Abstract
<jats:p>Folie à famille is an uncommon form of shared psychotic disorder in which a dominant family member induces fixed delusional beliefs in several relatives. Over the past 10 years, only about 60 cases of folie à famille, shared psychotic disorder, or similar familywide delusional syndromes have been documented in PubMed/PMC-indexed literature that fully replicate the features observed in our patient. This is a case of a 71-year-old retired doctor who developed persecutory delusions directed at a deceased colleague and gradually induced identical delusional beliefs in both his wife and daughter over a 13-year period, leading to near total social isolation. The family was first identified clinically when a medical emergency—acute kidney injury and dyselectrolytaemia—made medical access unavoidable. During the inpatient stay, he was started on oral and parenteral anti psychotics. Mrs. S was treated with antipsychotics, and her daughter with antipsychotics and antidepressants. All three underwent structured psychoeducation and regular follow-up, achieving improved insight and gradual social reintegration. This case is novel for its unusually long duration before recognition, its inclusion of three family members in concord with the inducer, its discovery via medical rather than psychiatric crisis, and its successful non-separative therapeutic approach. Notably, despite all three being medical professionals, entrenched stigma and adverse psychosocial factors contributed to protracted delays in seeking psychiatric care. Further challenges arising from comorbid medical conditions and treatment-related adverse effects may also contribute to delayed or diminished treatment adherence. This case thus adds to the limited recent literature and offers evidence that insight-oriented, family-engaged treatment may succeed even in deeply entrenched folie à famille.</jats:p>