2C-P (2,5-dimethoxy-4-propylphenethylamine) is an extremely potent, long-duration psychedelic phenethylamine of the 2C family, first synthesized by Alexander Shulgin and documented in PiHKAL (1991). It is widely regarded as one of the most dangerous members of the 2C family, not due to any specific organ toxicity, but because its extreme potency by weight, slow onset, and very long duration create conditions that reliably produce dosing errors with serious consequences. Shulgin himself rated it one of the most powerful compounds in his PiHKAL catalog.
At common doses (5–12 mg), 2C-P produces a psychedelic experience lasting 12–20 hours — significantly longer than any other common 2C compound. The onset is slow (1.5–3 hours), which has led to many documented cases of users redosing because they believed the initial dose was insufficient, only to have both doses activate simultaneously, producing overwhelming, medically concerning experiences. At higher doses, 2C-P is capable of producing profound perceptual distortion, ego dissolution, and physiological stimulation comparable to a massive dose of any classical psychedelic.
The harm reduction community treats 2C-P with considerable respect. The combination of extreme potency (active at 5 mg or below in sensitive individuals), slow onset, extremely long duration, and steep dose-response curve makes it uniquely dangerous compared to other 2C compounds. Multiple serious adverse events and at least one confirmed fatality have been associated with 2C-P use in the literature. It is not a compound recommended for inexperienced users under any circumstances, and even experienced users benefit from the most stringent harm reduction practices.
Safety at a Glance
High Risk- Strong Warning: Not Recommended for Most Users
- Dosing — Start Extremely Low
- Toxicity: Extreme Caution Required 2C-P is one of the most hazardous common research chemical psychedelics from a practical sta...
- Overdose risk: Overdose The LD50 of 2C-P has not been established. However, it is believed that 2C-P is likely t...
If someone is in crisis, call 911 or Poison Control: 1-800-222-1222
Dosage
oral
Duration
oral
Total: 10 hrs – 20 hrsHow It Feels
The onset is agonizingly slow. Two hours may pass -- sometimes three -- with nothing but a growing, gnawing nausea and a sense that something very large is gathering force in the distance. The come-up of 2C-P is a test of patience and nerve, because the temptation to supplement the dose during this extended waiting period is precisely the mistake that transforms a powerful experience into an overwhelming one. When the effects finally begin to declare themselves, they do so with an authority that makes the wait comprehensible in retrospect.
By the three to four hour mark, 2C-P has fully revealed its character as one of the most powerful psychedelics in the 2C family. Visual effects are extraordinary in both intensity and detail. Geometric patterns of staggering complexity cascade across every surface -- dense, multilayered, and rendered in vivid, saturated color. The patterns have an architectural quality, as though the visual cortex is constructing elaborate three-dimensional structures and projecting them onto the flat surfaces of ordinary reality. Closed-eye visuals are immersive and can approach the vividness of DMT-like spaces. Objects in the environment may transform dramatically, and faces can become intensely distorted or take on animal-like qualities. The visual component alone would place 2C-P among the most potent visual psychedelics available.
The headspace is deep and demanding. Thought processes are profoundly altered, with the usual boundaries between concepts becoming fluid and permeable. Introspection is powerful and can access emotional territory that feels genuinely significant. Ego dissolution is possible at higher doses. The body load is substantial: nausea that can persist for hours, muscle tension, vasoconstriction, and a relentless stimulant energy that keeps the mind churning even when exhaustion sets in. The experience demands endurance -- this is not a substance that allows coasting or passive observation.
The duration is exceptional. The peak plateau can last six to eight hours, and total effects may extend sixteen to twenty hours. The descent is painfully slow, with visual and cognitive effects lingering long past the point of welcome. Sleep is impossible for the duration. The aftermath includes profound fatigue, physical depletion, and often a need for a full day of recovery. For those with the fortitude to navigate its demands, 2C-P can deliver psychedelic experiences of remarkable depth and power -- but the price of admission is steep, measured in hours, physical endurance, and the willingness to surrender to a timeline that cannot be shortened.
Subjective Effects
The effects listed below are based on the Subjective Effect Index (SEI), an open research literature based on anecdotal reports and personal analyses. They should be viewed with a healthy degree of skepticism. 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.
