Social justice concerns-the exploration of women’s economic, political, and social vulnerability-are displaced by the emphasis on biological and endocrinological activity. Gender-specific drug research investigates women’s greater “biological vulnerability” to addiction by studying interactions between sex hormones and neurotransmitters.1 Biological reductionism prevents us from attending to questions of value, judgment, and bias in gender-specific research and treatment, and obscures other social formations-race, ethnicity, sexuality, and class-that intersect with gender in both the experience of addiction and scientific research. Gender difference is conflated with biological sexual difference in recent genderspecific studies on the pharmacological effects of illicit drugs.