Gingival hyperplasia as an uncommon adverse effect of quetiapine: a case report

Abstract Quetiapine, a widely used atypical antipsychotic, is indicated for multiple psychiatric conditions and has well-established side effects. However, oral complications like gingival hyperplasia and gingivitis are rare and underrecognized. We present a case of quetiapine-induced gingival hyperplasia in a general adult psychiatry patient, which to our knowledge is the first case published to date. A 31-year-old male with treatment-resistant major depressive disorder and borderline personality traits developed severe gingival hyperplasia and gingivitis, along with systemic side effects such as blurred vision and weight gain during quetiapine titration to 300 mg/day. His symptoms resolved after discontinuation but recurred briefly upon reintroduction. Adjusting his medication regimen enhanced his oral health, affirming a causal relationship; however, it complicated mood control. This case illustrates that even moderate quetiapine doses can manifest serious oral complications. Physicians should monitor for these issues, as they have notable effects on patients’ quality of life and treatment adherence. This report emphasizes the importance of raising awareness and patient education regarding oral side effects, with an interdisciplinary approach warranted.