Background: Antimicrobial resistance is a major global public health threat that compromises the effectiveness of antimicrobial agents and increases morbidity, mortality, and healthcare costs. Public knowledge, awareness, risk perception, and antibiotic-use behaviors are important determinants of antimicrobial misuse and resistance development.

Objective: This study aimed to assess knowledge, awareness, risk perception, and antibiotic-use practices related to antimicrobial resistance among adults living in Tehran, Iran, and to identify demographic and behavioral predictors of adequate knowledge.

Methods: A community-based cross-sectional study was conducted among 200 adults in Tehran, Iran. Participants were recruited from public places, pharmacies, outpatient clinics, universities, and community centers using a multistage convenience sampling approach. Data were collected using a structured questionnaire consisting of demographic characteristics, antibiotic-use behaviors, antimicrobial resistance knowledge, awareness and risk perception, and preventive practices. Knowledge scores were categorized as poor, moderate, and good. Descriptive statistics, chi-square tests, independent-samples t-tests, one-way ANOVA, Pearson correlation analysis, and multivariable logistic regression were used to analyze the data.

Results: Among 200 participants, 112 were female and 88 were male. The mean age was 36.7±11.9years. Overall, 83 participants, equal to 41.5%, had good knowledge of antimicrobial resistance, while 76, equal to 38.0%, had moderate knowledge and 41, equal to 20.5%, had poor knowledge. Although 72.5% of participants had heard of antibiotic resistance, only 46.0% correctly recognized that antibiotics are ineffective against viral infections. Self-medication with antibiotics during the previous year was reported by 37.0% of participants. Higher educational level, healthcare-related occupation, prior exposure to antimicrobial resistance information, and completion of prescribed antibiotic courses were positively associated with good knowledge. In contrast, antibiotic self-medication and expectation of antibiotics for cold or flu symptoms were negatively associated with good knowledge. In multivariable logistic regression, bachelor’s degree or higher education, healthcare-related occupation, and previous exposure to antimicrobial resistance information remained independent predictors of good knowledge.

Conclusion: Public knowledge of antimicrobial resistance among adults in Tehran was suboptimal, despite moderate awareness of the issue. Misconceptions regarding antibiotic use for viral infections and self-medication were common. Targeted public health education, pharmacy-based interventions, stricter regulation of non-prescription antibiotic dispensing, and improved physician patient communication are needed to promote responsible antibiotic use in Iran.