About the Author
(Simon) Se Mang Wong, MD FRCPC Clinical Associate Professor Director of Undergraduate Education UBC Department of Dermatology and Skin Science Medical Director, Skin Health Liaison Clinic for Providence Health at Mount St. Joseph Hospital
Dr Wong completed his medical degree and his dermatology residency at the University of British Columbia. He currently practices in New Westminster, BC and is one of the visiting dermatology consultants for patients in Whitehorse, YK. Dr. Wong also practices at the psychodermatology clinic (SKIL Clinic – Skin Health Liaison Clinic) in the Mount Saint Joseph Ambulatory Clinic which is the only clinic of its kind in British Columbia and is a joint clinic run by dermatology and psychiatry.
Canadian Dermatology Today, Volume 1, Issue 4, November 2020
Skin picking: A practical approach for the busy dermatologist
There is often a sense of dread when a dermatologist receives a referral for skin picking or excoriations. Due to the nature of our practices, these referrals typically suggest a longer visit, a frustrated patient, and ultimately, a less-than-satisfying visit for all parties involved. How can this be minimized?
There are many reasons why a patient might manipulate their skin including an underlying dermatologic condition or neurologic abnormality, pruritus without a rash, medication or drug abuse, and psychiatric illness. As a practicing dermatologist, a patient who presents with an underlying dermatologic condition is relatively easy to identify and diagnose as these cases of skin picking are usually related to an underlying inflammatory dermatosis, infection, or infestation. Similarly, systemic illnesses leading to pruritus without a rash and underlying neurologic abnormality are equally easy to identify and diagnose. An important neurologic condition to rule out, which may lead to skin picking is dementia. The dermatologist should also be familiar with identifying medications and/or recreational drugs of abuse that may lead to itching and subsequent picking. This, then, leaves the category of psychiatric illnesses. Excoriation (skin picking) disorder is listed in the DSM-V as follows1:
For the practicing dermatologist, the above criteria can be difficult to remember. Instead, it may be easier to approach the patient according to the primary psychopathology: delusional, depressive, anxious, or obsessive-compulsive, which may help guide the management approach. It is important for the dermatologist to be reminded that one of the most important aspects to the successful management of these patients involves the building of rapport. Recognizing that there is no single “right” way, it is important to develop one’s own style of interacting with these patients. For example, empathic listening while the patient details their difficulties may be very therapeutic for many of these patients who can feel as though their concerns may not have always been previously heard. At the same time, it is important to remain neutral and avoid speculation pertaining to the potential underlying cause of the patient’s lesions.
A thorough physical examination is critical to ensuring an accurate diagnosis. All skin lesions should be reviewed, specifically looking for primary lesions suggesting an alternative diagnosis. Patients with delusions of parasitosis often display the “matchbox” or “baggy” sign containing collected samples, often containing keratinaceous debris or bits of dried blood. This is thought to be pathognomonic of this condition. However, it is important that the dermatologist actually review these samples to ensure there are not samples of arthropods that can actually cause a bite reaction, such as a bedbug.
Sometimes, a patient will bring in an insect that is thought to represent the culprit organism. If a specimen is sent off for identification, it is important to stipulate on the lab requisition that you are looking for an organism known to bite/infest humans.
As practices are busy, it is important to arrange short, but frequent visits for these patients. Although there may be a desire to refer these patients out for psychiatric assessment, it is critical to have an established relationship with mental health clinicians within your network. This is particularly important in delusional patients. The majority of our mental health colleagues have not seen these types of patients and their lesions and it is quite easy for unfamiliar mental health professionals to mistake the lesions as being infectious in nature. A single psychiatric assessment suggesting the lesions are “infected” can significantly delay the care some of these patients need.
