shared paranoid disorder


Summary: A condition in which closely related persons, usually in the same family, share the same delusions.

Top Publications

  1. Mentjox R, van Houten C, Kooiman C. Induced psychotic disorder: clinical aspects, theoretical considerations, and some guidelines for treatment. Compr Psychiatry. 1993;34:120-6 pubmed
    ..Long-term results are seldom mentioned. On the basis of theoretical considerations, interventions that aim at separation in psychological terms are necessary to achieve favorable long-term treatment results. ..
  2. Wenning M, Davy L, Catalano G, Catalano M. Atypical antipsychotics in the treatment of delusional parasitosis. Ann Clin Psychiatry. 2003;15:233-9 pubmed
    ..We will also comment on the possible role of serotonergic antidepressants in the treatment of these patients. ..
  3. Reif A, Pfuhlmann B. Folie a deux versus genetically driven delusional disorder: case reports and nosological considerations. Compr Psychiatry. 2004;45:155-60 pubmed
    ..Thus, thorough psychopathological examination in suspected folie a deux settings can help to obtain valid diagnoses. ..
  4. Shiwach R, Sobin P. Monozygotic twins, folie à deux and heritability: a case report and critical review. Med Hypotheses. 1998;50:369-74 pubmed
    ..In the light of this paradox, nosological status of this disorder and the sociogenic and genetic factors are critically discussed. ..
  5. Dippel B, Kemper J, Berger M. Folie à six: a case report on induced psychotic disorder. Acta Psychiatr Scand. 1991;83:137-41 pubmed
    ..The main factor in the development of this shared paranoid disorder seems to have been the dominant personality of the inducer...
  6. Petrikis P, Andreou C, Garyfallos G, Karavatos A. Incubus syndrome and folie à deux: a case report. Eur Psychiatry. 2003;18:322 pubmed
  7. Wehmeier P, Barth N, Remschmidt H. Induced delusional disorder. a review of the concept and an unusual case of folie à famille. Psychopathology. 2003;36:37-45 pubmed
    Induced delusional disorder (or shared paranoid disorder), also known as folie à deux, is a fairly uncommon disturbance characterized by the presence of similar psychotic symptoms in two or more individuals...
  8. Joshi K, Frierson R, Gunter T. Shared psychotic disorder and criminal responsibility: a review and case report of folie à trois. J Am Acad Psychiatry Law. 2006;34:511-7 pubmed
    ..quot; Finally, we compare shared psychotic disorder, culturally based belief systems, and religious cults, with a focus on their common and contrasting characteristics. ..
  9. Newman W, Harbit M. Folie a deux and the courts. J Am Acad Psychiatry Law. 2010;38:369-75 pubmed
    ..It is difficult to make a reliable diagnosis of a condition that is, to date, not well validated. The authors discuss possible directions for future research and suggest methods for examining evaluees with suspected folie à deux. ..

More Information


  1. Alonso L, Jeffrey W. Mental illness complicated by the santeria belief in spirit possession. Hosp Community Psychiatry. 1988;39:1188-91 pubmed
    ..Rather, it may be a nonspecific symptom of a variety of mental illnesses and should be evaluated in the context of the patient's overall belief system and ability to carry out usual activities. ..
  2. Kraya N, Patrick C. Folie à deux in forensic setting. Aust N Z J Psychiatry. 1997;31:883-8 pubmed
  3. Silveira J, Seeman M. Shared psychotic disorder: a critical review of the literature. Can J Psychiatry. 1995;40:389-95 pubmed
    ..hallucinations were common; 6. the majority of dyads (67.3%) were socially isolated. SPD probably occurs in premorbidly disposed individuals in the context of social isolation which is shared with a psychotic person. ..
  4. Chapman A, Vieira e Silva D. Folie à deux dissociative disorder in prepubertal children. Report of two cases with EEGs. Arq Neuropsiquiatr. 1998;56:646-9 pubmed
    ..Speculations about the emotional and interpersonal causes of this illness in these two patients are given. ..
  5. Kelly B. Folie a plusieurs: forensic cases from nineteenth-century Ireland. Hist Psychiatry. 2009;20:47-60 pubmed
  6. Howard R. Induced psychosis. Br J Hosp Med. 1994;51:304-7 pubmed
    ..A guide to the terminology, aetiology, diagnosis and treatment of induced psychoses is given, together with a description of two cases of folie à deux. ..
  7. Caduff F, Hubschmid T. [Folie à deux. Review of the literature and an unusual case]. Nervenarzt. 1995;66:73-7 pubmed
    ..Of special interest is the personality of the protagonists, their psychological assessment, and the so far ineffective therapeutic interventions that have been undertaken in efforts to save the children. ..
