To the Editor: In the literature on Axis I comorbidity in borderline personality disorder (BPD), males with BPD invariably evidence significantly higher rates of substance use disorders than females.1–5 In a previous study, we found that the self-reported abuse of prescription medications was associated with BPD, according to 2 self-report measures for this Axis II disorder.6 However, we did not undertake an analysis of gender. We wondered whether males would evidence higher rates of prescription substance abuse, echoing the current literature. Method. Participants were men and women, ages 18 to 65 years, who were being seen at an outpatient internal medicine clinic for nonemergent medical care. Exclusion criteria were medical (eg, dementia, pain), intellectual (eg, mental retardation), or psychiatric disorders (eg, psychotic) that would preclude the completion of a research booklet. A total of 492 people were invited to participate; 419 agreed, for a response rate of 85.2%. Of these, 130 were male and 287 were female (2 failed to indicate sex). Respondents ranged in age from 18 to 65 years (mean = 49.48 years, SD = 15.26 years). Most were white/Caucasian (358; 85.4%); 35 were African American, 11 were classified as “other,” 8 were Native American, 4 were Asian, 2 were Hispanic, and 1 failed to indicate race/ethnicity. With regard to education, most (92.1%) had at least graduated high school, with 159 (37.9%) having attended some college and 110 (26.3%) having earned at least a 4-year college degree. One of the authors (C. L.) approached incoming patients in the lobby of the outpatient facility, informally assessed exclusion criteria, and invited candidates to participate. Participants completed a 4-page research booklet and placed completed research booklets into sealed envelopes and then into a collection box in the lobby. The initial section of the research booklet explored demographic information. The next section contained the Self-Harm Inventory (SHI),7 a 22-item assessment that explores lifetime history of self-harm behaviors. One item on the SHI asks, “Have you ever intentionally, or on purpose, abused prescription medication?” The final section of the research booklet contained the borderline personality scale of the Personality Diagnostic Questionnaire-4 (PDQ-4).8 Data were collected during April 2009. This project was approved by the institutional review boards of the affiliated community hospital as well as the university. Survey completion was assumed to be implied consent. Results. In this sample, 118 men and 272 women completed both the SHI item relating to the abuse of prescription medications and the PDQ-4. Eleven men and 22 women endorsed the abuse of prescription medications. As for associations with BPD, using a cut-off score of 5 on the PDQ-4, 5 of the preceding men scored in the range suggestive of BPD, resulting in 27.8% of male participants with BPD endorsing the abuse of prescription medications. Likewise, 11 of the women who endorsed the abuse of prescription medications scored in the PDQ-4 range suggestive of BPD, resulting in 26.1% of female participants with BPD endorsing the abuse of prescription medications—nearly identical proportions. According to these data, in internal medicine outpatients with BPD, there are no discernible gender differences with regard to the abuse of prescription medications. Note that these data are in contrast with the existing literature on gender differences in BPD and comorbid substance abuse. This finding may be explained by the possibility that women may excuse substance-abuse behavior if the substance is a legitimate prescription, rather than an illicit street substance. Regardless of explanation, this finding indicates that clinicians need to be equally alert to the abuse of prescription medications in both males and females with BPD—a finding that is unique to the current literature. This study has a number of potential limitations, including the self-report nature of the data and the associated inherent difficulties with this type of methodology; the small total number of individuals who reported the abuse of prescription medications, which potentially compromises statistical interpretation; and the lack of clarification regarding either the nature of the abuse or type of abused prescription substance. However, this is the first study, to our knowledge, to examine gender patterns in self-reported prescription abuse, and the findings are novel in that they are contrary to the established findings of a gender difference in patients with BPD with regard to other types of substance abuse.