From opioids to methamphetamine: an eleven‑year analysis of changing drug treatment admissions in Türkiye, 2013–2023

Substance use disorders pose a major public health challenge globally, with marked shifts from plant-based to synthetic drugs over the past decade. Türkiye, situated on the Balkan Route, has become both a destination and a production hub for synthetic substances. This study analyzes eleven-year trends in drug treatment admissions, demographic characteristics, drug-related deaths, and infectious disease burden among people who inject drugs (PWID) to inform clinical practice and health policy. We conducted a retrospective epidemiological analysis of data from Turkish National Drug Reports (2013–2023). Joinpoint regression was used to identify significant changes in trends. Descriptive statistics, Z-tests for proportions, and Pearson correlations were applied. Sensitivity analyses excluded 2016 and the pandemic years (2020–2021) to test robustness. Total treatment admissions increased by 60% (from 226,471 in 2013 to 362,561 in 2023). Joinpoint analysis demonstrated a continuous, statistically significant upward trend throughout the decade (APC = 4.12%, 95% CI: 1.03% to 7.41%, p = 0.011). The share of opioid-related admissions dropped from 76.3% (2013) to 4.2% (2023), while methamphetamine admissions surged from 0.25% (2014) to 37.1% (2023). Female admissions increased from 5.6% to 9.7% ( p < 0.05), with a significant upward trend after 2017 (APC = 12.34%, p = 0.013). Mean age at treatment rose from 24.3 to 27.6 years ( p < 0.05). Drug-related deaths peaked in 2017 (941), then declined by 73.9% by 2021, but increased slightly in 2023. HIV seroprevalence among PWID increased 6.7-fold (from < 0.21% to 1.2%, p < 0.05), while HCV remained high (41.7% in 2023). A strong correlation was found between methamphetamine seizures and treatment admissions ( r = 0.812, p = 0.026). Türkiye has undergone a rapid transition from opioid-dominant to methamphetamine-dominant substance use patterns, accompanied by demographic shifts (aging population, more women) and escalating HIV risk among PWID. While reductions in drug-related deaths and adolescent admissions indicate some policy successes, the methamphetamine epidemic and emerging infectious disease syndemic require urgent adaptation of treatment systems, expansion of harm reduction services, and gender-responsive care. These findings carry early-warning value for other Balkan countries facing similar synthetic drug pressures. Not applicable.