Initial development of a brief assessment of cocaine demand.

Cocaine demand is a behavioral economic measure assessing drug reward value and motivation to use drug. The purpose of the current study was to develop a brief assessment of cocaine demand (BACD). Results from the BACD were compared with self-report measures of cocaine use. Participants consisted of treatment-seeking individuals with cocaine use disorder (N = 22). Results revealed that indices of brief demand were significantly associated with various self-report measures of cocaine use. Overall, these results support the utility of a BACD for assessing cocaine demand.

Economic demand predicts addiction-like behavior and therapeutic efficacy of oxytocin in the rat.

Development of new treatments for drug addiction will depend on high-throughput screening in animal models. However, an addiction biomarker fit for rapid testing, and useful in both humans and animals, is not currently available. Economic models are promising candidates. They offer a structured quantitative approach to modeling behavior that is mathematically identical across species, and accruing evidence indicates economic-based descriptors of human behavior may be particularly useful biomarkers of addiction severity. However, economic demand has not yet been established as a biomarker of addiction-like behavior in animals, an essential final step in linking animal and human studies of addiction through economic models. We recently developed a mathematical approach for rapidly modeling economic demand in rats trained to self-administer cocaine. We show here that economic demand, as both a spontaneous trait and induced state, predicts addiction-like behavior, including relapse propensity, drug seeking in abstinence, and compulsive (punished) drug taking. These findings confirm economic demand as a biomarker of addiction-like behavior in rats. They also support the view that excessive motivation plays an important role in addiction while extending the idea that drug dependence represents a shift from initially recreational to compulsive drug use. Finally, we found that economic demand for cocaine predicted the efficacy of a promising pharmacotherapy (oxytocin) in attenuating cocaine-seeking behaviors across individuals, demonstrating that economic measures may be used to rapidly identify the clinical utility of prospective addiction treatments.

Costs and Effectiveness of Treating Homeless Persons with Cocaine Addiction with Alternative Contingency Management Strategies.

BACKGROUND: Between 1990 and 2006 in Birmingham, Alabama USA, 4 separate randomized controlled studies, called "Homeless 1" through "Homeless 4", treated cocaine substance abuse among chronically homeless adults, largely black men, many with non-psychotic mental health problems. The 4 studies had 9 treatment arms that used various counseling methods plus, in some arms, the provision of housing and work therapy usually with a contingent requirement of urine-test verified abstinence from substances. Participants in the abstinent-contingent arms who lapsed on abstinence were removed from housing and sent to an evening public shelter from which they were daily transported to day treatment until they returned to abstinence. AIMS OF THE STUDY: This paper compares the cost effectiveness of the treatment arms. METHODS: Societal cost per participant (in 2014 dollars) for each arm is defined as direct treatment cost plus cost of jail or hospital plus societal expense of public shelter use by lapsed participants. An untreated Base Case is defined as 5 percent abstinence with 95 percent usage of a public shelter. Incremental Cost Effectiveness Ratios (ICERs) for paired arms are defined as the change in cost per participant divided by the change in abstinence. Bootstrapping estimates confidence intervals. RESULTS: Average cost per participant at the end of 6 months of active treatment in 7 arms with comparable data ranged from USD 10,447 to USD 36,194 with corresponding average weeks abstinent ranging from 6.1 to 15.3 out of a possible 26 weeks. In contrast, the Base Case would cost USD 6,123 for 1.3 weeks of abstinence. Compared to the Base Case, the least expensive "DT2" treatment has an ICER of USD 901 (95% CI = USD 571 to USD 1,681) per additional week of abstinence and the most expensive "CMP4" has an ICER of USD 2,147 (95% CI = USD 1,701 to USD 2,848). Additionally, the Homeless 3 study found that the abstinent contingent housing (ACH3) treatment compared to the Non Abstinent Contingent Housing (NAC3), analogous to "Housing First", achieved better abstinence (12.1 v. 10 weeks) at higher average cost (USD 22,512 v. USD 17,541) yielding an ICER for this comparison of (USD 2,367, 95% CI=USD -10,587 to USD 12,467). Similar results are found at 12 months (6 months after active treatment). DISCUSSION: More intensive methods of counseling improved abstinence but 4 of the 7 treatments were inefficient ("dominated"). Bootstrapping shows that results are sensitive to which individuals were randomly assigned to each arm. A limitation of the analysis is that it does not consider the full societal cost of lost wages, crime costs beyond jail expenses and deterioration of neighborhood quality of life. Additionally, populations treated by Housing First programs may differ from the Birmingham Homeless studies in the severity of addiction or co-occuring psychological problems. IMPLICATIONS FOR TREATMENT: The Homeless studies show that abstinent contingent safe housing with counseling can substantially improve abstinence for homeless cocaine abusers. Incremental costs rise sharply with more intensive counseling; modest programs of counseling may be more cost effective in a stepped treatment strategy.

