1School of Medicine, McMaster University, Hamilton, ON, Canada
2Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada
Conflict of interest: None reported.
Up to a third of dermatology outpatients have a significant psychiatric issue complicating their skin complaint. Although the ideal would frequently involve psychiatric assessment, those with comorbid mental illness often refuse psychiatric referral. As a result, it is imperative that dermatologists be mindful of psychiatric comorbidity in their patients and comfortable with the fundamentals of psychodermatologic diagnosis and therapy. This update summarizes current concepts, relevance, and therapeutics in psychodermatology, including aspects pertinent to depression, anxiety, obsessive-compulsive, impulse-control, and delusional disorders as described in the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5, published in 2013 by the American Psychiatric Association).
Key Words: anxiety, delusional disorder, depression, dermatology, DSM-5, excoriation disorder, obsessive-compulsive disorder, parasitosis,
psychiatry, psychodermatology, trichotillomania
Mind and skin are intimately related. Up to a third of dermatology outpatients have a significant psychiatric issue complicating their skin complaint.1 The dermatologist’s work is far from skin deep; often the most meaningful aspects of management involve success in resolving the psychosocial impact of cutaneous disease. Although the ideal management would frequently involve psychiatric assessment, those with comorbid mental illness often refuse psychiatric referral. As a result, it is imperative that dermatologists be mindful of psychiatric comorbidity in their patients and comfortable with the fundamentals of psychodermatologic diagnosis and therapy.
Categories of Psychodermatology
Psychodermatology covers a broad spectrum of diseases. The four main categories include psychophysiological disorders, primary psychiatric disorders, secondary psychiatric disorders, and cutaneous sensory disorders.2
Psychophysiologic disorders are primary skin diseases modified by psychosomatic factors. These include psoriasis, atopic dermatitis, acne, and hyperhidrosis, all skin conditions that are known to worsen with stress or emotional triggers.3
Primary psychiatric diseases include those that are psychotic, delusional, or obsessive in nature. Examples include delusions of parasitosis, neurotic excoriations, trichotillomania, and factitious disorder. No primary skin lesions will exist in most cases, as skin changes within this category will commonly be self-induced. These patients often lack insight into their condition, and as a result they require tactful clinical care. Note that factitious disorder, which in dermatology involves self-induced or alleged skin pathology without external incentive, is sometimes described as dermatitis artefacta or factitious dermatitis. These terms misleadingly suggest underlying inflammation.
Secondary psychiatric disorders, on the other hand, are psychiatric disturbances caused by skin disease. Depression, anxiety, and social phobias from acne, psoriasis, or alopecia areata are some examples. The morbidity from these diseases is predominantly a consequence of their effect on mental state. As a result, their psychiatric sequelae are often responsive to successful dermatologic therapy.
Cutaneous sensory disorders, like those in the primary psychiatric category, will involve no primary skin changes. Patients may complain of itching, burning, pain, or stinging. Cutaneous sensory disorders may involve a neuropathic etiology.
Several high-yield diagnoses exist within the intersection of dermatology and psychiatry. These include psychotic and delusional disorders, obsessive and impulse-control disorders, depressive disorders, anxiety disorders, and cutaneous sensory disorders. Unfortunately, randomized controlled trials for the specific management of psychocutaneous diseases are sporadic and low-powered when present. Where they are relevant and robust, we will therefore emphasize Canadian guidelines, especially those from the Canadian Network for Mood and Anxiety Treatments (CANMAT) series.4-6
As the following diagnoses can be found within any of the previously described categories, the clinical diagnosis and category remain separate judgments. Treatment should be aimed at the underlying psychopathology, regardless of whether it is primary, secondary, or merely exacerbating skin disease. Neurotic excoriations secondary to depression, psoriasis worsened by depression, and depression secondary to alopecia areata, for example, all warrant a similar therapeutic approach.
