Background and Objectives <p>The rising prescription rates and opioid-related harms in France highlight the need for local data. Evaluating this association may help identify vulnerable subgroups and guide safer prescribing practices. This study aimed to assess the association between opioid analgesic dispensation and the risk of suicide attempt in the French population. Secondary objectives included evaluation of a dose–response relationship and examination of the potential additive effects of co-prescriptions with benzodiazepines or gabapentinoids.</p> Methods <p>We conducted a nationwide, population-based case-crossover study using data from the French National Health Insurance Database (Système National des Données de Santé, SNDS), covering 98.8% of the French population. Adults aged 18 years or older who were hospitalized for a first suicide attempt between 1 January 2013 and 31 December 2020, and who had received at least one opioid analgesic dispensation in the preceding year (excluding buprenorphine and methadone) were included. Opioid analgesic exposure during the 84 days before the attempt was compared with three earlier 84-day control periods.</p> Results <p>Among 158,400 patients (mean age 47.0 years; 64.0% women), opioid analgesic dispensation was associated with a higher risk of suicide attempt (odds ratio [OR] = 1.26; 95% confidence interval 1.25–1.28). The risk was greater for strong opioid analgesics (OR = 1.73) and higher morphine-equivalent doses. Co-prescription with benzodiazepines or gabapentinoids further increased risk.</p> Conclusions <p>Opioid analgesic use, especially at higher doses or in combination with benzodiazepines or gabapentinoids, was associated with an increased risk of suicide attempt. Clinical vigilance is warranted when prescribing these medications.</p> Trial Registration <p>NCT04211077, registered 3 January 2020 (retrospectively registered).</p>