Physical Effects
Physical(14)
- Bodily control enhancement— Bodily control enhancement is the subjective feeling of improved physical precision, coordination, a...
- Body load— A diffuse, heavy physical discomfort involving tension, pressure, and malaise in the torso and limbs...
- Increased blood pressure— Increased blood pressure (hypertension) is an elevation of arterial pressure above the normal 120/80...
- Increased bodily temperature— Increased bodily temperature (hyperthermia) is an elevation of core body temperature above the norma...
- Increased heart rate— A noticeable acceleration of heartbeat that can range from a subtle awareness of one's pulse to a fo...
- Increased libido— A marked enhancement of sexual desire, arousal, and sensitivity to erotic stimuli that can range fro...
- Muscle tension— Persistent partial contractions or tightening of muscles that produces uncomfortable stiffness, cram...
- Nausea— An uncomfortable sensation of queasiness and stomach discomfort that may or may not lead to vomiting...
- Physical euphoria— An intensely pleasurable bodily sensation that can manifest as waves of warmth, tingling electricity...
- Pupil dilation— A visible enlargement of the pupil diameter (mydriasis) that can range from subtle widening to drama...
- Stimulation— A state of heightened physical and mental energy characterized by increased wakefulness, elevated mo...
- Teeth grinding— An involuntary clenching and rhythmic grinding of the jaw muscles, known clinically as bruxism, that...
- Temperature regulation disruption— Impaired thermoregulation causing unpredictable fluctuations between feeling hot and cold, with risk...
- Vasoconstriction— A narrowing of blood vessels throughout the body that produces sensations of cold extremities, tingl...
Tactile(1)
- Tactile enhancement— The sense of touch becomes dramatically heightened, making physical contact feel intensely pleasurab...
Cognitive & Perceptual Effects
Visual(16)
- After images— A visual phenomenon in which a faint, ghostly imprint of a previously viewed image persists in the v...
- Autonomous entity— The perception of contact with seemingly sentient, independently acting beings that appear within ha...
- Colour enhancement— An intensification of the brightness, vividness, and saturation of colors in the external environmen...
- Depth perception distortions— Alterations in how the distance of objects within the visual field is perceived, causing layers of s...
- Drifting— The visual experience of perceiving stationary objects, textures, and surfaces as appearing to flow,...
- Geometry— The experience of perceiving complex, ever-shifting geometric patterns superimposed over the visual ...
- Internal hallucination— Vivid, detailed visual experiences perceived within an imagined mental landscape that can only be se...
- Pattern recognition enhancement— An increased ability and tendency to perceive meaningful patterns, faces, and images within ambiguou...
- Perspective hallucination— A hallucinatory phenomenon in which the observer's visual perspective shifts from the normal first-p...
- Scenery slicing— The visual field fractures into distinct, cleanly cut sections that slowly drift apart from their or...
- Settings, sceneries, and landscapes— The perceived environment in which hallucinatory experiences take place, ranging from recognizable l...
- Symmetrical texture repetition— Textures appear to mirror and tessellate across surfaces in intricate, self-similar symmetrical patt...
- Tracers— Moving objects leave visible trails of varying length and opacity behind them, similar to long-expos...
- Transformations— Objects and scenery undergo perceived visual metamorphosis, smoothly shapeshifting into other recogn...
- Unspeakable horrors— A deeply distressing hallucinatory state involving sustained exposure to nightmarish, terrifying, an...
- Visual acuity enhancement— Vision becomes sharper and more defined than normal, as though a slightly blurry lens has been broug...
Cognitive(17)
- Analysis enhancement— A perceived improvement in one's ability to logically deconstruct concepts, recognize patterns, and ...
- Autonomous voice communication— Autonomous voice communication is the experience of hearing and engaging in conversation with one or...
- Conceptual thinking— A shift in the nature of thought from verbal, linear sentence structures to intuitive, non-linguisti...
- Creativity enhancement— An increase in the ability to imagine new ideas, overcome creative blocks, think about existing conc...
- Delirium— Delirium is a serious and potentially dangerous state of acute mental confusion involving disorienta...
