PCP half-life

Human disposition studies show a wide and variable PCP half-life, with route and individual elimination contributing to the spread.

Category: dissociative · Updated: August 7, 2026

Sources and model notes are maintained by . This page is educational, not clinical guidance. Corrections: admin@halflifedb.co.

Model status21 hPCP · day-scale representative value
Reported rangeNot displayedPublished when the current evidence record supports a readable range
Model scopeRelative declineNormalized first-order model, not an in-body concentration estimate
References4Linked studies, labels, reviews, or identity records described below
Relative starting point
100%

Every curve begins at 100%. No dose or measured body concentration is assumed.

0m21h42h2.6d3.5d4.4d0%25%50%75%100%X-axis: elapsed timeY-axis: amount remaining (%)

X-axis: elapsed time. Y-axis: modeled percentage of the relative starting point remaining. This is a mathematical visualization, not a personal concentration estimate.

Modeled remaining: 50.0%Half-life used: 21 h

PCP: evidence and interpretation notes

The measured compound is only one timeline

Human disposition studies show a wide and variable PCP half-life, with route and individual elimination contributing to the spread. The 21-hour center is useful only while the broad source range remains in view.

The visual model centers on PCP at 21 hours. Nothing in the calculation adjusts for dose history, organ function, interactions, tolerance, or a study’s sampling method.

PCP is a dissociative with older but direct disposition studies, including work on different routes of exposure.

The 21 hour value gives PCP a long curve in the database. Published studies show route and distribution can complicate the shape beyond a simple one-compartment model.

The citations include disposition studies after oral, intravenous, and smoked exposure, StatPearls toxicity context, and the compound record.

The page does not estimate behavioral effects, violence risk, toxicity, or testing outcomes.

For PCP, parent-compound decline can differ from dissociation, sedation, analgesia, or motor effects. Metabolites and redistribution may also be relevant depending on the substance.

What each source contributes

  • Cook CE et al. Phencyclidine disposition after intravenous and oral doses (1982). This human pharmacokinetic record adds measured route, analyte, and population context and does not become a universal result.
  • Cook CE et al. Phencyclidine and phenylcyclohexene disposition after smoking PCP (1982). This human pharmacokinetic record adds measured route, analyte, and population context and does not become a universal result.
  • Phencyclidine Toxicity. StatPearls. This synthesis organizes the available literature and caveats and cannot replace checking the underlying study design.
  • PubChem: Phencyclidine. This identity record confirms names and compound identity and does not supply a human half-life.

For PCP, the numerical model is tied most closely to Cook CE et al. Phencyclidine disposition after intravenous and oral doses (1982). As a human pharmacokinetic record, it adds measured route, analyte, and population context; it does not become a universal result.

Why there is no range on the chart

This profile plots 21 hours for PCP without adding an unsourced high-low band. A single supported center is more honest than manufacturing a range from unrelated routes, populations, or formulations.

InterpretationReading the curve and its category context

Reading this curve

HalfLifeDB uses 21 h as a representative input for PCP. In the simplified model, about 45.3% remains after 24 hours and about 3% remains after five half-lives, or roughly 4.4 days.

This is a day-scale half-life. Repeated exposure, timing, and source context start to matter more than a single snapshot of the curve. The curve is relative: it does not estimate a person's measured concentration, effects, impairment, or time to clearance.

dissociative context

Dissociative entries often require care because parent compounds, metabolites, redistribution, and subjective duration may not move together.

  • The calculator does not model active metabolites separately.
  • Duration and half-life can diverge substantially.
  • Study values may depend on route and sampling window.
ComparisonTimeline checkpoints and nearby profiles

PCP timeline checkpoints

Elapsed timeModeled remainingReading note
12 h67.3%Meaningful modeled decline, not near-zero
24 h45.3%Meaningful modeled decline, not near-zero
2.0 days20.5%Long-tail portion of the model
3.0 days9.29%Low modeled remainder, not a clearance guarantee
5.0 days1.90%Low modeled remainder, not a clearance guarantee

Nearby profiles by half-life

These entries sit near PCP within the dissociative group when sorted by representative half-life. That makes them curve comparisons, not statements about equal potency, effects, or risk.

EvidencePharmacokinetic inputs and source trail

Pharmacokinetics at a glance

Representative half-life21 h
Curve typeNormalized, first-order decline

Selection note: Human disposition studies show a wide and variable PCP half-life, with route and individual elimination contributing to the spread. The 21-hour center is useful only while the broad source range remains in view.

Sources and evidence context

A linked record is not automatically proof of the displayed value. Study, labeling, review, and compound identity sources serve different purposes; notes below identify limitations when they are known.

2 PubMed0 PMC0 DailyMed1 PubChem
  1. Research abstract Cook CE et al. Phencyclidine disposition after intravenous and oral doses (1982).
    Direct pharmacokinetic context. Population, route, formulation, analyte, and sampling duration still determine how broadly the result can be applied.
  2. Research abstract Cook CE et al. Phencyclidine and phenylcyclohexene disposition after smoking PCP (1982).
    Direct pharmacokinetic context. Population, route, formulation, analyte, and sampling duration still determine how broadly the result can be applied.
  3. Clinical reference Phencyclidine Toxicity. StatPearls.
    Synthesis or clinical background source used to frame the evidence and its limits rather than to create a new measured value.
  4. Identity record PubChem Compound Summary: Phencyclidine.
    Compound identity and naming record. It supplies chemistry context, not independent numerical support for the model.
BoundariesWhat this page cannot answer and where to continue

What this page does not answer

  • It does not estimate impairment, intoxication, or fitness to drive.
  • It does not predict urine, blood, saliva, or hair test results.
  • It does not model repeated exposure, tolerance, withdrawal, or interactions.
  • It does not replace clinician, pharmacist, toxicologist, or emergency guidance.

Continue with context

Read the medical disclaimer, methodology, and research standards before using the model for comparison.