Males vs. Females: Recovering from Cocaine Addictions

Elena Malloy | elena.malloy@yale.edu April 16, 2014

Is it better to be both easily addicted and easily cured, or to be resistant to both addiction and treatment? Most people will never be able to decide either way. As Yale scientists have recently discovered, sex is an important determinant of how addicts respond to treatment. Specifically, in the context of cocaine addition, females responded positively to the drug guanfacine while in males, this treatment had no effect.

 Guanfacine hydrochloride, the drug used to treat cocaine addictions. Image courtesy of drugs.com

Guanfacine hydrochloride, the drug used to treat cocaine addictions. Image courtesy of drugs.com

Gender differences in response to cocaine treatment have been a growing topic of interest. The first paper on this topic, published in 1993, focused on the disparity in rehabilitation between female and male cocaine users. Using pharmacotherapies, the scientists found that females had more extreme drug problems at the start of the experiment, yet experienced faster rehabilitation and more complete recovery.

Recently, a study done at Yale University has found similar results. Led by Dr. Rajita Sinha, Foundations’ Fund Professor of Psychiatry, along with Dr. Peter Morgan and Dr. Helen Fox, the team tested two substances for effectiveness in reducing cocaine dependency and negative side effects. Participants in the study were given a placebo or one of the two substances, alpha 2 adrenergic agonist or guanfacine HCl. After four weeks of administered doses, the researchers measured the patients’ craving, negative emotion, and anxiety.

From this study, the team concluded that females and males respond differently in cocaine addiction treatment. Specifically, for females, guanfacine reduced cocaine craving, negative emotion, and anxiety. This is in sharp contrast to the cocaine cravings for those on the placebo. Females exhibited higher cravings than males when only on the placebo. However, males did not have success while on guanfacine. In both sexes guanfacine reduced stress and blood pressure. These results clearly demonstrate the differences in drug responses based on gender.

Researchers also measured alcohol and nicotine cravings and found similar results in alcohol addiction, but not in nicotine addiction. Females, again, experienced lower alcohol cravings after being given guanfacine as opposed to males. The males did, however, have lower alcohol cravings on the placebo than females on the placebo. The nicotine study revealed that both males and females had lower cravings after being given guanfacine.

Cocaine in powder form. Image courtesy of matrixdiagnostics.co.uk

Cocaine in powder form. Image courtesy of matrixdiagnostics.co.uk

Despite these seemingly conclusive results, the experiment does not prove definitively that women are more easily treated for cocaine addiction. As Dr. Peter Morgan, an author of the paper, pointed out, “the women in the study used more cocaine and used cocaine more frequently than the men in the study.” Additionally, the scientists are not sure whether this is a general trend in all addictions, or something specific to cocaine. In order to investigate this question, the researchers are currently performing an alcohol addiction study “looking at the disparity in male and female treatment, primarily the longer treatment outcome,” according to Morgan.

Treatment is not the only gendered difference scientists have found in cocaine usage. For example, researchers at the University of Michigan found that not only do men and women have different responses to cocaine, but women also have varied responses according to their menstrual cycle. Duke University scientists have also found that males and females responded differently to gonadectomy and gonadal hormones in response to cocaine.

Based on these studies, it is clear that there is a disparity in female and male responses to cocaine. Though females are more susceptible to addiction, they seem to also be more responsive to treatment. This is not a characteristic of cocaine addiction alone, as the Yale team showed that there are similar results seen in alcohol addiction. As more research is done on this topic, perhaps physicians will one day start prescribing gender-specific treatments for a variety of scenarios.