- Delusion— A delusion is a fixed, false belief that is held with unshakeable certainty and is impervious to con...
- Immersion enhancement— A heightened capacity to become fully absorbed and engrossed in external media such as music, films,...
- Introspection— An enhanced state of self-reflective awareness in which one feels drawn to examine their own thought...
- Memory suppression— A dose-dependent inhibition of one's ability to access and utilize short-term and long-term memory, ...
- Multiple thought streams— The experience of having more than one internal narrative or stream of consciousness simultaneously ...
- Novelty enhancement— A feeling of increased fascination, awe, and childlike wonder attributed to everyday concepts, objec...
- Personal bias suppression— A decrease in the personal, cultural, and cognitive biases through which one normally filters their ...
- Personal meaning enhancement— Personal meaning enhancement is a state in which everyday events, coincidences, song lyrics, environ...
- Thought acceleration— The experience of thoughts occurring at a dramatically increased rate, as if the mind has been shift...
- Thought loops— Becoming trapped in a repeating cycle of thoughts, actions, and emotions that loops every few second...
- Time distortion— Subjective perception of time becomes dramatically altered — minutes may feel like hours, or hours p...
- Wakefulness— An increased ability to stay awake and alert without the desire to sleep. Distinct from stimulation ...
Multi-sensory(2)
- Machinescapes— Machinescapes are complex multisensory hallucinations involving the perception of enormous mechanica...
- Scenarios and plots— Scenarios and plots are the narrative structures that emerge within hallucinatory states — coherent ...
Transpersonal(5)
- Ego death— A profound dissolution of the sense of self in which personal identity, memories, and the boundary b...
- Entity contact— Perception of encountering autonomous beings or presences during psychedelic states, ranging from va...
- Perception of interdependent opposites— Perception of interdependent opposites is the profound, felt realization that reality is structured ...
- Spirituality enhancement— A profound intensification of spiritual feelings, mystical awareness, and a sense of sacred connecti...
- Unity and interconnectedness— A profound sense that identity extends beyond the self to encompass other people, nature, or all of ...
Pharmacology
Mechanism of Action
2C-P acts as a partial agonist at serotonin 5-HT2A receptors, sharing the primary mechanism of all 2C compounds. The 4-propyl substituent — a three-carbon alkyl chain — produces unusually high receptor affinity compared to shorter-chain analogs. The propyl chain's length and flexibility appear to allow optimal hydrophobic interactions within the 5-HT2A binding pocket, conferring potency considerably greater than 2C-E (4-ethyl) or any halogen-substituted 2C compound.
Exceptional Potency
The 4-propyl group makes 2C-P one of the most potent orally active phenethylamine psychedelics known. The active threshold is approximately 4–6 mg — roughly half the threshold dose of 2C-B. This places it in a category where milligram-scale dosing errors carry consequences measured in orders of magnitude of effect.
Why the Onset Is Slow
The slow onset (1.5–3 hours) of 2C-P relative to other 2C compounds likely reflects the lipophilicity of the propyl chain. The compound's higher lipophilicity compared to halogen-substituted analogs means it may accumulate in tissue compartments before equilibrating in the CNS, delaying the onset while ultimately producing a longer and more intense experience than predicted by initial come-up rate.
Duration
The 12–20 hour duration of 2C-P is extraordinary for an orally active phenethylamine and appears related to both its receptor affinity (longer receptor occupancy) and the metabolic stability of the propyl group, which resists oxidative metabolism more than the shorter ethyl chain.
Tolerance
Cross-tolerance with other serotonergic psychedelics is expected. At the doses involved, tolerance should be fully respected — use with an interval of at least 2 weeks is prudent.
Detection Methods
Urine Detection
2C-P is not specifically targeted by standard immunoassay-based urine drug panels. However, because 2C-x phenethylamines share structural features with amphetamines, they may trigger false positives on amphetamine immunoassays in some cases. The likelihood of cross-reactivity depends on the specific immunoassay manufacturer and the antibody selectivity used. Urine detection windows for 2C-P are estimated at 24 to 72 hours following ingestion when analyzed by LC-MS/MS methods, though limited pharmacokinetic data exists for many 2C-x compounds.
