CBD half-life
This profile models the roughly 56-to-61-hour terminal half-life reported after repeated oral Epidiolex administration.
Every curve begins at 100%. No dose or measured body concentration is assumed.
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.
CBD: evidence and interpretation notes
Distribution makes the headline complicated
This profile models the roughly 56-to-61-hour terminal half-life reported after repeated oral Epidiolex administration. It is deliberately labeled as a chronic oral pharmaceutical context, not a universal value for inhaled, single-dose, or nonprescription CBD products.
The calculator follows CBD after repeated oral Epidiolex dosing with a 58.5-hour half-life. That simplification is useful for curve shape and comparison, but it is not an individualized pharmacokinetic estimate.
CBD has a more complicated pharmacokinetic profile than a single half-life suggests. Formulation, food, route of administration, and chronic use can all shift exposure.
The 18 hour value gives the calculator a long cannabinoid curve, but cannabidiol literature often reports ranges and context-dependent estimates rather than one universal number.
The citations include a systematic pharmacokinetic review, the Epidiolex label, and the direct cannabidiol compound record.
This page does not compare consumer CBD products, recommend doses, or evaluate interactions. It only explains the displayed half-life model.
For CBD, tissue distribution and metabolite persistence are central caveats. A simple half-life curve should not be confused with detection windows or whole-body storage.
What each source contributes
- Millar SA et al. Systematic review on the pharmacokinetics of cannabidiol in humans (2018). This synthesis organizes the available literature and caveats and cannot replace checking the underlying study design.
- DailyMed: Epidiolex cannabidiol oral solution. This product label adds formulation-specific pharmacokinetic context and does not represent every route or product.
- PubChem: Cannabidiol. This identity record confirms names and compound identity and does not supply a human half-life.
For CBD, the numerical model is tied most closely to Millar SA et al. Systematic review on the pharmacokinetics of cannabidiol in humans (2018). As a synthesis, it organizes the available literature and caveats; it cannot replace checking the underlying study design.
Why the range stays visible
The 56-to-61-hour range is retained beside the 58.5-hour input for CBD after repeated oral Epidiolex dosing. 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 2.4 days as a representative input for CBD after repeated oral Epidiolex dosing. In the simplified model, about 75.2% remains after 24 hours and about 3% remains after five half-lives, or roughly 12 days.
This is a long-tail curve. The page is most useful for understanding persistence and accumulation concepts, not for making decisions from one percentage. The curve is relative: it does not estimate a person's measured concentration, effects, impairment, or time to clearance.
cannabinoid context
Cannabinoid kinetics can be complicated by tissue distribution, metabolites, route, frequency of use, and long detection windows.
- Detection windows are not the same as pharmacologic half-life.
- Single-dose curves can understate complexity after repeated exposure.
- Routes such as inhaled and oral use can produce different concentration-time profiles.
ComparisonTimeline checkpoints and nearby profiles
CBD timeline checkpoints
| Elapsed time | Modeled remaining | Reading note |
|---|---|---|
| 24 h | 75.2% | Early in the modeled curve |
| 3.0 days | 42.6% | Meaningful modeled decline, not near-zero |
| 5.0 days | 24.1% | Long-tail portion of the model |
| 7.0 days | 13.7% | Long-tail portion of the model |
| 14 days | 1.87% | Low modeled remainder, not a clearance guarantee |
Nearby profiles by half-life
These entries sit near CBD within the cannabinoid group when sorted by representative half-life. That makes them curve comparisons, not statements about equal potency, effects, or risk.
No nearby published profiles are available in this category.
EvidencePharmacokinetic inputs and source trail
Pharmacokinetics at a glance
| Representative half-life | 2.4 days |
|---|---|
| Modeled analyte or phase | CBD after repeated oral Epidiolex dosing |
| Reported range | 2.3 days to 2.5 days |
| Curve type | Normalized, first-order decline |
Selection note: This profile models the roughly 56-to-61-hour terminal half-life reported after repeated oral Epidiolex administration. It is deliberately labeled as a chronic oral pharmaceutical context, not a universal value for inhaled, single-dose, or nonprescription CBD products.
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.
- Research abstract Millar SA et al. Systematic review on the pharmacokinetics of cannabidiol in humans (2018).Direct pharmacokinetic context. Population, route, formulation, analyte, and sampling duration still determine how broadly the result can be applied.
- Official labeling DailyMed label: Epidiolex cannabidiol oral solution.Official U.S. product labeling used for formulation and labeled pharmacokinetic context; its statements apply to the described product.
- Identity record PubChem Compound Summary: Cannabidiol.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
- All substance profiles
- Browse the cannabinoid group
- Compare this curve
- Clearance and volume of distribution
- Bioavailability, route, and formulation
- Active metabolites and parent compounds
- First-order vs nonlinear kinetics
- Detection windows vs half-life
- Reading labels and source quality
Read the medical disclaimer, methodology, and research standards before using the model for comparison.