A Systematic Review of Medical Cannabinoids Dosing in Human

This systematic review assesses currently available clinical information on which cannabinoids and what range of doses have been used to achieve positive effects in a diversity of medical context.

The data were collected according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol guidelines. Inclusion criteria were articles that assessed administration of any cannabinoid to any clinical population, reported in the ClinicalTrials.gov or PubMed databases, that involved a comparison with other treatment or placebo and a result measurement to assess the effectiveness or ineffectiveness of the cannabinoid. Exclusion criteria were review or letter; articles not in the English language; not full-text articles; not a clinical trial, case report, case series, open-label trial, or pilot study; administration in animals, in vitro, or in healthy participants; cannabinoids administered in combination with other cannabinoids (except for cannabidiol [CBD] or tetrahydrocannabinol [THC]) or as whole cannabis extracts; no stated concentration; inhalation or smoke as a route of administration; and no results described. The articles were assessed by the risk of bias.

In total, 1668 articles were recovered, of which 55 studies met the inclusion criteria for 21 diseases. Positive effects were reported in clinical studies: 52% with THC (range, 0.01-0.5 mg/kg/d [0.62-31 mg/d]), 74% with CBD (range, 1-50 mg/kg/d [62-3100 mg/d]), 64% with THC-CBD (mean, 1:1.3 mg/kg/d [ratio, 1:1]), and 100% with tetrahydrocannabivarin (THCV) (0.2 mg/kg/d).

THC, CBD, and THCV can regulate activity in several pathologies. New studies of cannabinoids are highly encouraged because each patient is unique and requires a unique cannabinoid medication.