Blood and Serum Detection
Blood detection windows for 2C-P are approximately 6 to 24 hours after oral administration. Peak plasma concentrations typically occur 1 to 3 hours post-ingestion. The relatively short half-lives of most 2C-x phenethylamines mean that blood testing must be performed promptly to capture detectable concentrations. LC-MS/MS is the only reliable method for quantitative blood analysis.
Standard Drug Panel Inclusion
2C-P is NOT specifically included on standard 5-panel, 10-panel, or 12-panel drug screens. The primary concern for individuals undergoing routine screening is the potential for amphetamine cross-reactivity on immunoassay-based panels. If a presumptive positive for amphetamines occurs, confirmatory testing by GC-MS or LC-MS/MS would not confirm amphetamine and the result would be reported as negative unless the laboratory specifically tests for 2C-x compounds. Most routine laboratories do not include 2C-x phenethylamines in their confirmatory panels.
Confirmatory Methods
Definitive identification of 2C-P requires LC-MS/MS or GC-MS with appropriate reference standards. Some forensic toxicology laboratories include 2C-x phenethylamines in their extended novel psychoactive substance panels. Immunoassay cross-reactivity alone is insufficient for confirmation and would be resolved by standard confirmatory procedures. Quantitative analysis typically requires specific method development as these compounds are not part of routine clinical chemistry workflows.
Reagent Testing (Harm Reduction)
For harm reduction identification, the Marquis reagent is a primary screening tool for 2C-P. The Marquis reagent produces a green to dark green reaction with 2C-P. Due to the high potency and long duration of 2C-P, correct identification is particularly important. The Mecke reagent may provide additional color reactions that help differentiate between specific 2C-x variants. The Ehrlich reagent shows no reaction with 2C-x phenethylamines, which can help distinguish them from tryptamines and lysergamides. The Mandelin reagent may produce green to brown reactions depending on the specific compound. Using multiple reagents in combination provides the most reliable field identification, though reagent testing cannot determine purity or dosage.
Interactions
| Substance | Status | Note |
|---|---|---|
| 3-FMA | Caution | Increases anxiety, cardiovascular stress, and psychological intensity |
| 4-MMC | Caution | Increases anxiety, cardiovascular stress, and psychological intensity |
| 8-Chlorotheophylline | Caution | Increases anxiety, cardiovascular stress, and psychological intensity |
| Adrafinil | Caution | Increases anxiety, cardiovascular stress, and psychological intensity |
| Anandamide | Caution | Cannabis can unpredictably intensify psychedelic effects and increase anxiety |
| Cannabis | Uncertain | — |
| 1,3-Butanediol | Low Risk & Synergy | Cross-tolerance exists; effects compound |
| 25E-NBOH | Low Risk & Synergy | Cross-tolerance exists; effects compound |
| 2C-T | Low Risk & Synergy | Cross-tolerance exists; effects compound |
| 2C-T-2 | Low Risk & Synergy | Cross-tolerance exists; effects compound |
History
Development and PiHKAL
2C-P was synthesized by Alexander Shulgin as part of his 4-substituted 2,5-dimethoxyphenethylamine series, representing the 4-propyl member of the alkyl-substituted branch alongside 2C-E (ethyl) and 2C-M (methyl). Shulgin documented it in PiHKAL (1991) with notable language about its extreme potency and long duration, rating it "perhaps the most effective [of the 2C series] on a per-milligram basis." His bioassay records indicate he found 2C-P to be a demanding compound requiring careful respect.
Research Chemical Era and Adverse Events
2C-P became available through research chemical vendors in the mid-to-late 2000s. Unlike the more commercially prominent 2C-B, 2C-I, and 2C-E, 2C-P occupied a niche market of experienced users seeking extreme experiences. However, adverse events associated with dosing errors accumulated and were documented in harm reduction forums and medical literature, establishing its reputation as the most hazardous of the widely available 2C compounds.
Documented Case Reports
Medical literature contains multiple published case reports of severe adverse events associated with 2C-P, including at least one fatal case. These cases uniformly involve doses substantially above the threshold range and often involve the "slow onset redosing" error pattern.
Legal Status
2C-P is Schedule I in the United States. It is controlled in most European and other jurisdictions under phenethylamine scheduling frameworks.
