Do consumers substitute opium for hashish? An economic analysis of simultaneous cannabinoid and opiate consumption in a legal regime

Abstract

Aim To analyze interrelationships in the consumption of opiates and cannabinoids in a legal regime and, specifically, whether consumers of opiates and cannabinoids treat them as substitutes for each other. Method Econometric dynamic panel data models for opium consumption are estimated using the generalized method of moments (GMM). A unique dataset containing information about opiate (opium) consumption from the Punjab province of British India for the years 1907–1918 is analyzed (n=272) as a function of its own price, the prices of two forms of cannabis (the leaf (bhang), and the resin (charas, or hashish)), and wage income. Cross-price elasticities are examined to reveal substitution or complementarity between opium and cannabis. Results Opium is a substitute for charas (or hashish), with a cross price elasticity (β3) of 0.14 (p < 0.05), but not for bhang (cannabis leaves; cross price elasticity = 0.00, p > 0.10). Opium consumption (β1 = 0.47 to 0.49, p < 0.01) shows properties of habit persistence consistent with addiction. The consumption of opium is slightly responsive (inelastic) to changes in its own price (β2 = −0.34 to −0.35, p < 0.05 to 0.01) and consumer wages (β4 = 0.15, p < 0.05). Conclusion Opium and hashish, a form of cannabis, are substitutes. In addition, opium consumption displays properties of habit persistence and slight price and wage income responsiveness (inelasticity) consistent with an addictive substance.

Societal issues and policy implications related to the use of cannabinoids, cannabis, and cannabis-based medicines for pain management

“…78 Although some preclinical and clinical evidence suggest opioid-sparing effects of cannabinoids, or analgesic synergy between the 2 classes of drugs, 18,41,76 one concern is that people merely substitute one addictive substance with another. 14 In addition, despite pharmacological differences between opioids and cannabinoids (notably overdose risk), there are nevertheless concerning similarities between the economic forces and public health messaging of perceived safety that fueled the opioid epidemic in North America, and those that drive the global expansion of medicinal cannabis use, without the appropriate evidence of long-term efficacy and safety. 28 The relationship between access to cannabis and opioid prescription rates remains circumstantial, and the clinical relevance of synergistic analgesia is currently conjectural, requiring further data at the population level.…”

Preclinical Studies of Cannabinoid Reward, Treatments for Cannabis Use Disorder, and Addiction-Related Effects of Cannabinoid Exposure

“…For example, the general strategy of seeking and taking a drug for its rewarding effects could facilitate trying other drugs. When cannabis becomes expensive or unavailable, users may switch to another class of drug as a substitute (Chandra and Chandra, 2015). The response topography used in smoking or injecting one drug could be transferred to another drug.…”