  8. Pignotti M. [Parental alienation syndrome (PAS): unknown in medical settings, endemic in courts]. Recenti Prog Med. 2013;104:54-8 pubmed publisher
    ..In severe cases, PAS becomes a new and efficient tool of intra-familiar violence. The treatment of severe cases is to stop any contact between mother and children. The resort to PAS in Courts must be strongly rejected. ..
  9. Teixeira J, Mota T, Fernandes J. Folie à deux: a case report. Clin Schizophr Relat Psychoses. 2013;7:93-6 pubmed publisher
    ..Many years after it was first described, folie à deux is still an interesting and challenging disorder to psychiatrists, especially concerning its pathophysiology and treatment. ..
  10. De la Fuente J. [Psychosis shared by 4 subjects]. Acta Psychiatr Belg. 1991;91:83-95 pubmed
    ..Induced psychotic disorder is a very rare clinical picture. We describe here one occurrence which included four members of the same family. A brief review of the literature is made and several etiological factors are discussed. ..
  11. Ilechukwu S. Is there a shared somatic disorder? Communication of non delusional symptoms in Nigeria. Can J Psychiatry. 1992;37:699-702 pubmed
  12. Cuhadaroğlu Cetin F. Folie à famille and separation-individuation. Eur Child Adolesc Psychiatry. 2001;10:194-9 pubmed
    ..The case history, treatment and follow-up of a family sharing the same delusion are presented in this article. The characteristics of separation-individuation of this pathological condition and its treatment are discussed. ..
  13. Colombo G, Caimi M, Donà G. Shared Ekbom's syndrome. A case study. Eur Psychiatry. 2004;19:115-6 pubmed
  14. Florez G, Gómez Reino I. Simultaneous madness in twin sisters. Eur Psychiatry. 2001;16:501-2 pubmed
  15. Salganik I, Evgeny S, Galina P. Facilitation in inducing folie a deux through healthy precipitator. Am J Psychiatry. 2006;163:1453 pubmed
  16. Patel A, Arnone D, Ryan W. Folie a deux in bipolar affective disorder: a case report. Bipolar Disord. 2004;6:162-5 pubmed
    ..This case highlights the unusual and rare phenomenon of folie a deux occurring in the context of BAD. It also suggests current difficulty in defining folie a deux as an entity according to current diagnostic criteria. ..
  17. Shimizu M, Kubota Y, Toichi M, Baba H. Folie à deux and shared psychotic disorder. Curr Psychiatry Rep. 2007;9:200-5 pubmed
    ..The controversial issue of the etiology of FAD-association of subjects or genetically driven psychosis-was re-examined in light of recent studies. ..
  18. Vizuete C, De la Fuente J. [An electromagnetic problem]. Actas Luso Esp Neurol Psiquiatr Cienc Afines. 1993;21:23-8 pubmed
    ..Induced psychotic disorder in infrequent. We report a case in which four members of the same family were affected. The bibliography is reviewed and certain etiological factors implicated in our case are discussed. ..
  19. Yazar M, Erbek E, Eradamlar N, Alpkan L. The Seven Sleepers: a folie à deux case originating from a religious-cultural belief. Transcult Psychiatry. 2011;48:684-92 pubmed publisher
    ..These mystical delusions were derived from the Anatolian legend of The Seven Sleepers. The case resulted in the death of the wife. This study illustrates the role of cultural and religious factors in folie à deux. ..
  20. Draper B, Cole A. Folie à deux and dementia. Aust N Z J Psychiatry. 1990;24:280-2 pubmed
    ..A case is described in which both partners with folie à deux suffered from an Alzheimer type dementia. The development and management of folie à deux in dementia is discussed. ..
  21. Ananth J, Kaur A, Djenderedjian A. Simultaneous Folie à Deux and Capgras syndrome. Psychiatr J Univ Ott. 1990;15:41-3 pubmed
    ..Both of his parents shared the same delusions with the patient. A dynamic explanation is provided for the simultaneous occurrence of both syndromes. The case report and the management of this patient may be of interest to clinicians. ..
  22. Wormstall H, Krauter T. [Travel as a stabilizing factor in folie a deux?]. Psychiatr Prax. 1992;19:81-3 pubmed
    ..The history of the disease pattern of "folie à deux", or double insanity, is described, as well as the present-day definitions, and the case report is set against this background. ..
  23. Greenberg D, Witztum E, Buchbinder J. Mysticism and psychosis: the fate of Ben Zoma. Br J Med Psychol. 1992;65 ( Pt 3):223-35 pubmed
    ..Four eminent Rabbis entered the garden of mystical speculation. Ben Azzai glimpsed and died. Ben Zoma glimpsed and was damaged (lost his sanity). Elisha ben Avuyah lost his faith. Rabbi Akiva departed in peace. ..
