Medication Summary
Medications used in the treatment of dermatitis artefacta and associated conditions include the following:
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and oral antimicrobials
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Antidepressants (selective serotonin reuptake inhibitors [SSRIs] and tricyclic antidepressants [TCAs])
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Antipsychotic agents (typical and atypical)
Antimicrobials, Topical
Class Summary
Topical antimicrobials are used to treat the localized skin infections that often accompany self-inflicted lesions.
Neomycin/polymyxin B/bacitracin topical (Neo-Polycin, Neosporin)
Neomycin is used for treatment of minor infections; it inhibits bacterial protein synthesis and growth. Polymyxin B disrupts the bacterial cytoplasmic membrane, permitting leakage of intracellular constituents and causing inhibition of bacterial growth. Bacitracin prevents transfer of mucopeptides into the growing cell wall, thereby inhibiting bacterial growth.
Fusidic acid
Fusidic acid is a topical antibacterial that inhibits bacterial protein synthesis, causing bacterial death.
Antibiotics
Class Summary
Oral antibiotics are given to treat impetiginized skin lesions.
Cephalexin (Keflex)
Cephalexin is a first-generation cephalosporin that inhibits bacterial replication by inhibiting bacterial cell-wall synthesis. It is bactericidal and effective against rapidly growing organisms forming cell walls. Resistance occurs through alteration of penicillin-binding proteins.
Cephalexin is effective for treatment of infections caused by streptococci or staphylococci, including penicillinase-producing staphylococci; it may be used to initiate therapy when such infections are suspected. It is given orally when outpatient management is indicated. Cephalexin is recommended for impetigo caused by Staphylococcus aureus resistant to erythromycin. Its primary activity is against skin flora. It is used for treatment of skin infections or for prophylaxis in minor procedures.
Erythromycin (E.E.C. 400, PCE, Ery-Tab)
Erythromycin is used to treat staphylococcal and streptococcal infections in patients with hypersensitivity or with a contraindication to penicillin or cephalexin. It may result in gastrointestinal (GI) upset, in which case prescription of an alternative macrolide or a change to 3-times-daily dosing is advisable. Erythromycin covers most potential etiologic agents, including Mycoplasma spp; it is less active against Haemophilus influenzae.
Erythromycin inhibits bacterial growth, possibly by blocking dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest. It has the added advantage of being a good anti-inflammatory agent by virtue of its ability to inhibit migration of polymorphonuclear leukocytes.
Although a 10-day treatment course seems to be standard, treating until the patient has been afebrile for 3-5 days seems to be more rational. In children, age, weight, and severity of infection determine the proper dosage. When twice-daily dosing is desired, half of the total daily dose may be taken every 12 hours. For more severe infections, the dose should be doubled.
Antidepressants, SSRIs
Class Summary
SSRIs (including paroxetine, citalopram, and sertraline as well as fluoxetine) are first-line therapy for depression. For dermatitis artefacta associated with obsessive-compulsive disorder, use of an SSRI for at least 6 months to 1 year, in conjunction with psychotherapy, is recommended. Choice of an agent depends on adverse effects and drug interactions. Adverse effects of SSRIs seem to be idiosyncratic; thus, if dosing is started at a conservative level and advanced as tolerated, relatively few reasons exist to recommend one SSRI over another.
Fluoxetine (Prozac)
Fluoxetine selectively inhibits presynaptic serotonin reuptake, with minimal or no effect on reuptake of norepinephrine or dopamine. Because it may cause more adverse GI effects than other SSRIs currently available, it is not recommended as a first choice. It may be given as a liquid or as a capsule, in a single dose or divided doses. The presence of food does not appreciably alter medication levels.
Because of the long half-life (72 hours), it may take as long as 4-6 weeks to achieve steady-state levels. The long half-life is both an advantage and a drawback. If the drug works well, an occasional missed dose is not a problem; if problems occur, eliminating all active metabolites takes a long time.
Sertraline (Zoloft)
Sertraline selectively inhibits presynaptic serotonin reuptake, with minimal or no effect on reuptake of norepinephrine or dopamine.
Paroxetine (Paxil, Pexeva)
Paroxetine is a potent selective inhibitor of neuronal serotonin reuptake. It also has a weak effect on norepinephrine and dopamine neuronal reuptake. For maintenance, the dosing should be adjusted so as to maintain the patient on the lowest effective dosage, and the patient should be periodically reassessed to determine the need for continued treatment.
Fluvoxamine (Luvox CR)
Fluvoxamine enhances serotonin activity through selective reuptake inhibition at the neuronal membrane. It does not significantly bind to alpha-adrenergic, histamine, or cholinergic receptors and thus has fewer adverse effects than TCAs. Fluvoxamine has been shown to reduce repetitive thoughts, maladaptive behaviors, and aggression and to increase social relatedness and language use.
