person cannot self-manage.
Aftercare & integration. PCP-class dissociative experiences — particularly those involving psychotic features — can leave lasting psychological residue. Allow at least 48–72 hours of reduced activity and adequate sleep before returning to normal responsibilities.
Confusion, emotional suppression, or fragmented memory are common in the days following use. Talking through the experience with a trusted person can help restore coherence.
If psychotic symptoms — paranoia, hallucinations, thought disorganization — persist beyond 48 hours, seek professional evaluation. PCP-class compounds can trigger prolonged psychotic episodes that require clinical intervention.
Rolicyclidine's liver enzyme inhibition may affect how the body handles medications and other substances for several days. Consult a healthcare provider before resuming regular medications.
Recovery & Support
Regular use of PCP-class dissociatives can produce psychological dependence and gradual cognitive impairment. If use has become compulsive or is interfering with daily functioning, professional support is available.
Addiction helplines, harm reduction organizations, and substance use counselors familiar with dissociative drugs can provide appropriate guidance. Recovery from dissociative dependence typically benefits from both psychological support and sustained abstinence — cognitive effects improve with time.
Recovery resources, crisis lines, and support pathways → View all
Emergency Response
Recognizing an emergency: Severe agitation or aggression that cannot be verbally de-escalated. Seizures. Loss of consciousness. Chest pain or difficulty breathing. Body temperature hot to the touch. Self-harming behavior or complete disconnection from reality.
Immediate steps:
- 1. Call emergency services immediately if any of the above signs are present
- 2. Do not physically restrain the person unless they are in immediate danger of harming themselves or others — restraint can escalate agitation
- 3. Move the person to a quiet, low-stimulation environment if safely possible
- 4. If unconscious, place in the recovery position and monitor breathing
- 5. Do not induce vomiting
What to tell the dispatcher: Name the substance (rolicyclidine / PHP / PCP structural analog), estimated amount and time of ingestion, and current symptoms. Good Samaritan laws in many jurisdictions protect people who call for help during drug emergencies.
Legal Status[edit]
Rolicyclidine is internationally controlled as a phencyclidine-type substance[9] and has never been approved for medical use in any jurisdiction.
| Jurisdiction | Classification | Key provisions |
|---|---|---|
| United States | Schedule I (CSA; DEA #7458) | Controlled since the 1970s; never approved for medical use[2] |
| United Kingdom | Class A (Misuse of Drugs Act 1971) | Added under the 1984 Modification Order[10] |
| International | Schedule I (1971 UN Convention) | Listed as phencyclidine-type substance[9] |
| Australia | Not individually confirmed | Likely controlled under domestic analogue provisions per UN Convention obligationscitation needed |
| Canada | Not individually confirmed | Likely controlled under CDSA per UN Convention obligationscitation needed |
Analogue act considerations
In jurisdictions with structural analog laws — such as the US Federal Analogue Act — any novel arylcyclohexylamine derivative intended for human consumption may be treated as a controlled substance by analogy to PCP and rolicyclidine, regardless of whether the specific derivative is individually scheduled.
Legal status changes frequently and varies by jurisdiction. This information is not legal advice.
Safety[edit]
- Acute toxicity
- Low
- Chronic toxicity
- Low
- Withdrawal
- Moderate
- Tolerance buildup
- moderate
- Tolerance reset
- 10 days
- Physical
- Moderate
- Psychological
- Moderate
- Compulsive redosing
- Moderate
- Dose escalation
- Moderate
- Cross-tol.
- phencyclidine · ketamine · eticyclidine
Toxicity
Acute toxicity
No lethal dose data have been published for rolicyclidine. safety citation needed Acute toxicity is inferred from PCP class pharmacology: dangerous rises in blood pressure and heart rate, respiratory depression at high doses, overheating, and muscle breakdown are documented for PCP and plausibly apply to rolicyclidine.[8] inferred
The published case series of 20 PHP intoxications reported no fatalities.[5] In a single case, physostigmine produced rapid symptom reversal.[4]
Liver enzyme inhibition
Rolicyclidine irreversibly disables certain liver enzymes responsible for metabolizing other drugs.[7] Co-administered substances — particularly those with narrow safety margins — may accumulate to dangerous levels. Because the body must build new enzyme to recover (approximately one to three days), this interaction risk persists well beyond rolicyclidine's own duration of action.
