HalfLifeDBEvidence before certainty.

GBL evidence profile

GBL is rapidly converted to GHB, making precursor conversion and GHB kinetics more important than a single parent-GBL half-life.

Category: depressant · Updated: August 7, 2026

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

Model statusNo curve publishedCurrent sources do not support one defensible human input
Evidence boundarySource note onlyNo animal, forensic, mixture, or proxy value is presented as a human half-life
Model scopeNot modeledThe profile explains what the available records can and cannot establish
References3Linked studies, labels, reviews, or identity records described below

GBL: evidence and interpretation notes

Why HalfLifeDB does not plot GBL

GBL is rapidly converted to GHB, making precursor conversion and GHB kinetics more important than a single parent-GBL half-life. The cited reviews explain that relationship but do not justify a stand-alone first-order GBL curve.

GBL is best understood on this site as a precursor-related entry connected to GHB toxicology. It is rapidly converted in the body, so parent-compound half-life is not the whole story.

The citations include clinical toxicology reviews of GHB, GBL, and 1,4-butanediol plus the direct compound record.

The page does not provide use instructions, combination guidance, or emergency advice.

What each source contributes

  • Busardo FP et al. The clinical toxicology of GHB, GBL and 1,4-butanediol (2012). This supporting literature record adds compound-specific background and is used only within the limits of its design.
  • Zvosec DL et al. GBL and 1,4-butanediol: abused analogues of GHB (2004). This supporting literature record adds compound-specific background and is used only within the limits of its design.
  • PubChem: gamma-Butyrolactone. This identity record confirms names and compound identity and does not supply a human half-life.

For GBL, the decision to withhold a curve turns on the limits visible in Busardo FP et al. The clinical toxicology of GHB, GBL and 1,4-butanediol (2012). This supporting literature record adds compound-specific background, but it is used only within the limits of its design.

What evidence would change the page

Before GBL could move from an evidence note to a chart, a study would need serial human measurements of the parent compound after a defined route, enough sampling to characterize elimination, and a population narrow enough to label honestly. That is a different evidence package from Busardo FP et al. The clinical toxicology of GHB, GBL and 1,4-butanediol (2012).

InterpretationCategory context and evidence limits

depressant context

Depressant entries can be pharmacokinetically short while still raising practical interpretation questions about sedation, coordination, and combinations.

  • Half-life is not a safe-activity or impairment clock.
  • Repeated exposure and combinations are not modeled.
  • Clinical or emergency concerns should not be handled with a calculator.
EvidenceSource trail and model decision

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 Busardo FP et al. The clinical toxicology of GHB, GBL and 1,4-butanediol (2012).
    Supporting literature record. Its role and study design should be read from the linked source before applying any numerical finding.
  2. Research abstract Zvosec DL et al. GBL and 1,4-butanediol: abused analogues of GHB (2004).
    Supporting literature record. Its role and study design should be read from the linked source before applying any numerical finding.
  3. Identity record PubChem Compound Summary: gamma-Butyrolactone.
    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.