The key to identifying a delusional patient is that they often articulate a firm belief that something is causing their lesions. Unfortunately, management of these patients is particularly challenging as they lack insight with respect to any underlying psychiatric condition.For patients who agree to a course of medication, antipsychotics are the recommended first-line treatments. Pimozide is a first-generation antipsychotic which has limited peer-reviewed data to support its use in patients with delusions of infestation, however, due to concerns with potential side effects, second generation antipsychotics are suggested.3 Risperidone and olanzapine are the most commonly prescribed second-generation antipsychotics for this condition with risperidone being favored over olanzapine given that the latter has greater documented risk of weight gain and metabolic syndrome.4 Aripiprazole, a newer third-generation antipsychotic, has also demonstrated some success in these patients as evidenced by several case reports supporting its use.5,6
Non-delusional patients are usually easier to identify and treat as they are able to provide significant insight as to the underlying cause of their lesions and they are also usually agreeable to treatment. These patients may often present with an overlap of various other psychiatric conditions such as depression with anxiety, anxiety with depression, depression and anxiety with obsessive-compulsive traits, obsessions and/or compulsions leading to depression and anxiety due to frustration, to name a few. These patients will often require combination treatment modalities.7 Clinicians should select a therapy that addresses the most prominent psychiatric symptom as a starting point. For example, antidepressants when depressive symptoms predominate, anxiolytics when anxiety symptoms predominate; and anti-obsessional and/or anti-compulsion agents for obsessive-compulsive symptoms. After a few weeks, depending on patient response, the addition of adjunctive agents may be warranted.
For patients with depression necessitating pharmacotherapy, selective serotonin reuptake inhibitors (SSRIs) are still recommended as first-line agents, however clinicians may also wish to consider noradrenaline and dopamine reuptake inhibitors (NDRIs) as an alternative first-line agent.8 These agents may also be used as anxiolytics. Clinicians should be mindful that since the time between initiation of therapy and optimal response may take some time with these classes of drugs, patients with significant anxiety issues may be candidates for benzodiazepines while bridging to these agents. SSRIs are very versatile agents and at higher doses, these agents may also be useful in patients with obsessive-compulsive disorders. At our combined psychiatry-dermatology clinic, however, we have found clomipramine, at lower, non-antidepressant dosages, to be very useful.9 This agent was the first drug used in the treatment of obsessive-compulsive disorders and is indicated for patients ten years of age and older.10
In summary, many patients present with excoriations to the dermatologist with the majority of these patients having an underlying dermatologic condition or systemic illness that can be identified as the trigger for their skin picking. Clinicians treating these patients should be reminded that medications and recreational drugs can also contribute to this problem. In order to help the busy clinician manage these rare patients who present with a psychiatric cause for their excoriation disorder, it is important to identify the major psychiatric symptom. Once that has been identified, a targeted therapy will allow for appropriate management of these patients and aid in ensuring an optimal outcome.
1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Arlington, VA: American Psychiatric Association; 2013 254-7.
2. Reich et al, Delusions of Parasitosis: An Update. Dermatol Ther (Heidelb) (2019) 9:631–638 https://doi.org/10.1007/s13555-019-00324-3
3. Hamann K, Avnstorp C. Delusions of infestation treated by pimozide: a double-blind crossover clinical study. Acta Derm Venereol. 1982; 62:55–8.
4. Freudenmann RW, Lepping P. Second-generation antipsychotics in primary and secondary delusional parasitosis. J Clin Psychopharmacol. 2008;28: 500–8.
5. Rocha FL, Hara C. Aripiprazole in delusional parasitosis: Case report. Prog Neuropsychopharmacol Biol Psychiatry. 2007 Apr 13;31(3):784-6. doi: 10.1016/j.pnpbp.2007.01.001.
6. Ladizinski, B et al. Aripiprazole as a viable alternative for treating delusions of parasitosis. J Drugs Dermatol. 2010 Dec; 9(12): 1531-2.
7. Tomas-Aragones, L et al. Self-Inflicted Lesions in Dermatology: A management and therapeutic approach – A position paper from the European Society for Dermatology and Psychiatry. Acta Derm Venereol 2017; 97: 159-172.
8. Kennedy, SH et al. Canadian Network for mood and anxiety treatments 2016 Clinical guidelines for the management of adults with major depressive disorder. Section 3. Can J Psychiatry 2016 Sep; 61(9): 540-560.
9. Del Casale, A et al. Psychopharmacological treatment of Obsessive–compulsive disorder (OCD). Curr Neuropharmacol. 2019; 17(8): 710-736.
10. Apotex, Inc. Apo-Clomipramine Product Monograph. Oct 31, 2018