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Delusions of Parasitosis Follow-up

  • Author: Noah S Scheinfeld, JD, MD, FAAD; Chief Editor: Dirk M Elston, MD  more...
Updated: Jan 20, 2016

Further Outpatient Care

After medication has cleared the delusions of parasitosis, the agent should be continued for several months and then discontinued. Often, patients come to think that the medication has killed the bugs, and many (but not all) have a remission of their delusions.



If delusions of parasitosis are not treated, scarring can result. The patient's entire life and family may be disrupted by their distress and attempts at treatment.

Therapy for delusions of parasitosis can cause adverse effects. Pimozide can result in tardive dyskinesia and akathisia. Extrapyramidal reactions have been reported to occur in approximately 10-15% of patients taking pimozide. Pimozide can have cardiotoxic effects at high doses. It may cause ECG changes such as prolongation of the QT interval, T-wave changes, and the appearance of U waves.

Lim et al[53] noted an incidence of camphor-related, self-inflicted keratoconjunctivitis secondary to delusions of parasitosis.



Many patients with delusions of parasitosis refuse treatment and are lost to follow-up. For those patients who can be convinced to undertake treatment, the prognosis for a remission of the delusions is good.


Patient Education

Patients must be reassured that they are not alone and that the physician will listen to them and sincerely desires to help them to get better. While one should not say anything to confirm the delusion, it is usually not helpful to forcefully confront patients with delusions of parasitosis.

Statements such as the following might be helpful: "I know you feel strongly that there are parasites here, and I'm sure that you itch severely, but I cannot prove that parasites are or have been the cause of your problem."

For patient education resources, see the Mental Health and Behavior Center.

Contributor Information and Disclosures

Noah S Scheinfeld, JD, MD, FAAD Assistant Clinical Professor, Department of Dermatology, Weil Cornell Medical College; Consulting Staff, Department of Dermatology, St Luke's Roosevelt Hospital Center, Beth Israel Medical Center, New York Eye and Ear Infirmary; Assistant Attending Dermatologist, New York Presbyterian Hospital; Assistant Attending Dermatologist, Lenox Hill Hospital, North Shore-LIJ Health System; Private Practice

Noah S Scheinfeld, JD, MD, FAAD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Serve(d) as a speaker or a member of a speakers bureau for: Abbvie<br/>Received income in an amount equal to or greater than $250 from: Optigenex<br/>Received salary from Optigenex for employment.

Specialty Editor Board

David F Butler, MD Section Chief of Dermatology, Central Texas Veterans Healthcare System; Professor of Dermatology, Texas A&M University College of Medicine; Founding Chair, Department of Dermatology, Scott and White Clinic

David F Butler, MD is a member of the following medical societies: American Medical Association, Alpha Omega Alpha, Association of Military Dermatologists, American Academy of Dermatology, American Society for Dermatologic Surgery, American Society for MOHS Surgery, Phi Beta Kappa

Disclosure: Nothing to disclose.

Jeffrey Meffert, MD Associate Clinical Professor of Dermatology, University of Texas School of Medicine at San Antonio

Jeffrey Meffert, MD is a member of the following medical societies: American Academy of Dermatology, American Medical Association, Association of Military Dermatologists, Texas Dermatological Society

Disclosure: Nothing to disclose.

Chief Editor

Dirk M Elston, MD Professor and Chairman, Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina College of Medicine

Dirk M Elston, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

Additional Contributors

Franklin Flowers, MD Department of Dermatology, Professor Emeritus Affiliate Associate Professor of Pathology, University of Florida College of Medicine

Franklin Flowers, MD is a member of the following medical societies: American College of Mohs Surgery

Disclosure: Nothing to disclose.

  1. Savely VR, Leitao MM, Stricker RB. The mystery of Morgellons disease: infection or delusion?. Am J Clin Dermatol. 2006. 7(1):1-5. [Medline].

  2. Koblenzer CS. The challenge of Morgellons disease. J Am Acad Dermatol. 2006 Nov. 55(5):920-2. [Medline].

  3. Waddell AG, Burke WA. Morgellons disease?. J Am Acad Dermatol. 2006 Nov. 55(5):914-5. [Medline].

  4. Murase JE, Wu JJ, Koo J. Morgellons disease: a rapport-enhancing term for delusions of parasitosis. J Am Acad Dermatol. 2006 Nov. 55(5):913-4. [Medline].

  5. Marris E. Mysterious 'Morgellons disease' prompts US investigation. Nat Med. 2006 Sep. 12(9):982. [Medline].

  6. Harvey WT. Morgellons disease. J Am Acad Dermatol. 2007 Apr. 56(4):705-6. [Medline].

  7. Walling HW, Swick BL. Psychocutaneous syndromes: a call for revised nomenclature. Clin Exp Dermatol. 2007 May. 32(3):317-9. [Medline].

