The Saber THC Score: A Route-Adjusted Quantitative Metric for Standardizing Cannabis Exposure

Background. Clinical assessment of cannabis use is inconsistent and lacks a standardized exposure metric comparable to Standard Drinks or Pack-Years. Variation in THC potency, route of delivery, and bioavailability complicates interpretation and cross-patient comparison. Objective. To describe the Saber THC Score, a route-adjusted framework that converts heterogeneous cannabis use patterns into monthly Saber Units (SU), where 1 SU is defined as the estimated systemic psychoactive burden of a 10 mg oral THC edible. Methods. A model-development approach integrated published evidence on THC bioavailability, first-pass metabolism to 11-hydroxy-THC (11-OH-THC), product potency, and route-specific systemic exposure. Route-specific conversion factors were derived from median published bioavailability estimates combined with a metabolite-adjusted potency factor, with the relative potency of 11-OH-THC set at 1.5 and examined across a sensitivity range of 1.0 to 5.0. Candidate SU thresholds were positioned against epidemiologic associations involving cannabis use disorder (CUD), withdrawal, psychiatric outcomes, cannabinoid hyperemesis syndrome (CHS), cognitive effects, and perioperative considerations. A free online calculator was developed to support clinical use. Results. The framework standardizes exposure across oral, oromucosal, smoked, vaporized, and concentrated routes, yielding an estimated daily systemic THC-equivalent burden, a monthly SU total, and a 0-10 Saber Score. Net conversion multipliers range from 0.150 (oral edibles) to 0.510 (concentrates) of input THC mass, and the relative weighting of oral versus inhaled routes is sensitive to the potency parameter. Proposed thresholds correspond to regular daily use (Score 4), heavy exposure relevant to CHS and psychiatric associations (Score 5-6), and very high-potency or concentrated use (Score 7 and above). Conclusions. The Saber THC Score offers a quantitative structure for documenting THC exposure that may support risk stratification and perioperative planning. The model is conceptual and has not been validated against any clinical outcome, and its thresholds are proposed rather than empirically derived. Validation studies are required before any clinical use.