Abuse Liability of Triazolam: Experimental Measurements in Animals and Humans

Abstract

Drug abuse liability refers to: (a) the liability for abuse (i.e., the likelihood that a drug will be abused) and/or (b) the liability of abuse (i.e., the untoward effects of abusing the drug). These two senses of abuse liability correspond directly to two major characteristics of drugs of abuse: (a) they have reinforcing properties (they have the capacity to maintain drug self-administration) and (b) they produce adverse effects (they have the capacity to harm the individual and/or society). The presence of both characteristics is necessary to define a drug of abuse. A drug devoid of reinforcing effects but producing significant adverse effects should be considered a poison, not a drug of abuse (e.g., cyanide). Similarly, a drug having some reinforcing properties but producing no adverse effects is not meaningfully considered a drug of abuse (e.g., a nontoxic, non-nutritive sweetener). The relative abuse liability of a compound is a positive interactive function of the degree of reinforcing properties and adverse effect. Thus, compounds with high abuse liability could be: (a) highly efficacious reinforcers producing highly significant adverse effects (e.g., phencyclidine); (b) equivocal reinforcers producing highly significant adverse effects (e.g., lysergic acid diethylamide); or (c) highly efficacious reinforcers producing modest adverse effects (e.g., moderate cocaine doses). Compounds with low abuse liability must necessarily be those which are marginal reinforcers and produce marginal adverse effects (e.g., caffeine).