Depression is common in our patient population. One review suggests about 30% of patients in the general dermatology practice will have some form of depression. This prevalence compares to 22% in general practice.7 A cross-sectional study identified 10% of 384 dermatology patients with major depression.8 For many skin conditions, the prevalence may be even higher. In an extensive 2014 systematic review, Dowlatshahi et al. found 19% of psoriasis patients studied met the Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM-IV) criteria for major depression.9 More recently, a 2015 4994-patient European cross-sectional multicenter study of dermatology outpatients reported a 12.7% rate of suicidal ideation (compared to 8.3% in the hospital employees used as controls). Psoriasis had a 17.3% association with suicidal ideation, and two-thirds of these patients responded that their ideation was a direct consequence of their skin condition.1 Atopic dermatitis, alopecia, urticaria, pruritus, and vitiligo also correspond to lower mood.10 Degree of itch plays a role, and conversely depression may work to lessen the threshold for pruritus.11 There are concerns that systemic use of corticosteroids or isotretinoin may increase the risk for depression and suicide.12,13 Surprisingly, disease impact does not seem to correlate well with severity, and physicians tend to underestimate the psychological implications of cutaneous disorders.14
The CANMAT guidelines for unipolar depression direct firstline therapeutics for major depressive disorder towards any of the second-generation anti-depressants. These include selective serotonin reuptake inhibitors (SSRIs) and selective norepinephrine reuptake inhibitors (SNRIs) such as escitalopram, sertraline, and venlafaxine. Due to tolerability and safety, tricyclic antidepressants (TCAs) are second-line. In depression, combined treatment with both medication and psychotherapy is superior to either alone.4
Anxiety disorders are associated with typical physical symptoms and excessive worry over finances, relationships, career, and health. They frequently accompany depression, especially in psoriasis, acne, and atopic dermatitis. Although Dalgard et al. found clinical depression present in 10% of 3635 dermatology outpatients, clinical anxiety was present in 17%.1 Both acute and chronic anxiety can contribute to skin disease,15 this link being especially well-documented in the inflammatory dermatoses.
In cases of acute anxiety, benzodiazepine anxiolytics are first-line due to their rapid onset of action. For the chronic management of generalized anxiety disorder, nonetheless, the CANMAT guidelines suggest first-line therapy by means of SSRIs/SNRIs such as sertraline, paroxetine, escitalopram, duloxetine, and venlafaxine, or by means of other agents such as agomelatine and pregabalin.5 Although second-line agents include other medications such as buspirone and hydroxyzine, the SSRIs and SNRIs are especially useful when anxiety coexists with depression.
Obsessive-Compulsive (OCD) and Impulse-Control
A delineating interview question in the 2015 European Society for Dermatology and Psychiatry (ESDaP) position paper on selfinflicted lesions is the following: “How did these lesions occur?” If self-damage is not denied or kept secret by the patient, this points to an obsessive or compulsive etiology.16 In the ESDaP classification, insight is the dividing line between this group and the delusional etiologies of self-inflicted skin lesions. Indeed, patients with obsessive or impulsive disorders will often realize the irrational and inappropriate nature of their intrusive thoughts and persistent behaviors. The DSM-5, in contrast, allows for specifiers within the obsessive compulsive and related disorders – these include “good or fair insight,” “poor insight,” and “absent insight/delusional.”
Impulsive behaviors are usually isolated acts of aggression towards one’s self or others. The dermatologically-significant clinical presentations of the impulsive spectrum include cutting, burning, hitting, and scarring. Compulsive behaviors, on the other hand, are repetitive, often ritualistic, and time-consuming or problematic in work, school, or relationships. They are often associated with an obsessive ideation, as in OCD. The compulsive spectrum disorders present with a more chronic dermatologic picture. Persistent ideas, thoughts, or impulses lead to repetitive behaviors such as skin-picking, hair-pulling, or excessive washing.