Harm Reduction
Strong Warning: Not Recommended for Most Users
2C-P is not suitable for psychedelic beginners, individuals with cardiovascular conditions, or those without significant experience managing challenging psychedelic experiences. The risk/reward calculus is unfavorable compared to other 2C compounds.
Dosing — Start Extremely Low
- Threshold: ~3–5 mg | Light: 5–7 mg | Common: 7–12 mg | Strong: 12+ mg (do not approach without extensive experience)
- Treat 5 mg as a full dose for a first experience
- Use a precision milligram scale — this is non-negotiable
Never Redose
The slow onset (1.5–3 hours) has caused many severe adverse events. Do not redose under any circumstances based on a slow onset. Wait the full 3 hours before drawing any conclusions about effect onset. The dose is working.
Sober Trip Sitter is Mandatory
Given the extreme duration and potential for overwhelming effects, a dedicated, sober, informed trip sitter must be present for the entire duration of any 2C-P experience.
Plan for a Full Day
Minimum 20–24 hours from dosing to return to baseline functionality. Do not use before work, important appointments, or situations requiring driving or competent decision-making the next day.
Dangerous Combinations
Toxicity & Safety
Extreme Caution Required
2C-P is one of the most hazardous common research chemical psychedelics from a practical standpoint, not because of unusual organ toxicity but because of the conditions it creates for severe adverse events:
- Extreme potency — A small absolute dosing error (3–4 mg too much) translates to a dramatically different experience
- Slow onset — Users have repeatedly redosed, believing their initial dose was inactive, producing profound overdose
- Very long duration — A severe adverse event at 2C-P doses may require 12–20 hours of medical management
Documented Fatality
At least one death has been attributed to 2C-P use in the published literature. The case involved extreme doses and is consistent with psychedelic-associated cardiovascular and thermoregulatory failure rather than any unique organ toxicity of 2C-P itself.
Cardiovascular
The significant stimulant component at typical doses produces meaningful sympathomimetic effects — tachycardia, hypertension, hyperthermia — that persist over the very long duration of effect. Cardiovascular stress over 12–20 hours represents a substantially greater burden than with a 4–6 hour psychedelic.
Hyperthermia Risk
Thermoregulatory dysregulation with extreme hyperthermia is a documented risk at high doses. Physical activity during a 2C-P experience significantly amplifies this risk.
Psychological
The extreme intensity and duration of a high-dose 2C-P experience is psychologically traumatic for many users. Lasting integration difficulties, PTSD-like responses to the experience, and exacerbation of pre-existing mental health conditions are meaningfully more likely than with shorter-acting compounds.
Drug Interactions
Addiction Potential
low potential for abuse and dependence
Overdose Information
Overdose
The LD50 of 2C-P has not been established. However, it is believed that 2C-P is likely to have a smaller therapeutic window compared to other 2C's, meaning a lethal dose may be achieved more easily.
In 2017, a 25-year old British female died following the ingestion of a large dose of 2C-P at a music festival. No source reported clear evidence that 2C-P by itself led to the immediate death of the female.
As a serotonergic psychedelic, 2C-low potential for abuse and dependence.
Tolerance to the effects of 2C-almost immediately after ingestion. After that,37 days to be back at baseline (in the absence of further consumption). 2C-P produces cross-tolerance with Cross-all psychedelics, meaning that after the consumption of 2C-P all psychedelics will have a reduced effect.
2C-P is not scheduled under the UN Convention on Psychotropic Substances. It is considered to exist in a legal grey area in many countries, meaning that while it is not specifically illegal, individuals may still be charged for its possession under certain circumstances such as under analogue laws and with the intent to sell or consume.
- Austria: 2C-P is illegal to possess, produce and sell under the NPSG (Neue-Psychoaktive-Substanzen-Gesetz Österreich). In its Schedule II, the further specifying NPSV (Neue-Psychoaktive-Substanzen-Verordnung Österreich) explicitly bans all substituted phenetylamines.
- Canada: 2C-P would be considered Schedule III as it is a derivative of 2,5-dimethoxyphenethylamine.
- China: As of October 2015, 2C-P is a controlled substance in China.
