THC Loaded Into a Vaporizer Was Not the Same as THC Absorbed by Each Patient

forensic toxicology working group members October 31, 2026 Forensic Toxicology

The prescribed-flower study estimated THC from product strength and weighed flower, while warning that this was not each participant’s absorbed dose. The distinction matters when comparing cognitive effects with milligrams on a study table.

The nominal calculation used material and strength

Participants weighed prescribed flower for vaporization. The paper calculated a mean nominal THC amount of 48.49 mg from the flower’s weight and stated potency. This was an estimate of THC represented in the material, not a measured systemic amount.

Administration introduced additional variation

Participants consumed different numbers of balloons, and vaporizer temperatures varied. Inhalation technique, delivery efficiency and absorption also affected exposure. The authors explicitly cautioned that the calculation did not fully account for these factors. A large nominal value should not be treated as an intravenous-equivalent amount.

Exposure-response comparisons need compatible quantities

A comparison with an oral dose or another inhalation study must preserve whether the number refers to loaded, delivered or absorbed drug. A nominal dose can help describe the protocol without locating a participant on a precise blood concentration-effect curve. This uncertainty does not erase the observed cognitive findings, but limits assigning them a universal milligram threshold. It also prevents a study-average amount from becoming a dosing recommendation or an individualized impairment rule.

Related analysis: the study’s main findings and limitations.