Injection drug users (IDUs) may be denied purchase of sterile syringes even where purchase without a prescription is legal. This study examined barriers to over-the-counter (OTC) syringe purchase among IDUs in Tijuana, Mexico. A quantitative survey and subsequent focus groups were used to quantify barriers to purchase, identify their correlates and provide in-depth exploration of syringe purchase experiences. Of 627 IDUs, 81% purchased a syringe in the past 6 months and 16% were refused or overcharged. Factors independently associated with refusal/overcharging were homelessness, receptive syringe sharing, >5 uses per syringe, and number of lifetime abscesses. Few pharmacies sold syringes to IDUs, who adapted by limiting purchase attempts to pharmacies known to sell syringes consistently. Failed purchases occurred when drug withdrawal required purchase at unusual times or locations, often following release from jail. IDUs reported syringe sharing, syringe reuse, and searching through unsecured medical waste for syringes in response to failed purchase attempts. Interventions to expand OTC syringe sales to IDUs, particularly near detention facilities, will facilitate safer injection practices.

Abstract Background Sterile syringe access is a critical component of HIV prevention programs. Although retail pharmacies provide convenient outlets for syringe access, injection drug users (IDUs) may encounter barriers to syringe purchase even where purchase without a prescription is legal. We sought to obtain an objective measure of syringe access in Tijuana, Mexico, where IDUs report being denied or overcharged for syringes at pharmacies. Methods Trained "mystery shoppers" attempted to buy a 1 cc insulin syringe according to a predetermined script at all retail pharmacies in three Tijuana neighborhoods. The same pharmacies were surveyed by telephone regarding their syringe sales policies. Data on purchase attempts were analyzed using basic statistics to obtain an objective measure of syringe access and compared with data on stated sales policies to ascertain consistency. Results Only 46 (28.4%) of 162 syringe purchase attempts were successful. Leading reasons for unsuccessful attempts were being told that the pharmacy didn't sell syringes (35.3%), there were no syringes in stock (31.0%), or a prescription was required (20.7%). Of 136 pharmacies also surveyed by telephone, a majority (88.2%) reported selling syringes but only one-third (32.5%) had a successful mystery shopper purchase; the majority of unsuccessful purchases were attributed to being told the pharmacy didn't sell syringes. There was similar discordance regarding prescription policies: 74 pharmacies said in the telephone survey that they did not require a prescription for syringes, yet 10 of these pharmacies asked the mystery shopper for a prescription. Conclusions IDUs in Tijuana have limited access to syringes through retail pharmacies and policies and practices regarding syringe sales are inconsistent. Reasons for these restrictive and inconsistent practices must be identified and addressed to expand syringe access, reduce syringe sharing and prevent HIV transmission.

We analyzed data from a longitudinal cohort study of persons who inject drugs (PWID) in Tijuana, Mexico, to explore whether cigarette smoking increases the risk of interferon gamma release assay (IGRA) conversion. PWID were recruited using respondent driven sampling (RDS). QuantiFERON-TB Gold In-Tube (QFT) assay conversion was defined as interferon-gamma concentrations <0.35 IU/mL at baseline and ≥0.7 IU/mL at 18 months. We used multivariable Poisson regression adjusted for RDS weights to estimate risk ratios (RRs). Of 129 eligible participants, 125 (96.9%) smoked at least one cigarette during followup with a median of 11 cigarettes smoked daily, and 52 (40.3%) had QFT conversion. In bivariate analysis, QFT conversion was not associated with the number of cigarettes smoked daily (P = 0.716). Controlling for age, gender, education, and alcohol use, the RRs of QFT conversion for smoking 6-10, 11-15, and ≥16 cigarettes daily compared to smoking 0-5 cigarettes daily were 0.9 (95% confidence interval (CI), 0.5-1.6), 0.5 (95% CI, 0.3-1.2), and 0.7 (95% CI, 0.3-1.6), respectively. Although this study did not find an association between self-reported smoking intensity and QFT conversion, it was not powered sufficiently to negate such an association. Larger longitudinal studies are needed to fully explore this relationship.