Real-world antidepressant prescribing patterns in outpatient care: a cross-sectional analysis

Depression is a major global health concern, with rising prevalence across all populations and regions. Antidepressants are a cornerstone of treatment, yet their use varies widely depending on drug class, patient demographics, and prescriber characteristics. Understanding real-world prescribing patterns is essential for optimizing care and informing policy. In Iran, despite widespread use of antidepressants, large-scale, data-driven studies examining these trends remain limited. This study aims to analyze outpatient antidepressant prescription patterns in Tabriz, Iran, from March 2022 to March 2023. Data were obtained from two major national health insurance providers: the Social Security Organization (SSO) and the Iran Health Insurance Organization (IHIO). A total of 19 antidepressant medications were selected, and prescriptions were examined in relation to drug type, patient age and sex, and physician specialty. During the study period, 570,599 antidepressant prescriptions were issued to 291,089 unique patients, corresponding to an overall prescribing rate of approximately 191.6 per 1000 insured persons and an average of 1.96 prescriptions per patient. The majority of patients were female (67.5%) with a mean age of 47.5 years. Most prescriptions were for adults aged 19–59 (70%), followed by older adults (24.8%). Selective serotonin reuptake inhibitors (SSRIs) were the most commonly prescribed class (58.8%), particularly sertraline and fluoxetine. Tricyclic antidepressants (TCAs) accounted for 27.7%, with nortriptyline as the leading agent; notably, a substantial proportion of TCA prescriptions were dispensed at the 10-mg unit strength, below the WHO Defined Daily Dose for these agents; however, unit strength alone could not establish actual daily dose or treatment indication. Psychiatrists issued the highest proportion of prescriptions (28.9%), followed by general practitioners and other specialties (22.1%) and internists (20.7%). Psychiatrists also showed the highest prescribing intensity, with an average of 2.86 prescriptions per patient compared with an overall average of 1.96. Prescription coverage was primarily through the SSO (77.9%). Drug class was significantly associated with both sex and physician specialty, although the corresponding effect sizes were small (Cramér’s V = 0.048 and 0.129, respectively). Surgeons prescribed proportionally more TCAs, whereas psychiatrists prescribed relatively more SNRIs, NDRIs, SARIs, and TeCAs. SSRIs have emerged as the most frequently prescribed class of antidepressants, which aligns with global preferences for these medications. Nonetheless, tricyclic antidepressants, particularly nortriptyline, continue to be commonly utilized, probably because of their affordability, the comfort level of physicians with these medications, and their diverse treatment use cases within limited resource settings. The findings underscore the necessity for enhanced prescribing guidelines, more comprehensive education for physicians, improved referral processes to psychiatric specialists, and focused monitoring of high-use demographics, particularly women and adults in Iran.