Can price get the monkey off our back? A meta-analysis of illicit drug demand.

Because of the increased availability of price data over the past 15 years, several studies have estimated the demand for illicit drugs, providing 462 estimates of the price elasticity. Results from estimating several meta-regressions reveal that these price elasticity estimates are influenced by a number of study characteristics. For instance, the price elasticity differs across drugs, with its absolute value being smallest for marijuana, compared with cocaine and heroin. Furthermore, price elasticity estimates are sensitive to whether demand is modeled in the short-run or the long-run, measures of quantity and price, whether or not alcohol and other illicit drugs are included in the specification of demand, and the location of demand. However, a number of other factors, including the functional form of demand, several specification issues, the type of data and method used to estimate demand, and the quality of the publication outlet, have less influence on the price elasticity.

A cost-benefit/cost-effectiveness analysis of an unsanctioned supervised smoking facility in the Downtown Eastside of Vancouver, Canada.

BACKGROUND: Smoking crack involves the risk of transmitting diseases such as HIV and hepatitis C (HCV). The current study determines whether the formerly unsanctioned supervised smoking facility (SSF)-operated by the grassroot organization, Vancouver Area Network of Drug Users (VANDU) for the last few years-costs less than the costs incurred for health-care services as a direct consequence of not having such a program in Vancouver, Canada. METHODS: The data pertaining to the attendance at the SSF was gathered in 2012-2013 by VANDU. By relying on this data, a mathematical model was employed to estimate the number of HCV infections prevented by the former facility in Vancouver's Downtown Eastside (DTES). RESULTS: The DTES SSF's benefit-cost ratio was conservatively estimated at 12.1:1 due to its low operating cost. The study used 70% and 90% initial pipe-sharing rates for sensitivity analysis. At 80% sharing rate, the marginal HCV cases prevented were determined to be 55 cases. Moreover, at 80% sharing rate, the marginal cost-effectiveness ratio ranges from $1,705 to $97,203. The results from both the baseline and sensitivity analysis demonstrated that the establishment of the SSF by VANDU on average had annually saved CAD$1.8 million dollars in taxpayer's money. CONCLUSIONS: Funding SSFs in Vancouver is an efficient and effective use of financial resources in the public health domain; therefore, Vancouver Coastal Health should actively participate in their establishment in order to reduce HCV and other blood-borne infections such as HIV within the non-injecting drug users.

Health care among street-involved women: the perpetuation of health inequity.

I present the findings from a study that explored the experiences and decision making of street-involved women navigating the health care system. Data were drawn from a larger qualitative study situated in a western Canadian inner-city neighborhood that examined the health-management strategies of street-involved women with a history of crack cocaine use. Data were collected over a 17-month period and included ethnographic methods of participant observation, group interviews (n = 57), and in-depth interviews (n = 10). Inductive thematic analysis derived two major themes: power and punishment, and organization and delivery of care. The themes illustrate how women's experiences and decision making were located within a nexus of power relations that operated across women's shared social location as downtown eastsiders. Implications of the findings are discussed in relation to supporting women's efforts and improving health outcomes.

Substitution and complementarity in the face of alcohol-specific policy interventions.

AIM: Policy responses to the growing burden of alcohol-related disease fail to consider the interrelated nature of substance misuse and the potential for complex interactions in response to alcohol-specific interventions. This paper considers possible aggregate level responses to the alcohol policy and whether alcohol policy can be expected to reduce overall harm. METHODS: A review and discussion of the relevant literature was conducted. RESULTS: Evidence indicates that those at greatest risk consume stronger alcoholic beverages more frequently, that they are likely to complement their consumption with a range of intoxicants and that they are more likely to substitute alcohol with other substances. CONCLUSIONS: Policies aimed at reducing alcohol consumption can be successful. However, evidence suggests a significant minority of consumers are likely to substitute or complement consumption with a range of intoxicants suggesting that policy is unlikely to reduce all-cause mortality and morbidity. Further research into the nature of substitution and complementarity is required.

Tolerance and sensitization to the effects of cocaine use in humans: a retrospective study of long-term cocaine users in Philadelphia.