  8. Hylwa SA, Foster AA, Bury JE, Davis MD, Pittelkow MR, Bostwick JM. Delusional infestation is typically comorbid with other psychiatric diagnoses: review of 54 patients receiving psychiatric evaluation at Mayo Clinic. Psychosomatics. 2012 May. 53(3):258-65. [Medline].

  9. Fellner MJ. New findings in delusions of parasitosis. Skinmed. 2012 Mar-Apr. 10(2):72-4. [Medline].

  10. Reichenberg JS, Magid M, Jesser CA, Hall CS. Patients labeled with delusions of parasitosis compose a heterogenous group: a retrospective study from a referral center. J Am Acad Dermatol. 2013 Jan. 68(1):41-6, 46.e1-2. [Medline].

  11. Freudenmann RW, Lepping P, Huber M, et al. Delusional infestation and the specimen sign: a European multicentre study in 148 consecutive cases. Br J Dermatol. 2012 Aug. 167(2):247-51. [Medline].

  12. Levin EC, Gieler U. Delusions of parasitosis. Semin Cutan Med Surg. 2013 Jun. 32(2):73-7. [Medline].

  13. Heller MM, Wong JW, Lee ES, Ladizinski B, Grau M, Howard JL, et al. Delusional infestations: clinical presentation, diagnosis and treatment. Int J Dermatol. 2013 Jul. 52(7):775-83. [Medline].

  14. Patel V, Koo JY. Delusions of parasitosis; suggested dialogue between dermatologist and patient. J Dermatolog Treat. 2015 Oct. 26(5):456-60. [Medline].

  15. Monk BE, Rao YJ. Delusions of parasitosis with fatal outcome. Clin Exp Dermatol. 1994 Jul. 19(4):341-2. [Medline].

  16. Aw DC, Thong JY, Chan HL. Delusional parasitosis: case series of 8 patients and review of the literature. Ann Acad Med Singapore. 2004 Jan. 33(1):89-94. [Medline].

  17. Bouree P, Benattar B, Perivier S. [Ekbom syndrome or delusional parasitosis]. Rev Prat. 2007 Mar 31. 57(6):585-9. [Medline].

  18. Goddard J. Seasonality of delusions of parasitosis. J Agromedicine. 2003. 9(1):23-6. [Medline].

  19. Vila-Rodriguez F, Macewan BG. Delusional parasitosis facilitated by web-based dissemination. Am J Psychiatry. 2008 Dec. 165(12):1612. [Medline].

  20. Edison KE, Slaughter JR, Hall RD. Psychogenic parasitosis: a therapeutic challenge. Mo Med. 2007 Mar-Apr. 104(2):132-7; quiz 137-8. [Medline].

  21. Le L, Gonski PN. Delusional parasitosis mimicking cutaneous infestation in elderly patients. Med J Aust. 2003 Aug 18. 179(4):209-10. [Medline].

  22. Bury JE, Bostwick JM. Iatrogenic delusional parasitosis: a case of physician-patient folie a deux. Gen Hosp Psychiatry. 2010 Mar-Apr. 32(2):210-2. [Medline].

  23. Thakkar A, Ooi KG, Assaad N, Coroneo M. Delusional infestation: are you being bugged?. Clin Ophthalmol. 2015 Jun. 2;9:967-70. [Medline].

  24. Gassiep I, Griffin PM. Delusions of disseminated fungosis. Case Rep Infect Dis. 2014. 2014:458028. [Medline].

  25. Koo J, Lee CS. Delusions of parasitosis. A dermatologist's guide to diagnosis and treatment. Am J Clin Dermatol. 2001. 2(5):285-90. [Medline].

  26. Swick BL, Walling HW. Drug-induced delusions of parasitosis during treatment of Parkinson's disease. J Am Acad Dermatol. 2005 Dec. 53(6):1086-7. [Medline].

  27. Lopez PR, Rachael T, Leicht S, Smalligan RD. Gabapentin-induced delusions of parasitosis. South Med J. 2010. 103:711-2. [Medline].

  28. Steinert T, Studemund H. Acute delusional parasitosis under treatment with ciprofloxacin. Pharmacopsychiatry. 2006 Jul. 39(4):159-60. [Medline].

  29. Tran TM, Browning J, Dell ML. Psychosis with paranoid delusions after a therapeutic dose of mefloquine: a case report. Malar J. 2006 Aug 23. 5:74. [Medline].

  30. Krauseneck T, Soyka M. Delusional parasitosis associated with pemoline. Psychopathology. 2005 Mar-Apr. 38(2):103-4. [Medline].

  31. Guarneri F, Guarneri C, Mento G, Ioli A. Pseudo-delusory syndrome caused by Limothrips cerealium. Int J Dermatol. 2006 Mar. 45(3):197-9. [Medline].

  32. Ghaffari-Nejad A, Toofani K. Delusion of oral parasitosis in a patient with major depressive disorder. Arch Iran Med. 2006 Jan. 9(1):76-7. [Medline].

  33. Duggal H, Singh I. Delusional parasitosis as a presenting feature of dementia. J Neuropsychiatry Clin Neurosci. 2010 Winter. 22(1):123.E11-12. [Medline].

