Bioavailability
The fraction of an administered dose that reaches systemic circulation in an active form. Varies substantially by route of administration for cannabinoids.
In Depth
Cannabinoid bioavailability varies dramatically by route: inhalation (11–45%), oral (6–20% due to first-pass metabolism and lipophilicity), sublingual (13–19%), and transdermal (<1% without permeation enhancers). The high variability in oral bioavailability makes dose standardization challenging. Food, particularly high-fat meals, significantly increases oral CBD and THC absorption. Inhalation provides the fastest onset (minutes) but shortest duration; oral provides slowest onset (30–120 min) but longest duration.
Related Terms
More in Research Methods
Randomized Controlled Trial (RCT)
The gold standard study design in clinical research. Participants are randomly assigned to treatment or control groups to minimize bias and establish causation.
Systematic Review
A structured synthesis of all available evidence on a specific research question, using predefined criteria to identify, evaluate, and summarize studies.
Meta-Analysis
A statistical technique that combines quantitative data from multiple studies to produce a pooled estimate of effect size with greater statistical power than any individual study.
Placebo-Controlled
A study design in which the control group receives an inert substance (placebo) identical in appearance to the active treatment, to account for the placebo effect.
Observational Study
A study in which researchers observe participants without intervening. Includes cohort studies, case-control studies, and cross-sectional surveys.