Psychological risks
PCP-class dissociatives are established triggers for acute psychosis: hallucinations, paranoid thinking, agitation, and disorganized behavior.[5][17] PHP-induced psychosis is clinically indistinguishable from PCP psychosis.[5]
Prolonged psychotic episodes extending beyond the acute drug period are documented for the PCP class, particularly with high doses or repeated use. inferred Violence and self-injury during PCP-class intoxication are recognized risks, driven by the combination of psychosis, loss of motor control, and inability to feel pain.[8]
Tolerance and dependence
No tolerance or dependence data specific to rolicyclidine have been published. safety citation needed
PCP-class drugs produce physical dependence in primate models. Oral PCP self-administration in rhesus monkeys causes physical dependence with measurable withdrawal, and males show greater withdrawal severity than females.[6] PCP withdrawal disrupts normal behavior beyond psychological craving.[18] High-affinity NMDA antagonists including PCP function as reinforcers in self-administration studies.[19]
Cross-tolerance among PCP-class dissociatives is supported by full generalization in drug discrimination tests[1] — consistent with shared NMDA channel blockade as the common mechanism.
Drug Interactions
No interaction studies specific to rolicyclidine have been published. All risks are inferred from mechanism and class pharmacology. inferred
Liver enzyme interactions
Rolicyclidine's irreversible enzyme inhibition[7] creates the most distinctive interaction risk among PCP analogues. Drugs with narrow safety margins — including certain opioids (codeine, tramadol, fentanyl), heart rhythm medications, and blood thinners — may reach dangerous levels when co-administered. Because the inhibition is irreversible, the interaction window persists for days beyond rolicyclidine's own effects.
CNS depressant combinations
Additive sedation and respiratory depression is expected with alcohol, GHB/GBL, opioids, and benzodiazepines. safety citation needed
Stimulant and serotonergic combinations
Combined cardiovascular stimulation with cocaine or MDMA is plausible via additive effects on dopamine and the sympathetic nervous system. Tramadol co-administration carries theoretical serotonin syndrome risk, compounded by rolicyclidine's enzyme inhibition potentially elevating tramadol's active metabolite levels. inferred
Contraindications
7 knownNo published contraindications specific to rolicyclidine exist. Class-level contraindications include: inferred
- Psychotic disorders — PCP-class drugs trigger and worsen psychosis; personal or family history of psychotic illness is an absolute contraindication
- Heart conditions — dangerous blood pressure and heart rate increases documented for the PCP class
- Breathing difficulties — respiratory depression at high doses
- Concurrent sedatives — additive respiratory and cardiovascular depression
- Liver impairment — rolicyclidine's irreversible enzyme inhibition may compound existing liver dysfunction, increasing risk from both rolicyclidine and other medications
Harm Reduction[edit]
Forms & Identification
Rolicyclidine is exceptionally rare on modern drug markets. Any substance sold as PHP or PCPy should be treated with extreme skepticism regarding identity and purity — the probability of substitution or mislabeling is high given the compound's obscurity. Standard reagent testing may not reliably distinguish rolicyclidine from other arylcyclohexylamines; laboratory analysis through a drug checking service is the only reliable identification method.
Guidelines
- Test all material through a drug checking service — reagent kits alone cannot confirm identity for rare arylcyclohexylamines
- Start with the lowest possible amount and wait for full onset before considering redosing
- Have a sober, trusted sitter present throughout
- Choose a quiet, familiar environment with no access to heights, water, or traffic
- Remove sharp objects and potential hazards from the immediate area
- Do not combine with any other substance — rolicyclidine's irreversible liver enzyme inhibition makes interaction timing unpredictable
- Do not drive or operate machinery for at least 24 hours after use
- Keep in mind that enzyme inhibition effects may persist for days, affecting how your body processes other drugs and medications during that window
Set & Setting
PCP-class dissociatives are highly sensitive to environment. Calm, familiar settings with trusted companions reduce the risk of agitation-escalating-to-crisis cycles. Stimulating, crowded, or unfamiliar environments increase the probability of paranoid reactions. A sober sitter is essential — PCP-class intoxication can produce sudden behavioral changes that the user cannot self-manage.
Aftercare & integration. PCP-class dissociative experiences — particularly those involving psychotic features — can leave lasting psychological residue. Allow at least 48–72 hours of reduced activity and adequate sleep before returning to normal responsibilities.
Confusion, emotional suppression, or fragmented memory of the experience are common in the days following use. Talking through the experience with a trusted person can help restore coherence. If psychotic symptoms (paranoia, hallucinations, thought disorganization) persist beyond 48 hours, seek professional evaluation — PCP-class compounds can trigger prolonged psychotic episodes that require clinical intervention.
Be aware that rolicyclidine's liver enzyme inhibition may affect how your body handles medications and other substances for several days after use. Consult a healthcare provider before resuming any regular medications.
Recovery & Support
Regular use of PCP-class dissociatives can produce psychological dependence and cognitive impairment that develops gradually. If use has become compulsive or is interfering with daily functioning, professional support is available.
Addiction helplines, harm reduction organizations, and substance use counselors familiar with dissociative drugs can provide appropriate guidance. Recovery from dissociative dependence often benefits from both psychological support and sustained abstinence — cognitive effects typically improve with time.
