Olanzapine's Impact on Oral Health in Patients with Schizophrenia: Research Progress on Effects and Mechanisms

Background : Olanzapine, a first-line atypical antipsychotic used in over 60% of clinical cases, induces dose-dependent oral impairments (xerostomia, caries, periodontitis) with a 35%-78% incidence in long-term use (≥3 months). Existing studies lack large-sample evidence from East Asians, focus on single adverse reactions, and have fragmented intervention strategies, failing to meet precise diagnosis needs. Objective : This review summarizes olanzapine-induced oral damage characteristics and molecular mechanisms, proposes GRADE-graded individualized oral management plans, clarifies East Asians’ risk thresholds and intervention priorities, and provides evidence for clinical practice. Methods : Following PRISMA 2020 guidelines, we searched PubMed, Web of Science, CNKI (2018-2025), including 24 high-quality studies. Data from NHANES 2017-2020 (586 cases) and 4 Chinese studies (832 cases) were analyzed via random-effects models and multivariate regression. Outcome indicators followed WHO oral health survey methods and 2017 periodontal disease classification. Results : East Asians are more susceptible to olanzapine’s oral toxicity (xerostomia: 42%-75%; caries: 51.3%), with a sharp risk increase at ≥8 mg/day (OR=2.73, P<0.001). Core mechanisms include M1/M3 receptor blockade-induced salivary hyposecretion, hBD-2/NF-κB-mediated dysbiosis, and TNF-α/IL-6 inflammatory crosstalk. Conclusion : Olanzapine-induced oral impairments show significant ethnic heterogeneity, with higher sensitivity in East Asians linked to M1 receptor polymorphism and high-refined carbohydrate diets. Stomatological departments should establish specialized management for olanzapine users, including 4-monthly screenings and dose warnings for ≥8 mg/day, combined with targeted interventions.