New in the DSM-5 are excoriation (skin-picking) disorder and trichotillomania (hair-pulling). Both are examples of compulsive behaviors. Excoriation disorder involves recurrent skin picking resulting in skin lesions, despite repeated attempts to discontinue the behavior. Excoriation disorder is commonly secondary to acne, traditionally called acne excoriée. Trichotillomania, on the other hand, involves recurrent hair pulling resulting in hair loss, again despite repeated attempts to discontinue. A variety of rituals may accompany trichotillomania, including cutting or shaving, scalp-rubbing, hair-biting, or hair-eating.
In either, Gupta and Gupta also describe the potential for dissociative features, especially when skin picking or hair pulling occurs without preceding tension or full awareness.17 These patients will deviate from the typical OCD presentation, and present with mindless, automatic picking or pulling without full awareness of the act. Dissociative features are significant as their presence indicates that treatment must go beyond the standard habit-reversal and SSRI therapy. Rather, patients with dissociative features often have a repressive or post-traumatic stress disorder component of their illness. They require stabilization, assessment of suicide risk, and direct referral to psychiatry.
Important to note is the DSM-5 “Obsessive-Compulsive and Related Disorder Due to Another Medical Condition” and specifier “with skin-picking symptoms.” Many dermatologic conditions, especially psoriasis, atopic dermatitis, and prurigo nodularis, can lead to a skin-picking disorder. Picking, in these cases, is often secondary to itch.
Nail biting (onychophagia), nail tearing (onychotillomania), and lip chewing are examples of the DSM-5 “Body-Focused Repetitive Behavior Disorder” within the obsessive and impulse-control disorders. Self-inflicted cheilitis can also occur from repetitive lip licking.
Body dysmorphic disorder (BDD) is also categorized as an obsessive disorder in the context of the DSM-5. It involves a preoccupation with a perceived physical flaw, and by repetitive behaviors surrounding this flaw. These actions can include excessive grooming, mirror-checking, or self-other comparison. In the DSM-5, BDD is no longer coded as a delusional disorder. As in the other obsessive-compulsive and related disorders, patients can have good insight, poor insight, or absent insight accompanied by delusional beliefs. The prevalence is significant, as BDD encompasses 9-15% of dermatology patients, in comparison to only 2.4% of US adults. Patients with BDD have a high proportion of suicidal ideation, and a quarter attempt suicide in their lifetime.18
CANMAT-recommended first-line pharmacotherapy for OCD and related disorders involves the SSRIs escitalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline. Although commonly used for OCD, the TCA clomipramine is secondline due to poorer tolerability compared to the SSRIs. Cognitive behavioral therapy (CBT), especially exposure and response prevention, is also an effective cornerstone of treatment.19 For OCD and related disorders, combined treatment with both medication and psychotherapy is superior to monotherapy by medication. Combined therapy has not been shown to be superior to CBT alone. Although the CANMAT guidelines describe N-acetylcysteine as a third-line adjunctive therapy, there is promising case report evidence supporting further trials into this glutamatergic agent in the treatment of skin-picking, trichotillomania, and onychophagia.20
Psychotic and Delusional Disorders
In dermatology, the psychotic and delusional disorders most commonly involve what has been historically called monosymptomatic hypochondriacal psychosis. Patients will have an “encapsulated” fixed, false belief and will usually lack any other major psychological disturbance. In contrast to obsessive or compulsive patients, these individuals will lack insight into their condition from the onset of their illness.
The most common psychotic disorder in dermatology involves delusions of parasitosis.21 Here, patients present with the fixed, false belief that their body is infested with a parasite despite the absence of any objective evidence to suggest infestation. They may pick, scrub, or otherwise self-injure, all in an attempt to rid themselves of this parasite. In the DSM-5, delusional parasitosis falls under the category of delusional disorder, somatic type. The DSM-5 no longer separates delusional disorder from shared delusional disorder, traditionally called folie à deux.
Other psychotic disorders in dermatology include delusions of bromosis, in which patients believe that their body emits a strong foul odor, and delusions of dysmorphosis, considered an extreme end of the BDD spectrum in the DSM-IV. Although the DSM-5 categorizes BDD as predominantly obsessive rather than delusional, in clinical reality the distinction between obsession without insight and true delusion is frequently unclear.