In the effort to develop medications to combat addiction, researchers have developed models that attempt to describe the neurobiological process of cocaine dependence. It has not, however, yet been determined which of these models, if any, best fits the behaviors and experiences of patients. This project retrospectively evaluated changes in patients' experiences with cocaine over time in order to clarify the model that best fits clinical observations. In 2005 and 2007, 100 treatment-seeking, long-term cocaine users were recruited from an urban university-based treatment center in Philadelphia, PA, United States. Each participant was administered the "Cocaine History Questionnaire" which asked them to describe the initiation and escalation of their cocaine usage, changing reward perceptions, and effects of intoxication at certain points in their drug use careers. This data was then analyzed using repeated measures, examining the within subject differences in reported information over the time points. We found evidence that while the amount of drug used increases, self-reported euphoria decreases while negative symptoms associated with cocaine use also increase. The data provide preliminary evidence for the hedonic dysregulation model of addiction. Limitations and implications of the study are discussed in the conclusion.

Toward a global view of alcohol, tobacco, cannabis, and cocaine use: findings from the WHO World Mental Health Surveys.

BACKGROUND: Alcohol, tobacco, and illegal drug use cause considerable morbidity and mortality, but good cross-national epidemiological data are limited. This paper describes such data from the first 17 countries participating in the World Health Organization's (WHO's) World Mental Health (WMH) Survey Initiative. METHODS AND FINDINGS: Household surveys with a combined sample size of 85,052 were carried out in the Americas (Colombia, Mexico, United States), Europe (Belgium, France, Germany, Italy, Netherlands, Spain, Ukraine), Middle East and Africa (Israel, Lebanon, Nigeria, South Africa), Asia (Japan, People's Republic of China), and Oceania (New Zealand). The WHO Composite International Diagnostic Interview (CIDI) was used to assess the prevalence and correlates of a wide variety of mental and substance disorders. This paper focuses on lifetime use and age of initiation of tobacco, alcohol, cannabis, and cocaine. Alcohol had been used by most in the Americas, Europe, Japan, and New Zealand, with smaller proportions in the Middle East, Africa, and China. Cannabis use in the US and New Zealand (both 42%) was far higher than in any other country. The US was also an outlier in cocaine use (16%). Males were more likely than females to have used drugs; and a sex-cohort interaction was observed, whereby not only were younger cohorts more likely to use all drugs, but the male-female gap was closing in more recent cohorts. The period of risk for drug initiation also appears to be lengthening longer into adulthood among more recent cohorts. Associations with sociodemographic variables were consistent across countries, as were the curves of incidence of lifetime use. CONCLUSIONS: Globally, drug use is not distributed evenly and is not simply related to drug policy, since countries with stringent user-level illegal drug policies did not have lower levels of use than countries with liberal ones. Sex differences were consistently documented, but are decreasing in more recent cohorts, who also have higher levels of illegal drug use and extensions in the period of risk for initiation.

The effects of perceived quality on the behavioural economics of alcohol, amphetamine, cannabis, cocaine, and ecstasy purchases.

Previous research has indicated that non-dependent polydrug users are willing to pay more money to buy good quality drugs as their income increased. This study sought to examine whether altering the perceived quality of controlled drugs would affect drug purchases if the monetary price remained fixed. A random sample of 80 polydrug users were recruited. All participants were administered an anonymous questionnaire consisting of the Drug Abuse Screening Test for Adolescents (DAST-A), the Severity of Dependence Scale for cannabis (SDS), the Alcohol Use Disorders Identification Test (AUDIT), the Hospital Anxiety and Depression Scale (HADS), and questions about their drug use. Participants then completed a simulation of controlled drug purchases where the price of alcohol, amphetamine, cannabis, cocaine, and ecstasy remained the same but their perceived quality changed (i.e. unit price increased as the perceived quality decreased). The demand for alcohol was quality inelastic and alcohol quality had no effects on the purchase of any other controlled drug. Demand for cannabis was quality elastic and alcohol substituted for cannabis as its unit price increased. Demand for cocaine was quality elastic and alcohol, cannabis, and ecstasy substituted for cocaine as its unit price increased. Demand for ecstasy was quality elastic and alcohol and cocaine both substituted for ecstasy as its unit price increased. These results suggest that perceived quality influences the demand for controlled drugs and that monitoring the perceived quality of controlled drugs may provide a warning of potential public health problems in the near future.

Subjective responses and cardiovascular effects of self-administered cocaine in cocaine-abusing men and women.

