Heart Rate and Systolic Pressure Responded Differently to Inhaled THC

forensic toxicology working group members October 31, 2026 Forensic Toxicology

Heart rate and systolic blood pressure did not show the same pattern in the inhaled-cannabis trial. A significant response in one cardiovascular measure should not be reported as a uniform change in all vital signs.

A controlled human comparison

Seventeen adults with no cannabis use during the preceding month completed smoked and vaporized cannabis sessions containing 0, 10 or 25 mg THC. Researchers measured seated heart rate and blood pressure with an automated monitor.

Heart-rate increases were significantly greater than placebo after 25 mg smoked cannabis and after both active vaporized doses. At 10 mg, the heart-rate increase was significantly larger after vaporization than smoking.

The pressure result was not a matching dose pattern

Systolic pressure decreased significantly relative to placebo after the 10 mg smoked dose. The report did not find significant systolic-pressure differences across the vaporized doses. That is a different pattern from the heart-rate findings.

A nonsignificant pressure comparison does not establish that every individual’s pressure stayed unchanged. Conversely, a statistically significant group heart-rate effect does not establish a clinical cardiovascular event or an individualized impairment diagnosis.

Keep the endpoints and population attached

The measured outcomes were short-term seated vital signs in a small healthy sample. They do not describe every cannabis product, frequent user or patient with cardiovascular disease. The acute-effects and pharmacokinetic articles report the same experiment. The study’s corrected table title identifies peak changes from baseline, which need not all occur at the same assessment time.