Zopiclone / Eszopiclone half-life

The zopiclone review reports a 3.5-to-6.5-hour terminal range for the racemate.

Category: sedative-hypnotic · Updated: August 7, 2026

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

Model status5 hZopiclone racemate · same-day representative value
Reported range3.5 h–6.5 hPublished 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.

0m5h10h15h20h25h0%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. The shaded band shows the reported half-life range. This is a mathematical visualization, not a personal concentration estimate.

Modeled remaining: 50.0%Half-life used: 5 h

Zopiclone / Eszopiclone: evidence and interpretation notes

What the representative value means

The zopiclone review reports a 3.5-to-6.5-hour terminal range for the racemate. Eszopiclone is related but distinct, so the plotted five-hour value is now labeled specifically as zopiclone rather than a combined-drug average.

For the interactive chart, HalfLifeDB starts with 5 hours as the representative value for Zopiclone racemate. Route, formulation, sampling, and metabolites remain attached to that label instead of being hidden inside the arithmetic.

Zopiclone and eszopiclone are grouped here because they are closely related sedative-hypnotics, but the page still uses one simplified curve.

The 5 hour value is a representative input, not a claim that every formulation, enantiomer, or patient follows the same timeline.

The citations include a clinical pharmacokinetics review for zopiclone, a direct eszopiclone label, and compound records for both zopiclone and eszopiclone.

The model does not estimate sleep benefit, residual impairment, or medication suitability.

For Zopiclone / Eszopiclone, a shorter half-life can still be relevant for next-day functioning. Age, dose, sleep timing, and co-medications can change real-world residual effects.

What each source contributes

  • Goa KL et al. Clinical pharmacokinetics of zopiclone (1995). This human pharmacokinetic record adds measured route, analyte, and population context and does not become a universal result.
  • DailyMed: Eszopiclone tablet. This product label adds formulation-specific pharmacokinetic context and does not represent every route or product.
  • PubChem: Zopiclone. This identity record confirms names and compound identity and does not supply a human half-life.
  • PubChem: Eszopiclone. This identity record confirms names and compound identity and does not supply a human half-life.

For Zopiclone / Eszopiclone, the numerical model is tied most closely to Goa KL et al. Clinical pharmacokinetics of zopiclone (1995). As a human pharmacokinetic record, it adds measured route, analyte, and population context; it does not become a universal result.

Why the range stays visible

The 3.5-to-6.5-hour range is retained beside the 5-hour input for Zopiclone racemate. It is not an uncertainty slider or a personalized prediction; it shows that the cited literature does not reduce to one invariant value.

InterpretationReading the curve and its category context

Reading this curve

HalfLifeDB uses 5 h as a representative input for Zopiclone racemate. In the simplified model, about 3.6% remains after 24 hours and about 3% remains after five half-lives, or roughly 25 h.

This sits in the same-day range. The chart is useful for seeing the bend of the curve across a day or two, but it should not be treated as a personal clock. The curve is relative: it does not estimate a person's measured concentration, effects, impairment, or time to clearance.

sedative-hypnotic context

Sedative-hypnotic half-life estimates may not reflect next-day impairment, active metabolites, or effects from combined central nervous system depressants.

  • Half-life does not equal safe timing for activities.
  • Combination effects are outside the calculator model.
  • Formulation and route can change onset and peak.
ComparisonTimeline checkpoints and nearby profiles

Zopiclone / Eszopiclone timeline checkpoints

Elapsed timeModeled remainingReading note
6 h43.5%Meaningful modeled decline, not near-zero
12 h18.9%Long-tail portion of the model
24 h3.59%Low modeled remainder, not a clearance guarantee
2.0 days0.13%Low modeled remainder, not a clearance guarantee
3.0 days0.00%Low modeled remainder, not a clearance guarantee

Nearby profiles by half-life

These entries sit near Zopiclone / Eszopiclone within the sedative-hypnotic 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-life5 h
Modeled analyte or phaseZopiclone racemate
Reported range3.5 h to 6.5 h
Curve typeNormalized, first-order decline

Selection note: The zopiclone review reports a 3.5-to-6.5-hour terminal range for the racemate. Eszopiclone is related but distinct, so the plotted five-hour value is now labeled specifically as zopiclone rather than a combined-drug average.

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.

1 PubMed0 PMC1 DailyMed2 PubChem
  1. Research abstract Goa KL et al. Clinical pharmacokinetics of zopiclone (1995).
    Direct pharmacokinetic context. Population, route, formulation, analyte, and sampling duration still determine how broadly the result can be applied.
  2. Official labeling DailyMed label: Eszopiclone tablet.
    Official U.S. product labeling used for formulation and labeled pharmacokinetic context; its statements apply to the described product.
  3. Identity record PubChem Compound Summary: Zopiclone.
    Compound identity and naming record. It supplies chemistry context, not independent numerical support for the model.
  4. Identity record PubChem Compound Summary: Eszopiclone.
    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.