Cocaine intoxication

Cocaine vaccine dAd5GNE protects against moderate daily and high-dose "binge" cocaine use

The cocaine vaccine dAd5GNE is comprised of a disrupted serotype 5 adenovirus gene therapy vector covalently conjugated to the cocaine analog GNE. The vaccine evokes a high titer of circulating anti-cocaine antibodies that prevent cocaine from reaching its cognate receptors in the central nervous system. Prior studies have demonstrated the efficacy of dAd5GNE in models of occasional, moderate cocaine use. However, previous studies have not sufficiently evaluated the efficacy of dAd5GNE in models of the repetitive and high-dose "binge" use patterns common in human addicts. In the present study, we evaluated the capacity of dAd5GNE vaccination to protect against "binge" cocaine use and circumstances where vaccinated addicts attempt to override the vaccine. We modeled repetitive daily cocaine use in vaccinated Balb/c mice and African green monkeys, and evaluated high-dose "binge" scenarios in Balb/c mice. In each model of daily use the dAd5GNE vaccine prevented cocaine from reaching the central nervous system. In the high-dose "binge" model, vaccination decreased cocaine-induced hyperactivity and reduced the number of cocaine-induced seizures. Based on this data and our prior data in rodents and nonhuman primates, we have initiated a clinical trial evaluating the dAd5GNE anti-cocaine vaccine as a potential therapy for cocaine addicts who wish to stop cocaine use. If dAd5GNE vaccination is safe and produces high anti-cocaine antibody titers in the clinic, we hypothesize that the vaccine will restrict the access of cocaine to the central nervous system and inhibit cocaine-induced "highs" even in the context of moderate daily and high-dose "binge" use that might otherwise cause a drug-induced overdose.

Is crack cocaine use associated with greater violence than powdered cocaine use? Results from a national sample

BACKGROUND

The question of whether crack cocaine use is associated with increased violence compared to powdered cocaine use has not been adequately explored in large nationally representative general population samples.

METHODS

This study used data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) to 1) determine the comparative prevalences of violent behaviors among crack cocaine users and powdered cocaine users, 2) examine these differences while controlling for sociodemographic variables, lifetime psychiatric, alcohol and drug use disorders (a majority of cocaine users use other substances), and levels of crack cocaine and powdered cocaine use.

RESULTS

The likelihood of violence associated with crack cocaine users was greater compared to powdered cocaine users at the bivariate level. However, these differences were almost uniformly statistically nonsignificant when demographic, mood and non-cocaine substance use disorders were controlled for.

CONCLUSIONS

The substantial attenuation of the association of crack cocaine use with violence after adjustment suggests that the sociodemographic characteristics, psychiatric variables, and non-cocaine substance use disorders that make some individuals more likely to use crack cocaine than powder cocaine are responsible for the increased prevalence of violence observed among crack users, rather than crack itself.

Emergency department observation for toxicologic exposures

Most toxicologic exposures resolve within 24 hours, yet catastrophic outcomes may occur if patients are directly discharged from the emergency department (ED). These cases are, perhaps, the ideal candidates for observation unit (OU) management. This article reviews the criteria for admission and discharge as well as clinical management strategies in the OU for the most common toxicologic exposures. Special attention is given to the multidisciplinary interactions among the ED physician, the medical toxicologist, the physiatrist, and the specialty laboratory.

The effect of morphine and naloxone on cocaine toxicity

The effect of morphine and naloxone on acute cocaine toxicity was studied. Male Sprague-Dawley rats were pretreated intraperitoneally (ip) with saline, morphine sulfate 25 mg/kg, or naloxone 1.0 mg/kg 15 minutes prior to challenge by cocaine. After pretreatment, each group was challenged with one of three doses of cocaine (35, 50, or 75 mg/kg ip). Each of the nine drug combinations was tested on at least 10 animals. Animals were observed for behavior, seizures, and death. The animals pretreated with saline and challenged with cocaine (35, 50, or 75 mg/kg) had seizure incidences of 0%, 40%, and 100%, respectively, after increasing doses. Pretreatment with morphine resulted in cocaine-induced seizures of 20%, 80% and 100%, respectively (p less than or equal to 0.05 with cocaine 35 and 50 mg/kg). Time to seizures in these groups did not differ significantly compared to the saline groups. Pretreatment with naloxone resulted in cocaine-induced seizures of 0%, 50%, and 60% (p less than or equal to 0.05 at the 75 mg/kg dose). The incidence of death was significantly increased by pretreatment with morphine in animals that received cocaine 50 or 75 mg/kg. The time to death was not significantly different compared to saline controls. The death rate in naloxone pretreated animals was not significantly different from the saline groups. In additional studies, high-dose naloxone pretreatment (10 mg/kg) also failed to provide protection from acute cocaine toxicity. In conclusion, cocaine toxicity is potentiated by morphine and does not appear to be altered by naloxone.

Lidocaine potentiation of cocaine toxicity

STUDY HYPOTHESIS

The toxic effects of cocaine are enhanced in the presence of lidocaine.

STUDY POPULATION

Male Sprague-Dawley rats weighing 200 to 300 g.

METHODS

Animals received intraperitoneal injections of cocaine (10, 20, 35, or 50 mg/kg), lidocaine (30 or 40 mg/kg), or a combination of all doses of cocaine given simultaneously with 30 or 40 mg/kg lidocaine. The incidence and time to seizure and death were recorded in these groups and compared by chi 2 and analysis of variance analyses, respectively.

RESULTS

At doses of 30 or 40 mg/kg, lidocaine does not induce seizures or death. The effect of simultaneous injection of both cocaine and lidocaine was to dramatically increase the incidence of both seizures and death over that of cocaine alone. The incidence of seizures in animals receiving 35 mg/kg cocaine alone was 10%; this increased to 50% and 80% with the addition of 30 and 40 mg/kg lidocaine, respectively (P less than or equal to .05; P less than or equal to .01). Death did not occur in animals receiving 35 mg/kg cocaine alone; the addition of 30 and 40 mg/kg lidocaine resulted in death in 30% and 60% of animals, respectively (P less than or equal to .01 each group). Similarly, in rats receiving 50 mg/kg cocaine, the incidence of death increased from 0% to 60% and 80% with 30 and 40 mg/kg lidocaine, respectively (P less than or equal to .01).

CONCLUSION

In the rat, overall toxicity of cocaine is significantly increased with simultaneous exposure to lidocaine.

Crack abuse. Do you known enough about it?

Crack use has increased dramatically because the drug is cheap, highly addictive, and easy to use. As a result, an increased frequency of cocaine-related medical problems has been noted. The effects of crack abuse on fetal outcome and neurobehavioral development are becoming more apparent. In addition, the role of crack use in furthering transmission of sexually transmitted diseases has been documented, and the implications for AIDS transmission have been speculated on. Crack use enhances social disorganization, particularly in poor urban areas, where increased child abuse, neglect, and prostitution are common. Ever present are the financial incentives to increase the number of crack users. Cocaine was once considered a drug for the elite, rich, and famous. Crack clearly has changed that notion.