Citalopram (Celexa)
Citalopram enhances serotonin activity through selective reuptake inhibition at the neuronal membrane. No head-to-head comparisons of SSRIs have been done; however, on the basis of metabolism and adverse effects, citalopram is considered the SSRI of choice for patients with head injury.
Escitalopram (Lexapro)
Escitalopram is an SSRI and an S-enantiomer of citalopram. It is used for the treatment of depression. Its mechanism of action is thought to be potentiation of serotonergic activity in the CNS, resulting from inhibition of CNS neuronal reuptake of serotonin. The onset of depression relief may be obtained after 1-2 weeks—sooner than is possible with other antidepressants.
Antidepressants, TCAs
Class Summary
TCAs are used to treat the underlying psychiatric disorder in patients with dermatitis artefacta.
Doxepin
Doxepin has antihistamine, antipruritic, and antidepressant properties. It may be effective in patients with depression (with agitation) and a primary symptom of pruritus. Doxepin increases concentrations of serotonin and norepinephrine in the central nervous system (CNS) by inhibiting their reuptake by the presynaptic neuronal membrane; such inhibition is associated with a decrease in symptoms of depression.
Amitriptyline
Amitriptyline may be effective for depression with primary symptoms of pain sensations (eg, burning, chafing, or stinging). Analgesia can usually be achieved with doses lower than 50 mg given at bedtime. Amitriptyline inhibits reuptake of serotonin or norepinephrine at the presynaptic neuronal membrane, thereby increasing CNS concentrations. It may increase or prolong neuronal activity; reuptake of these biogenic amines is important physiologically in terminating transmitting activity.
Clomipramine (Anafranil)
Clomipramine is a dibenzazepine compound belonging to the TCA family. It affects serotonin uptake, and its metabolite, desmethylclomipramine, affects norepinephrine uptake.
Nortriptyline (Pamelor)
Nortriptyline has demonstrated effectiveness in the treatment of chronic pain. It may inhibit the reuptake of serotonin and/or norepinephrine by the presynaptic neuronal membrane, which, in turn, increases their synaptic concentration in the CNS.
Desipramine (Norpramin)
This is the original TCA used for depression. These agents have been suggested to act by inhibiting reuptake of noradrenaline at synapses in central descending pain modulating pathways located in the brainstem and spinal cord.
Antipsychotics, 1st Generation
Class Summary
Typical antipsychotics are used to treat the underlying psychiatric disorder in patients with dermatitis artefacta.
Pimozide (Orap)
Pimozide is a centrally acting dopamine-receptor antagonist that has been shown to be effective for delusions of parasitosis. It is available in a 2-mg scored tablet in the United States; 2-, 4-, and 10-mg tablets are available in Canada. Clinical response usually occurs within 10-14 days.
Antipsychotics 2nd Generation
Class Summary
Atypical antipsychotics carry a lower risk of extrapyramidal adverse effects than typical antipsychotics.
Risperidone (Risperdal)
Risperidone has been shown to be effective for delusions of parasitosis. It binds to dopamine D2 receptors with 20-times lower affinity than that for serotonin 5-HT2 receptors. Risperidone alleviates negative symptoms of psychoses and reduces the prevalence of extrapyramidal adverse effects. It is indicated for treatment of psychotic disorders, including schizophrenia and bipolar disorder. Clinical response usually occurs within 10-14 days.
Iloperidone (Fanapt)
Iloperidone is an atypical antipsychotic agent indicated for acute treatment of schizophrenia. Its precise mechanism of action is unknown. It antagonizes D2 and 5-HT2 receptors. However, it shows high affinity for 5-HT2A, D2, and D3 receptors and low-to-moderate affinity for D1, D4, H1, 5-HT1A, 5HT6, 5-HT7, and NE alpha1 receptors.
Paliperidone (Invega)
Paliperidone is the active metabolite of risperidone. Its therapeutic effects consist of mixed central serotonergic and dopaminergic antagonism. Unlike risperidone, paliperidone exhibits 10-fold lower affinity for alpha-2 and 5-HT2A receptors and almost 3- to 5-fold lower affinity for 5-HT1A and 5HT1D, respectively.
Olanzapine (Zyprexa)
Olanzapine may inhibit serotonin, muscarinic, and dopamine effects. Its efficacy is comparable to that of risperidone; it has fewer dose-dependent adverse effects but is associated with more concern about weight gain.
Quetiapine (Seroquel)
Quetiapine may act by antagonizing dopamine and serotonin effects. Its efficacy is comparable to those of risperidone and olanzapine; it has fewer dose-dependent adverse effects and is associated with less concern about weight gain.