Recovery resources, crisis lines, and support pathways → View all
Emergency Response
Recognizing an emergency: Severe agitation or aggression that cannot be verbally de-escalated. Seizures. Loss of consciousness. Chest pain or difficulty breathing. Body temperature hot to the touch. Self-harming behavior or complete disconnection from reality.
Immediate steps:
- 1. Call emergency services immediately if any of the above signs are present
- 2. Do not physically restrain the person unless they are in immediate danger of harming themselves or others — restraint can escalate agitation
- 3. Move the person to a quiet, low-stimulation environment if safely possible
- 4. If unconscious, place in the recovery position and monitor breathing
- 5. Do not induce vomiting
What to tell the dispatcher: Name the substance (rolicyclidine / PHP / PCP structural analog), estimated amount and time of ingestion, and current symptoms. Good Samaritan laws in many jurisdictions protect people who call for help during drug emergencies.
Legal Status[edit]
Rolicyclidine is internationally controlled as a phencyclidine-type substance. It is listed under Schedule I of the 1971 United Nations Convention on Psychotropic Substances,[10] alongside eticyclidine and tenocyclidine. It has never been approved for medical use in any jurisdiction.
| Jurisdiction | Classification | Key provisions |
|---|---|---|
| United States | Schedule I (CSA; DEA #7458) | Controlled since the 1970s; never approved for medical use[2] |
| United Kingdom | Class A (Misuse of Drugs Act 1971) | Added under the 1984 Modification Order[11] |
| International | Schedule I (1971 UN Convention) | Listed as phencyclidine-type substance[10] |
| Australia | Not individually confirmed | Likely controlled under domestic analogue provisions per UN Convention obligationscitation needed |
| Canada | Not individually confirmed | Likely controlled under CDSA per UN Convention obligationscitation needed |
Analogue act considerations
In jurisdictions with structural analog provisions (e.g., the US Federal Analogue Act), any novel arylcyclohexylamine derivative intended for human consumption may be treated as a controlled substance by analogy to PCP and rolicyclidine, regardless of whether the specific derivative is individually scheduled.
Frequently asked questions
What is Rolicyclidine?
Rolicyclidine is a dissociative anaesthetic of the arylcyclohexylamine class, synthesized by Parke-Davis in 1958 and never developed for medical use. It acts as a non-competitive NMDA receptor antagonist at the phencyclidine binding site, with intermediate potency among PCP analogues.
How long does Rolicyclidine last?
Total duration by route of administration — Oral: 6 – 12 hours; Smoked: 4 – 6 hours; Insufflated: 4 – 6 hours. Ranges vary with dose and individual factors; see the duration table for onset, peak, and after-effect phases.
Where can I find dosage information for Rolicyclidine?
Psychedex publishes a dosage table for Rolicyclidine on this page covering these routes of administration: smoked, insufflated, oral. Dose values are presented only in that table, always alongside their route of administration.
What are dangerous combinations with Rolicyclidine?
The highest-severity documented interactions for Rolicyclidine: GHB, GBL (Lethal), Ibogaine (Lethal), Amphetamines (Dangerous), Anticholinergics (Dangerous), Antihistamines (Dangerous). See the interactions section for the full list with mechanisms and severity levels.
Is Rolicyclidine addictive?
Psychedex records tolerance and dependence data rather than a yes/no rating. Recorded tolerance indicators for Rolicyclidine: tolerance builds moderate; full reset takes 10 days; cross-tolerance develops with phencyclidine, ketamine, eticyclidine, tenocyclidine, 3-MeO-PCP, 3-MeO-PCE, deschloroketamine. See the article's dependence and safety sections for recorded dependence data.
experience reports
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First-person accounts of subjective effects, timing, and outcomes — submitted for harm reduction.
references
- [1] ^abcBrady KT, Balster RL (1981) Discriminative stimulus properties of phencyclidine and five analogues in the squirrel monkey. — Pharmacology, Biochemistry, and Behavior PMID:7208560
- [2]
- [3]
- [4]
- [5]
- [6] ^abPerry JL, Normile LM, Morgan AD, Carroll ME (2006) Sex differences in physical dependence on orally self-administered phencyclidine (PCP) in rhesus monkeys — Experimental and Clinical Psychopharmacology PMID:16503706
references
- [1] ^abcdBrady KT, Balster RL (1981) Discriminative stimulus properties of phencyclidine and five analogues in the squirrel monkey. — Pharmacology, Biochemistry, and Behavior PMID:7208560
- [2]
- [3]
- [4]
- [5]
- [6] ^abPerry JL, Normile LM, Morgan AD, Carroll ME (2006) Sex differences in physical dependence on orally self-administered phencyclidine (PCP) in rhesus monkeys — Experimental and Clinical Psychopharmacology PMID:16503706