This study aimed to examine sex differences in cocaine self-administration and cocaine-induced subjective and cardiovascular measures. The research was based on secondary analysis of data collected in our human laboratory in which subjects self-administered cocaine infusions (8, 16 and 32 mg/70 kg) over a 2-hour period under a fixed ratio 1, 5 minute time out schedule in three test sessions. Subjects were 10 women and 21 men with a history of either cocaine abuse or dependence who were not currently seeking treatment. Women and men self-administered similar amounts of cocaine. None of the subjective effects measures showed a significant main effect of sex during the cocaine self-administration session. Significant interactions were observed for subjective ratings of 'high' (sex x time) and 'stimulated' (sex x time x dose), with women reporting lower ratings over time/doses than men. Relative to men, cocaine produced dose- and time-dependent increases in feelings of hunger (i.e., reduced appetite suppression) in women. Systolic and diastolic blood pressures showed different patterns of change in men and women, with women showing less robust cocaine-induced increases than men. Taken together, these findings suggest that women and men may differ in their subjective and cardiovascular responses to self-administered cocaine. Further research that prospectively controls for hormonal influences upon these measures is needed.

Financing a voucher program for cocaine abusers through community donations in Spain.

This study analyzed the viability of financing a voucher program for cocaine addicts in Spain through public and private donations. Of the 136 companies contacted, 52 (38%) provided donations. The difference between the benefits (15,670 Euro/ $20,371) and the costs (3734 Euro/ $4854) was 11,936 Euro/ $15,517. The type of reinforcer a company can offer, the size of the company, and the time elapsed before responding may be determining variables in a company's decision whether to collaborate.

Behavioral economic analysis of the effects of N-substituted benztropine analogs on cocaine self-administration in rats.

RATIONALE AND OBJECTIVES: Benztropine (BZT) analogs and other atypical dopamine uptake inhibitors selectively decrease cocaine self-administration at doses that do not affect responding maintained by other reinforcers. Those effects were further characterized in the current study using a behavioral economic assessment of how response requirement (price) affects reinforcers obtained (consumption) in rats. METHODS: Two groups of rats were trained to press levers with food (45-mg pellet) or cocaine (0.32 mg/kg/injection) reinforcement under fixed-ratio (FR) 5-response schedules. In selected sessions, the FR requirement was increased (5-80) during successive 20-min components to determine demand curves, which plot consumption against price. An exponential function was fitted to the data to derive the consumption at zero price (Q 0) and the rate of decrease in consumption (essential value, EV) with increased price. The BZT analogs, AHN1-055, AHN2-005, JHW007 (3.2-10 or 17.8 mg/kg, each), vehicle, or comparison drugs (methylphenidate, ketamine), were administered i.p. before selected demand-curve determinations. RESULTS: Consumption of cocaine or food decreased with increased FR requirement. Each drug shifted the demand curve rightward at the lowest doses and leftward/downward at higher doses. The effects on EV and Q 0 were greater for cocaine than for food-reinforced responding. Additionally, the effects of the BZT analogs on EV and Q 0 were greater than those obtained with a standard dopamine transport inhibitor, methylphenidate, and the NMDA antagonist, ketamine (1.0-10.0 mg/kg, each). With these latter drugs, the demand-curve parameters were affected similarly with cocaine and food-maintained responding. CONCLUSIONS: The current findings, obtained using a behavioral economic assessment, suggest that BZT analogs selectively decrease the reinforcing effectiveness of cocaine.

Effects of varying the monetary value of voucher-based incentives on abstinence achieved during and following treatment among cocaine-dependent outpatients.

AIMS: This study examined whether increasing the amount of abstinence achieved during outpatient treatment for cocaine dependence is an effective method for increasing longer-term cocaine abstinence. DESIGN: A two-condition, parallel groups, randomized controlled trial was conducted. SETTING: The trial was conducted in a university-based research clinic. PARTICIPANTS: A total of 100 cocaine-dependent outpatients participated in the trial. INTERVENTION: Participants were assigned randomly to receive treatment based on the community reinforcement approach (CRA) plus voucher-based incentives set at a relatively high monetary value (maximal value = $1995/12 weeks) or CRA with vouchers set at a relatively low monetary value (maximal value = $499/12 weeks). Vouchers were earned contingent on cocaine-negative urinalysis results during the initial 12 weeks of the 24-week outpatient treatment. MEASUREMENTS: Outcomes were evaluated using urine-toxicology testing, questionnaires and other self-report instruments. FINDINGS: Increasing voucher value increased the duration of continuous cocaine abstinence achieved during the 24-week treatment period. Point-prevalence cocaine abstinence assessed every 3 months throughout an 18-month follow-up period was greater in the high- than low-value voucher conditions. The duration of abstinence achieved during treatment predicted abstinence during follow-up, although that relationship weakened over time. CONCLUSIONS: Increasing the value of abstinence-contingent incentives during the initial weeks of treatment appears to represent an effective method for increasing during-treatment and longer-term cocaine abstinence, but the positive association of during-treatment abstinence with longer-term outcome dissipates with time.

