Phase 1 Trial of CBD-Dominant Cannabis Oil Found It Safe with Dose-Proportional Absorption | Research

The takeaway

A Phase 1 trial of CBD-dominant cannabis oil (120-480 mg CBD daily) in 43 healthy participants found nearly all side effects were mild to moderate, CBD absorption was dose-proportional, and no consistent subjective effects were reported.

Physicians prescribing medical cannabis; pharmacologists; patients interested in CBD dosing science.

Recommended starting dose: ≤240 mg CBD + 10.8 mg THC daily in divided doses

What the researchers found

CBD showed dose-proportional absorption (AUC slope=1.03, Cmax slope=0.92). Steady-state was reached by Day 7. Nearly all adverse events (44/45) were mild or moderate; none serious. The highest adverse event rates (67%) occurred in the two higher-dose groups. Most THC concentrations were below detection limits.

Why it matters

Proper dosing information for cannabis products is severely lacking. This is one of the first rigorous Phase 1 pharmacokinetic studies of a standardized cannabis oil, providing the kind of data physicians need to make informed dosing decisions.

The numbers in context

43 participants. Doses: 120-480 mg CBD daily (with 5.4-21.6 mg THC). Adverse events: 44/45 mild-moderate, 0 serious. Highest AE rate: 67% in top two dose groups. Most AEs on first treatment day (17/45). CBD AUC slope: 1.03 (dose-proportional). Recommended starting dose: no higher than 240 mg CBD/10.8 mg THC daily.

How the study worked

Phase 1, multiple-dose, randomized, placebo-controlled study. 43 healthy participants received one of four CBD doses (120-480 mg/day with corresponding THC 5.4-21.6 mg/day) or placebo, administered every 12 hours for 7 consecutive days.

What this study cannot tell us

Conducted in healthy participants, so results may differ in patient populations. Seven-day duration is short relative to typical medical cannabis use. The product contained both CBD and THC, so effects cannot be attributed to CBD alone.

How to read the evidence

Moderate: randomized, placebo-controlled Phase 1 design, but small sample and conducted in healthy participants only.

When this study was published

Published in 2022.

The bigger picture

This represents the type of pharmaceutical-grade research that cannabis medicine has long needed. By providing PK/PD data comparable to standard drug development, it helps bridge the gap between patient use and evidence-based medicine.

Questions still open

Would the pharmacokinetic profile differ in patients with liver disease or those taking medications that affect CBD metabolism? What happens with longer-term use beyond 7 days? How does food intake affect absorption?

Common questions

What is a safe starting dose for CBD oil?

This study recommended starting at no higher than 240 mg total CBD and 10.8 mg total THC daily in divided doses, with gradual upward titration based on tolerability. Higher doses had more side effects, especially on the first day.

Did participants get high from the CBD oil?

No consistent subjective effects were reported between placebo and active treatment groups, and most THC blood levels were below detection limits, suggesting the CBD-dominant formulation did not produce noticeable intoxication.

Read the original research

Safety, Pharmacokinetics and Pharmacodynamics of Spectrum Yellow Oil in Healthy Participants.

Journal of analytical toxicology, 46(4), 393-407

View on PubMed ↗Publisher’s paper ↗

Citation

Peters, Erica N; Mosesova, Irina; MacNair, Laura; Vandrey, Ryan; Land, M Hunter; Ware, Mark A; Turcotte, Cynthia; Bonn-Miller, Marcel O. (2022). Safety, Pharmacokinetics and Pharmacodynamics of Spectrum Yellow Oil in Healthy Participants.. Journal of analytical toxicology, 46(4), 393-407. https://doi.org/10.1093/jat/bkab026