  24. Krelling R, Cordeiro Q, Vallada H. [Implications of etiopathogenic aspects in the treatment of folie à deux]. Rev Assoc Med Bras (1992). 2007;53:291 pubmed
  25. Dodig Curkovic K, Curković M, Degmecić D, Delalle M, Mihanovic M, Filakovic P. Shared psychotic disorder ("folie a deux") between mother and 15 years old son. Coll Antropol. 2008;32:1255-8 pubmed
    ..With complete psychiatric anamnesis, clinical interview, psychological testing, EEG (examination-electroencephalography) examination and control examinations we came to the diagnosis and efficacious pharmacological intervention for son. ..
  26. Prochwicz K. [Insanity of two. Clinical symptomatology and psychosocial factors of induced paranoid disorder]. Psychiatr Pol. 2009;43:19-30 pubmed
    ..Psychological, social and demographical factors play an important role in emergence of shared paranoid disorders. ..
  27. Richard Devantoy S, Chocard A, Bourdel M, Gohier B, Duflot J, Lhuillier J, et al. [Homicide and major mental disorder: what are the social, clinical, and forensic differences between murderers with a major mental disorder and murderers without any mental disorder?]. Encephale. 2009;35:304-14 pubmed publisher
    ..To these factors should be added the dynamic characteristics of the meeting of the protagonists. ..
  28. Grover S, Gupta N. Shared obsessive-compulsive disorder. Psychopathology. 2006;39:99-101 pubmed
    ..Shared obsessions could represent the continuum concept of obsessions and delusions, and their relationship needs to be evaluated in greater detail. ..
  29. Berbara C, Almeida S, Cermelli Reber M, Cortez S, Gonzales M. ["Folie à Famille", an interdisciplinary experience from a clinical and therapeutic stance]. Vertex. 2010;21:105-13 pubmed
    ..A full review of the concept of "Folie à Famille" will be provided as described previously in the literature. Observational analytic descriptive study. ..
  30. Shimizu M, Kubota Y, Calabrese J, Toichi M, Kato S, Baba H. Analysis of delusional statements from 15 Japanese cases of 'Folie à Deux'. Psychopathology. 2006;39:92-8 pubmed
    ..Further studies on FAD are needed, however, the present method of examining the SP seems to be useful in order to investigate the psychological mechanism of delusion formation between plural subjects. ..
  31. Nielssen O, Langdon R, Large M. Folie à deux homicide and the two-factor model of delusions. Cogn Neuropsychiatry. 2013;18:390-408 pubmed publisher
    ..Folie à deux demonstrates the need to consider the exogenous source of delusional content in many patients. ..
  32. Bourgeois M, Duhamel P, Verdoux H. Delusional parasitosis: folie à deux and attempted murder of a family doctor. Br J Psychiatry. 1992;161:709-11 pubmed
    ..The case illustrates the intractable nature and potential dangerousness of some of these cases, and their affinity to paranoia. ..
  33. Arenz D, Stippel A. [Communicated insanity, folie a deux and shared psychotic disorder. Different concepts and a case from Mallorca]. Fortschr Neurol Psychiatr. 1999;67:249-55 pubmed
    ..We report a case of an induced psychosis in two women and give particular attention to the German psychopathological tradition because of still existing clinical relevance. ..
  34. Lerner V, Greenberg D, Bergman J. Daughter-mother folie à deux: immigration as a trigger for role reversal and the development of folie à deux. Isr J Psychiatry Relat Sci. 1996;33:260-4 pubmed
    ..Folie à deux only appeared in the previously dominant member once she became the dependent member. Follow-up showed resolution of the folie à deux with no change in the recent reversal of roles. ..
  35. Signer S, Isbister S. Capgras syndrome, de Clérambault's syndrome, and folie à deux. Br J Psychiatry. 1987;151:402-4 pubmed
    ..Capgras and de Clérambault's syndromes appear together more commonly than is apparent in the literature. Review of these cases shows a strong association with severe affective disorder. ..
  36. Harmon C, Rames L. Folie à deux in identical twins. Hosp Community Psychiatry. 1994;45:1238-9 pubmed
  37. Metzger W, Steinert T, Schmidt Michel P. [Timing of occult practices-induced paranoid hallucinatory psychosis in 2 sisters]. Psychiatr Prax. 1996;23:199-200 pubmed
  38. Musalek M, Kutzer E. The frequency of shared delusions in delusions of infestation. Eur Arch Psychiatry Neurol Sci. 1990;239:263-6 pubmed
    ..Cases of induced delusions are also described in which attending physicians act as "inducers". ..