What do we get for our money? Cost-effectiveness of adding contingency management.

AIMS: To assess the relative cost-effectiveness of lower versus higher cost prize-based contingency management (CM) treatments for cocaine abuse. DESIGN: Cost-effectiveness analyses based on resource utilization, unit costs and outcomes from a previous CM efficacy trial. SETTING: Two community-based treatment centers. PARTICIPANTS: Patients (n = 120) enrolled in out-patient treatment for cocaine abuse. INTERVENTION: Random assignment to one of three 12-week treatment conditions: standard treatment (STD) alone or two variants of STD combined with prize based CM. In CM, drawing for prizes was available to those submitting drug-free urine samples and completing goal-related activities. There were two levels of pay-out (referred to as $80 versus $240) based on the potential value of prizes won. MEASUREMENTS: Costs per participant associated with counseling utilization, urine and breathalyzer testing, and operation of the prize-drawing procedure were derived from a survey conducted at 16 clinics that had participated in CM studies. The three measures of effectiveness were: (1) longest duration of consecutive abstinence; (2) percentage completing treatment; and (3) percentage of samples drug-free. FINDINGS: The higher magnitude CM produced outcomes at a lower per unit cost than did the lower magnitude prize CM treatment. This was the case for all three outcome measures examined and held across various assumptions in the sensitivity analysis. CONCLUSIONS: Cost-effectiveness analyses can inform policy decisions regarding selection of one treatment model over another. Decisions on adoption of new evidence-based treatments would be aided by more information on society's willingness to pay for incremental gains in effectiveness.

Subjective sensitivity to monetary gradients is associated with frontolimbic activation to reward in cocaine abusers.

Drug addiction is characterized by marked disruptions in the ability to process reward. Here we evaluated in cocaine addicted and healthy control participants the subjective sensitivity to reward gradients and its association with neural responses to sustained reward. A self-report questionnaire was used to assess the former. A functional magnetic resonance imaging task that utilized monetary reward as feedback in a blocked design was used to assess the latter. Results revealed that whereas control subjects valued high money more than low money, over half of the cocaine addicted subjects valued all monetary amounts equally. This compromised subjective sensitivity to gradients in reward value was significantly correlated with higher activations to money in the lateral orbitofrontal cortex/inferior frontal gyrus (BA 47) and amygdala, and lower activations in the middle frontal gyrus (BA 6), which together explained 85% of the variability on this rating scale in the cocaine abusers only. These results provide for the first time evidence of restricted subjective sensitivity to gradients of reward in cocaine addiction and of the involvement of frontolimbic brain regions (including the orbitofrontal cortex) in this deficit.

Identification and quantification of change in Australian illicit drug markets.

BACKGROUND: In early 2001 Australia experienced a sudden reduction in the availability of heroin which had widespread effects on illicit drug markets across the country. The consequences of this event, commonly referred to as the Australian 'heroin shortage', have been extensively studied and there has been considerable debate as to the causes of the shortage and its implications for drug policy. This paper aims to investigate the presence of these epidemic patterns, to quantify the scale over which they occur and to estimate the relative importance of the 'heroin shortage' and any epidemic patterns in the drug markets. METHOD: Key indicator data series from the New South Wales illicit drug market were analysed using the statistical methods Principal Component Analysis and SiZer. RESULTS: The 'heroin shortage' represents the single most important source of variation in this illicit drug market. Furthermore the size of the effect of the heroin shortage is more than three times that evidenced by long-term 'epidemic' patterns. CONCLUSION: The 'heroin shortage' was unlikely to have been a simple correction at the end of a long period of reduced heroin availability, and represents a separate non-random shock which strongly affected the markets.

Delay discounting in currently using and currently abstinent cocaine-dependent outpatients and non-drug-using matched controls.