- Denmark: 2C-P is on the list of Schedule B controlled substances.
- Germany: 2C-P is controlled under Anlage I BtMG (*Narcotics Act, Sche
Tolerance
| Full | almost immediately after ingestion |
| Half | 3 days |
| Zero | 7 days |
Cross-tolerances
Legal Status
2C-P is not scheduled under the UN Convention on Psychotropic Substances. It is considered to exist in a legal grey area in many countries, meaning that while it is not specifically illegal, individuals may still be charged for its possession under certain circumstances such as under analogue laws and with the intent to sell or consume.
Austria: 2C-P is illegal to possess, produce and sell under the NPSG (Neue-Psychoaktive-Substanzen-Gesetz Österreich). In its Schedule II, the further specifying NPSV (Neue-Psychoaktive-Substanzen-Verordnung Österreich) explicitly bans all substituted phenetylamines.
Canada: 2C-P would be considered Schedule III as it is a derivative of 2,5-dimethoxyphenethylamine.
China: As of October 2015, 2C-P is a controlled substance in China.
Denmark: 2C-P is on the list of Schedule B controlled substances.
Germany: 2C-P is controlled under Anlage I BtMG (Narcotics Act, Schedule I) as of December 13, 2014. It is illegal to manufacture, possess, import, export, buy, sell, procure or dispense it without a license.
Japan: 2C-P is a controlled substance in Japan effective March 25th, 2015.
Latvia: 2C-P is a Schedule I controlled substance.
Switzerland: 2C-P is a controlled substance specifically named under Verzeichnis E.
Turkey:** 2C-P is a classed as drug and is illegal to possess, produce, supply, or import.
The Netherlands:** 2C-P is currently legal, but it is part of a substance group that may be banned soon as part of a recently passed law on New Psychoactive Substances (NPS).
United Kingdom: 2C-P is a Class A drug in the United Kingdom as a result of the phenethylamine catch-all clause.
United States: 2C-P is a Schedule I controlled substance. This means 2C-P is illegal to manufacture, buy, possess, process, or distribute without a license from the Drug Enforcement Administration (DEA).
Responsible use
Volumetric liquid dosing
Research chemicals
Psychedelics
Phenethylamines
2C-P (Wikipedia)
2C-P (Erowid Vault)
2C-P (PiHKAL / Isomer Design)
Discussion
The Big & Dandy 2C-P Thread (Bluelight)
Experience Reports (1)
Tips (6)
2C-P has one of the steepest dose-response curves of any psychedelic. The difference between a moderate trip and an overwhelming experience can be as little as 2mg. Never exceed a common dose on your first attempt, and never redose within 3 hours due to the extremely slow onset.
Clear your schedule for the full duration of 2C-P plus afterglow. Do not plan any obligations, driving, or important decisions for the day. Having a time pressure or commitment hanging over you adds unnecessary anxiety.
2C-P is one of the longest lasting psychedelic phenethylamines, with effects persisting 10-16 hours at moderate doses. Clear your entire day and ideally the next morning as well. Do not take this substance if you have any time-sensitive obligations within 20 hours.
Start with a low dose of 2C-P if it is your first time. You can always take more next time but you cannot take less once ingested. The difference between a comfortable and an overwhelming experience can be surprisingly small.
Do not combine 2C-P with lithium (seizure risk), tramadol (seizure/serotonin syndrome risk), or cannabis at higher doses unless very experienced. Cannabis dramatically intensifies and can destabilize a psychedelic experience.
The body load from 2C-P is notably heavier than most other 2C compounds. Significant nausea, muscle tension, and vasoconstriction are commonly reported. Having magnesium supplements, ginger, and a warm blanket available can help manage the physical discomfort.
See Also
References (4)
- Psilocybin produces substantial and sustained decreases in depression and anxiety — Griffiths et al. Journal of Psychopharmacology (2016)paper
- Neural correlates of the LSD experience revealed by multimodal neuroimaging — Carhart-Harris et al. PNAS (2016)paper
- 2C-P - TripSit Factsheet
TripSit factsheet for 2C-P
tripsit - 2C-P - Wikipedia
Wikipedia article on 2C-P
wikipedia