Standard treatment for the psychotic and delusional disorders involves antipsychotics such as pimozide, risperidone, and olanzapine.22 For delusional disorders, outcomes do not seem to vary between first and second-generation antipsychotics.23 The challenge, nonetheless, lies in building adequate rapport for the patient to willingly embrace treatment. Often these patients will have had visited many providers, frequently having their concerns dismissed. Empathy is the key, as confrontation can be a barrier to treatment. It is equally important, nonetheless, to avoid confirming the patient’s delusion. Expanding on the above, Patel and Koo suggest verbatim how dermatologists may approach the clinical encounter with a patient suffering from delusions of parasitosis in an elegant 2015 paper.24
Cutaneous Sensory Disorders
In the cutaneous sensory disorders, patients may describe itching, burning, or pain. The causes are sometimes neurologic, as in brachioradial pruritus or postherpetic neuralgia. Formication, on the other hand, describes the sensation of bugs crawling on or under the skin, and can be caused by cocaine or amphetamine abuse (called the
“cocaine bugs”). Although prolonged formication may sometimes precede delusional parasitosis, formication in itself is a cutaneous sensory rather than a delusive state.
Psychopharmacology is only one aspect of the ideal approach to psychodermatology. Cognitive behavioral therapy, for example, has shown excellent efficacy in specific disease states such as depression and OCD.25 Combined pharmacotherapy and psychotherapy is often superior to either alone, as the CANMAT guidelines suggest in acute major depressive disorder. Even though the combination is not yet evidence-based for many other psychopathologies, most psychiatrists will offer a combination of psychotherapy and medication. Other nonpharmacologic modalities are not disease specific, but nonetheless offer global stress reduction, direct psychophysiologic effects, enhanced compliance, and as a result excellent symptom improvement. These include interpersonal therapy, bibliotherapy, relaxation training, behavioral activation, among others. Some have suggested that dermatologists align themselves with a skinemotion specialist, be it a psychiatrist, psychologist, nurse practitioner, counselor, or social worker.26,27
Empathy, expectation management, and cheerleading are aspects of the clinical encounter that can foster a positive therapeutic relationship with a patient presenting with a psychodermatological complaint.2 Dermatologists ought to be mindful of the potential for meaningful improvements in quality of life by addressing the psychiatric dimension of skin disease.
- Dalgard FJ, Gieler U, Tomas-Aragones L, et al. The psychological burden of skin diseases: a cross-sectional multicenter study among dermatological out-patients in 13 European countries. J Invest Dermatol. 2015 Apr;135(4):984-91.
- Leon A, Levin EC, Koo JY. Psychodermatology: an overview. Semin Cutan Med Surg. 2013 Jun;32(2):64-7.
- Huynh M, Gupta R, Koo JY. Emotional stress as a trigger for inflammatory skin disorders. Semin Cutan Med Surg. 2013 Jun;32(2):68-72.
- Lam RW, Kennedy SH, Grigoriadis S, et al; Canadian Network for Mood and Anxiety Treatments (CANMAT). Canadian Network for Mood and Anxiety Treatments (CANMAT) clinical guidelines for the management of major depressive disorder in adults. III. Pharmacotherapy. J Affect Disord. 2009 Oct;117(Suppl 1):S26-43.
- Katzman MA, Bleau P, Blier P, et al; Canadian Anxiety Guidelines Initiative Group on behalf of the Anxiety Disorders Association of Canada/Association Canadienne des troubles anxieux and McGill University, Antony MM, Bouchard S, Brunet A, et al. Canadian clinical practice guidelines for the management of anxiety, posttraumatic stress and obsessive-compulsive disorders. BMC Psychiatry. 2014;14(Suppl 1):S1.
- Schaffer A, McIntosh D, Goldstein BI, et al; Canadian Network for Mood and Anxiety Treatments (CANMAT) Task Force. The CANMAT task force recommendations for the management of patients with mood disorders and comorbid anxiety disorders. Ann Clin Psychiatry. 2012 Feb;24(1):6-22.
