Endogenous GHB Threshold
Definition
Normal human blood GHB is 0.5-4 mg/L; urine 1-10 mg/L. Post-mortem fermentation can raise values to 20-50 mg/L. Forensic toxicologists typically use 10 mg/L blood as the exogenous interpretation cut-off in living subjects, with expert commentary required for borderline values.
- Normal blood GHB
- 0.5-4 mg/L
- Normal urine GHB
- 1-10 mg/L
- Post-mortem range
- 20-50 mg/L
- Living-subject blood cut-off
- Approx. 10 mg/L
Common questions
Why is post-mortem GHB interpretation especially difficult?+
GHB can be produced by microbial fermentation after death, so an elevated post-mortem level does not by itself distinguish ingestion from natural post-mortem production without considering sample site and time since death.
Why isn't a single blood cut-off always decisive?+
Individual variation, the site the sample was taken from, and time since ingestion all affect measured levels, so results near the cut-off need expert interpretation alongside the case circumstances rather than a strict pass or fail reading.
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