Higher rates of delay discounting have been consistently noted in substance abusers compared to non-drug-using matched controls. Additional data from some studies comparing discounting rates in current versus former substance abusers suggest that discounting rates may be adaptable and that drug abstinence may be associated with reductions in discounting. The primary purpose of the present study was to determine whether a period of cocaine abstinence (at least 30 days) resulted in altered discounting rates of money in a population of primary cocaine-dependent patients compared to current cocaine users and non-drug-using matched controls. Results suggest that there was no difference in discounting between currently abstinent and currently using cocaine-dependent outpatients. When these two groups were combined, cocaine-dependent patients showed higher discounting rates than non-drug-using matched controls. These data replicate previous work in cocaine-dependent and other substance abusers compared to non-drug-using controls and suggest that a longer period of abstinence may be required to modify discounting in this population.

[Cocaine abuse in Vienna and European cities--a multi-center study]. / Kokainmissbrauch in Wien und in europäischen Metropolen--eine multizentrische Studie.

INTRODUCTION: As cocaine consumption seems to have increased over the last decades, the EU has funded this multi-center, cross-sectional survey to investigate cocaine consumption in three different target groups. The study was conducted by the Addiction Clinic, Department of Psychiatry, Medical University Vienna and other nine European cities. METHODS: Data were collected by structured face-to-face interviews. The sample was composed of 211 cocaine abusers out of three target groups: (1) treatment group undergoing opioid maintenance therapy, (2) marginalized scene group and (3) integrated party group. Sociodemographic data such as age, education, employment, monthly expenses on cocaine/crack, data on consumption patterns, physical and mental health and personal needs regarding cocaine consumption were evaluated. Urine toxicology results for cocaine in the treatment group completed the analysis. RESULTS: The marginalized scene group was the oldest with a mean age of 29.35 years, with the highest unemployment rate (mean 25.11 days) and the longest duration of cocaine consumption (mean 5.80 years). They had the highest cocaine consumption pattern with a mean of 22.32 days within the last month. On average 1969 Euros/months was spent for their addiction. The treatment group had the lowest school education with a mean of 10.36 years, but showed a sufficient insight in their cocaine problem. However, the party group (with the lowest mean age, 25.64 years) highly underestimated their drug problem, the mean amount of money they spent for their addiction was 588.99 Euro/months. Structured urine toxicology between 1996 and 2002 in patients undergoing opioid maintenance therapy ("treatment group") revealed a significant increase of concomitant cocaine consumption (1996: 33.1%; 2002: 40.2%; p = 0.044). DISCUSSION: The European trend of increased cocaine use could also be observed in Vienna. One of the greatest barriers for establishing adequate treatment settings for this target group is the difficulty to reach this population. In addition, multiple substance abuse seems to be one of the predominating patterns of cocaine consumption and this aspect should be integrated within treatment (in the treatment and scene groups additional heroin and benzodiapzepines abuse is observed, in the party group intensive alcohol consumption). The Viennese results are in line with those of the other European cities; however, it could not be confirmed that consumption of crack cocaine and binge play a similarly significant role as in cities such as Hamburg or London.

Comparing exponential and exponentiated models of drug demand in cocaine users.

Drug purchase tasks provide rapid and efficient measurement of drug demand. Zero values (i.e., prices with zero consumption) present a quantitative challenge when using exponential demand models that exponentiated models may resolve. We aimed to replicate and advance the utility of using an exponentiated model by demonstrating construct validity (i.e., association with real-world drug use) and generalizability across drug commodities. Participants (N = 40 cocaine-using adults) completed Cocaine, Alcohol, and Cigarette Purchase Tasks evaluating hypothetical consumption across changes in price. Exponentiated and exponential models were fit to these data using different treatments of zero consumption values, including retaining zeros or replacing them with 0.1, 0.01, or 0.001. Excellent model fits were observed with the exponentiated model. Means and precision fluctuated with different replacement values when using the exponential model but were consistent for the exponentiated model. The exponentiated model provided the strongest correlation between derived demand intensity (Q0) and self-reported free consumption in all instances (Cocaine r = .88; Alcohol r = .97; Cigarette r = .91). Cocaine demand elasticity was positively correlated with alcohol and cigarette elasticity. Exponentiated parameters were associated with real-world drug use (e.g., weekly cocaine use) whereas these correlations were less consistent for exponential parameters. Our findings show that selection of zero replacement values affects demand parameters and their association with drug-use outcomes when using the exponential model but not the exponentiated model. This work supports the adoption of the exponentiated demand model by replicating improved fit and consistency and demonstrating construct validity and generalizability. (PsycINFO Database Record