  34. Trager MJ, Hwang TN, McCulley TJ. Delusions of parasitosis of the eyelids. Ophthal Plast Reconstr Surg. 2008 Jul-Aug. 24(4):317-9. [Medline].

  35. Huber M, Karner M, Kirchler E, Lepping P, Freudenmann RW. Striatal lesions in delusional parasitosis revealed by magnetic resonance imaging. Prog Neuropsychopharmacol Biol Psychiatry. 2008 Dec 12. 32(8):1967-71. [Medline].

  36. Hylwa SA, Bury JE, Davis MD, Pittelkow M, Bostwick JM. Delusional Infestation, Including Delusions of Parasitosis: Results of Histologic Examination of Skin Biopsy and Patient-Provided Skin Specimens. Arch Dermatol. May 2011. [Medline].

  37. Patel V, Koo JY. Delusions of Parasitosis; Suggested Dialogue between Dermatologist and Patient. J Dermatolog Treat. 2014 Dec 9. 1-15. [Medline].

  38. Söderfeldt Y, Groß D. Information, consent and treatment of patients with morgellons disease: an ethical perspective. Am J Clin Dermatol. 2014 Apr. 15(2):71-6. [Medline].

  39. Scheinfeld N. Delusions of parasitiosis: a case with a review of its course and treatment. Skinmed. 2003 Nov-Dec. 2(6):376-8. [Medline].

  40. Wenning MT, Davy LE, Catalano G, Catalano MC. Atypical antipsychotics in the treatment of delusional parasitosis. Ann Clin Psychiatry. 2003 Sep-Dec. 15(3-4):233-9. [Medline].

  41. Reichenberg JS, Magid M, Drage LA. A cure for delusions of parasitosis. J Eur Acad Dermatol Venereol. 2007 Nov. 21(10):1423-4. [Medline].

  42. Rocha FL, Hara C. Aripiprazole in delusional parasitosis: Case report. Prog Neuropsychopharmacol Biol Psychiatry. 2007 Apr 13. 31(3):784-6. [Medline].

  43. Ladizinski B, Busse KL, Bhutani T, Koo JY. Aripiprazole as a viable alternative for treating delusions of parasitosis. J Drugs Dermatol. Dec 2010. 9:1531-2. [Medline].

  44. Szepietowski JC, Salomon J, Hrehorow E, Pacan P, Zalewska A, Sysa-Jedrzejowska A. Delusional parasitosis in dermatological practice. J Eur Acad Dermatol Venereol. 2007 Apr. 21(4):462-5. [Medline].

  45. Elmer KB, George RM, Peterson K. Therapeutic update: use of risperidone for the treatment of monosymptomatic hypochondriacal psychosis. J Am Acad Dermatol. 2000 Oct. 43(4):683-6. [Medline].

  46. Friedmann AC, Ekeowa-Anderson A, Taylor R, Bewley A. Delusional parasitosis presenting as folie à trois: successful treatment with risperidone. Br J Dermatol. 2006 Oct. 155(4):841-2. [Medline].

  47. Meehan WJ, Badreshia S, Mackley CL. Successful treatment of delusions of parasitosis with olanzapine. Arch Dermatol. 2006 Mar. 142(3):352-5. [Medline].

  48. Freudenmann RW, Schönfeldt-Lecuona C. Delusional parasitosis: treatment with atypical antipsychotics. Ann Acad Med Singapore. 2005 Jan. 34(1):141-2; author reply 142. [Medline].

  49. Atilganoglu U, Ugurad I, Arikan M, Ergun SS. Monosymptomatic hypochondriacal psychosis presenting with recurrent oral mucosal ulcers and multiple skin lesions responding to olanzapine treatment. Int J Dermatol. 2006 Oct. 45(10):1189-92. [Medline].

  50. van Vloten WA. Pimozide: use in dermatology. Dermatol Online J. 2003 Mar. 9(2):3. [Medline].

  51. Fellner MJ, Majeed MH. Tales of bugs, delusions of parasitosis, and what to do. Clin Dermatol. 2009 Jan-Feb. 27(1):135-8. [Medline].

  52. Bennassar A, Guilabert A, Alsina M, Pintor L, Mascaro JM Jr. Treatment of delusional parasitosis with aripiprazole. Arch Dermatol. 2009 Apr. 145(4):500-1. [Medline].

  53. Lim GC, Chen YF, Liu L, Huang SC, Lin KK, Hsiao CH. Camphor-related self-inflicted keratoconjunctivitis complicating delusions of parasitosis. Cornea. 2006 Dec. 25(10):1254-6. [Medline].

  54. Gee SN, Zakhary L, Keuthen N, Kroshinsky D, Kimball AB. A survey assessment of the recognition and treatment of psychocutaneous disorders in the outpatient dermatology setting: how prepared are we?. J Am Acad Dermatol. 2013 Jan. 68(1):47-52. [Medline].

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