- Filakovic P, Biljan D, Petek A. Depression in dermatology: an integrative perspective. Psychiatr Danub. 2008 Sep;20(3):419-25.
- Cohen AD, Ofek-Shlomai A, Vardy DA, et al. Depression in dermatological patients identified by the Mini International Neuropsychiatric Interview questionnaire. J Am Acad Dermatol. 2006 Jan;54(1):94-9.
- Dowlatshahi EA, Wakkee M, Arends LR, et al. The prevalence and odds of depressive symptoms and clinical depression in psoriasis patients: a systematic review and meta-analysis. J Invest Dermatol. 2014 Jun;134(6):1542-51.
- Bashir K, Dar NR, Rao SU. Depression in adult dermatology outpatients. J Coll Physicians Surg Pak. 2010 Dec;20(12):811-3.
- Gupta MA, Gupta AK, Schork NJ, et al. Depression modulates pruritus perception: a study of pruritus in psoriasis, atopic dermatitis, and chronic idiopathic urticaria. Psychosom Med. 1994 Jan-Feb;56(1):36-40.
- Fardet L, Petersen I, Nazareth I. Suicidal behavior and severe neuropsychiatric disorders following glucocorticoid therapy in primary care. Am J Psychiatry. 2012 May;169(5):491-7.
- Sundström A, Alfredsson L, Sjölin-Forsberg G, et al. Association of suicide attempts with acne and treatment with isotretinoin: retrospective Swedish cohort study. BMJ. 2010 Nov 11;341:c5812.
- Wakkee M, Nijsten T. Comorbidities in dermatology. Dermatol Clin. 2009 Apr;27(2):137-47.
- Huynh M, Gupta R, Koo JY. Emotional stress as a trigger for inflammatory skin disorders. Semin Cutan Med Surg. 2013 Jun;32(2):68-72.
- Gieler U, Consoli SG, TomÃ¡s-Aragones L, et al. Self-inflicted lesions in dermatology: terminology and classification–a position paper from the European Society for Dermatology and Psychiatry (ESDaP). Acta Derm Venereol. 2013 Jan;93(1):4-12.
- Gupta MA, Gupta AK. Current concepts in psychodermatology. Curr Psychiatry Rep. 2014 Jun;16(6):449.
- Gupta R, Huynh M, Ginsburg IH. Body dysmorphic disorder. Semin Cutan Med Surg. 2013 Jun;32(2):78-82.
- Kestenbaum T. Obsessive-compulsive disorder in dermatology. Semin Cutan Med Surg. 2013 Jun;32(2):83-7.
- Odlaug BL, Grant JE. N-acetyl cysteine in the treatment of grooming disorders. J Clin Psychopharmacol. 2007 Apr;27(2):227-9.
- Lepping P, Russell I, Freudenmann RW. Antipsychotic treatment of primary delusional parasitosis: systematic review. Br J Psychiatry. 2007 Sep;191:198-205.
- Levin EC, Gieler U. Delusions of parasitosis. Semin Cutan Med Surg. 2013 Jun;32(2):73-7.
- Manschreck TC, Khan NL. Recent advances in the treatment of delusional disorder. Can J Psychiatry. 2006 Feb;51(2):114-9.
- Patel V, Koo JY. Delusions of parasitosis; suggested dialogue between dermatologist and patient. J Dermatolog Treat. 2015 Oct;26(5):456-60.
- Lewin AB, Wu MS, McGuire JF, et al. Cognitive behavior therapy for obsessivecompulsive and related disorders. Psychiatr Clin North Am. 2014 Sep;37(3):415-45.
- Fried RG. Nonpharmacologic treatments in psychodermatology. Dermatol Clin. 2002 Jan;20(1):177-85.
- Fried RG. Nonpharmacologic management of psychodermatologic conditions. Semin Cutan Med Surg. 2013 Jun;32(2):119-25.