  39. Scheff T. A social/emotional theory of 'mental illness'. Int J Soc Psychiatry. 2013;59:87-92 pubmed publisher
    ..To the extent that this theory is true, we would need to rename the field using non-medical terms, such as emotional/social dysfunction. ..
  40. Moss P, Pearce P. The French connection: folie à quatre. Can J Psychiatry. 1989;34:55-7 pubmed
    ..Difficulties in establishing the family's true identity and problems raised in reuniting the family, while the mother was felt to be concealing her remaining delusions, are discussed. ..
  41. Gunter M, Boos R. [Significance of "abnormal reaction susceptibility" of adolescents in Munchausen by proxy syndrome. Simulation, folie à deux, induced artefact disease or what else?]. Nervenarzt. 1994;65:307-12 pubmed
    ..The same reactions can for example be seen also in cases of sexual abuse. A bigger sample of patients needs to be investigated to confirm our considerations. ..
  42. Weiss K. Hoarding, hermitage, and the law: why we love the collyer brothers. J Am Acad Psychiatry Law. 2010;38:251-7 pubmed
  43. Jana A, Praharaj S, Sarkar S, Dotivala K, Chabungbam G. [Folie á deux between two unrelated individuals]. Turk Psikiyatri Derg. 2009;20:299-304 pubmed
    ..Premorbidly, there were no features suggestive of dependency or low intelligence in the secondary case. After separation from the primary case, improvement was observed about 7 weeks after beginning risperidone treatment (6 mg/day). ..
  44. Becker E. [Induction of obsessions--folie a deux]. Ugeskr Laeger. 1993;155:2779-82 pubmed
    ..The cases show the characteristics in folie à deux: 1. An intimate relationship; 2. Social isolation; 3. Delusions similar in content. Ways of treatment are described. ..
  45. Grellner W, Krull F. [Unusual motivation in double suicide of a lesbian couple. Phenomenology, psychodynamics and influence of contemporary values]. Arch Kriminol. 1996;198:65-72 pubmed
    ..The case is well-documented by diary records and will be discussed under phenomenological and psychodynamic aspects. Typical and atypical criteria of double suicides are featured. ..
  46. Yoonas Z, Akintan O, Sandson N, Gorman J. Shared psychotic disorder and mental retardation. J Psychiatr Pract. 2007;13:273-7 pubmed
  47. Caribé A, Daltro Oliveira R, Araújo R, Cardoso A, Guimarães P, Miranda Scippa A, et al. Systemic lupus, folie a trois and homicide. Compr Psychiatry. 2013;54:1032-3 pubmed publisher
    ..We present a case report of folie a trois resulting in murder, secondary to acute psychosis in SLE. ..
  48. Kim C, Kim J, Lee M, Kang M. Delusional parasitosis as 'folie a deux'. J Korean Med Sci. 2003;18:462-5 pubmed
    ..We experienced delusional parasitosis as Folie a Deux between a mother and her son and successfully treated them through early psychiatric intervention. We believe that attention should be drawn to DP with SPD. ..
  49. Ghaziuddin M. Folie à deux and mental retardation: review and case report. Can J Psychiatry. 1991;36:48-9 pubmed
    ..The need for an increased awareness of the existence of mental illness in the mentally handicapped is also emphasized. ..
  50. Roth D. How "mild" is mild Munchausen syndrome by proxy?. Isr J Psychiatry Relat Sci. 1990;27:160-7 pubmed
    ..It is thus suggested that mild cases of MSbP may be indicators of severely disturbed mother-child relationships, raising important questions about their proper management. ..
  51. Brown M, King E, Barraclough B. Nine suicide pacts. A clinical study of a consecutive series 1974-93. Br J Psychiatry. 1995;167:448-51 pubmed
    ..Mental disorder is common in those who enter suicide pacts (mainly depression, with alcohol dependence rare). Motivations for suicide appear to be relief of mental disorder and pain. ..
  52. Berman A. Dyadic death: a typology. Suicide Life Threat Behav. 1996;26:342-50 pubmed
    ..The proposed typology varies by levels of dominance, dependence-enmeshment, and the presence or absence of hostility in and between partners. ..
  53. Tenyi T, Tamas L, Pasztor A, Herold R, Trixler M. ["Folie a deux hallucinatoire"--a new case of induced hallucinatory psychosis. A new entity?]. Orv Hetil. 1999;140:1417-8 pubmed
    ..They deal with the nosological position of "folie a deux hallucinatoire" (induced hallucinatory psychosis) and integrate the consequences of the case to the general psychopathological theory of hallucinations. ..