Efficacy of Roflumilast Foam, 0.3%, in Patients With Seborrheic Dermatitis: A Double-blind, Vehicle-Controlled Phase 2a Randomized Clinical Trial.

Importance: Current topical treatment options for seborrheic dermatitis are limited by efficacy and/or safety. Objective: To assess safety and efficacy of roflumilast foam, 0.3%, in adult patients with seborrheic dermatitis affecting the scalp, face, and/or trunk. Design, Setting, and Participants: This multicenter (24 sites in the US and Canada) phase 2a, parallel group, double-blind, vehicle-controlled clinical trial was conducted between November 12, 2019, and August 21, 2020. Participants were adult (aged ≥18 years) patients with a clinical diagnosis of seborrheic dermatitis for a 3-month or longer duration and Investigator Global Assessment (IGA) score of 3 or greater (at least moderate), affecting 20% or less body surface area, including scalp, face, trunk, and/or intertriginous areas. Data analysis was performed from September to October 2020. Interventions: Once-daily roflumilast foam, 0.3% (n = 154), or vehicle foam (n = 72) for 8 weeks. Main Outcomes and Measures: The main outcome was IGA success, defined as achievement of IGA score of clear or almost clear plus 2-grade improvement from baseline, at week 8. Secondary outcomes included IGA success at weeks 2 and 4; achievement of erythema score of 0 or 1 plus 2-grade improvement from baseline at weeks 2, 4, and 8; achievement of scaling score of 0 or 1 plus 2-grade improvement from baseline at weeks 2, 4, and 8; change in Worst Itch Numeric Rating Scale (WI-NRS) score from baseline; and WI-NRS success, defined as achievement of 4-point or greater WI-NRS score improvement in patients with baseline WI-NRS score of 4 or greater. Safety and tolerability were also assessed. Results: A total of 226 patients (mean [SD] age, 44.9 [16.8] years; 116 men, 110 women) were randomized to roflumilast foam (n = 154) or vehicle foam (n = 72). At week 8, 104 (73.8%) roflumilast-treated patients achieved IGA success compared with 27 (40.9%) in the vehicle group (P < .001). Roflumilast-treated patients had statistically significantly higher rates of IGA success vs vehicle at week 2, the first time point assessed. Mean (SD) reductions (improvements) on the WI-NRS at week 8 were 59.3% (52.5%) vs 36.6% (42.2%) in the roflumilast and vehicle groups, respectively (P < .001). Roflumilast was well tolerated, with the rate of adverse events similar to that of the vehicle foam. Conclusions and Relevance: The results from this phase 2a randomized clinical trial of once-daily roflumilast foam, 0.3%, demonstrated favorable efficacy, safety, and local tolerability in the treatment of erythema, scaling, and itch caused by seborrheic dermatitis, supporting further investigation as a nonsteroidal topical treatment. Trial Registration: ClinicalTrials.gov Identifier: NCT04091646.

Lanolin Allergic Reactions: North American Contact Dermatitis Group Experience, 2001 to 2018.

BACKGROUND: Lanolin is an important cause of allergic contact dermatitis. OBJECTIVES: The aims of this study were to describe the epidemiology of lanolin allergy and to assess trends in patch test reactions to lanolin over time. METHODS: This study used a retrospective analysis of patients patch tested with lanolin alcohol 30% or Amerchol L-101 50% in petrolatum by the North American Contact Dermatitis Group between 2001 and 2018 (n = 43,691). RESULTS: Overall, 1431 (3.3%) had a positive reaction, and 1238 (2.8%) were currently relevant. Prevalence of lanolin allergy was 4.63% between 2011 and 2018 (P < 0.0001). Most lanolin-allergic patients had + (52%) reactions; 18%, and 6% had ++ and +++ reactions, respectively. Common primary anatomic sites of dermatitis were the hands (20.7%), scattered/generalized distribution (19.6%), and face (17.0%). Allergic reactions to lanolin were more common in children (4.5%) than in adults (3.2%, P = 0.0018). Compared with nonallergic patients, lanolin-allergic patients were more likely to have history of eczema or hay fever, male sex, older than 40 years, or Black race (P < 0.05). Common lanolin sources were personal care products and drugs/medications. Only 2.24% of the positive reactions were linked to occupation. CONCLUSIONS: Lanolin sensitivity was common. Reactions were often clinically relevant and linked to personal care products and medications.

Prevalence and trend of allergen sensitization in patients with a diagnosis of stasis dermatitis referred for patch testing, North American contact dermatitis group data, 2001-2016.

BACKGROUND: Few studies explored the relationship between stasis dermatitis (SD) and allergic contact dermatitis (ACD). OBJECTIVE: To examine trends, associations, and clinical relevance of ACD in patients referred for patch testing who had a final SD diagnosis. METHODS: Retrospective analysis from 2001 to 2016 of 38,723 patients from the North American Contact Dermatitis Group. RESULTS: After patch testing, 303 (0.7%) patients were diagnosed with SD; 46.7% had a concomitant diagnosis of ACD. Patients with vs. without a final SD diagnosis had similar proportions of ≥ 1 positive allergic reaction (59.7% vs. 64.7%; Chi-square, P = 0.0724) but higher odds of allergic reactions to fragrance mix I, bacitracin, quaternium-15, Myroxylon pereirae, benzalkonium chloride, ethyleneurea melamine formaldehyde, diazolidinyl urea, and propylene glycol. The most commonly relevant allergens in patients with final SD diagnosis were fragrance mix I, Myroxylon pereirae, bacitracin, quaternium-15, and formaldehyde. The most common allergen sources were personal care products, topical medications and other health aid products. CONCLUSION: Nearly half of patients with a final SD diagnosis were also diagnosed with ACD, supporting the role of patch testing in select SD patients.

Age-related differences in patch testing results among children: Analysis of North American Contact Dermatitis Group Data, 2001-2018.

BACKGROUND: An updated understanding of allergic contact dermatitis is needed, particularly in children. OBJECTIVES: To compare positive and clinically relevant reactions in children versus adults referred for patch testing. METHODS: Retrospective analysis of 1871 children and 41,699 adults from the North American Contact Dermatitis Group (NACDG) from 2001-2018. RESULTS: Both final diagnosis of allergic contact dermatitis (55.2% versus 57.3%; chi square, P = .0716) and prevalence of ≥ 1 currently relevant reaction to a NACDG screening allergen (49.2% vs 52.2%; P = .1178) were similar between children and adults. Currently in children, the most common relevant allergens were nickel sulfate (17.3%), hydroperoxides of linalool (7.8%), methylisothiazolinone (7.7%), cobalt chloride (7.0%), and fragrance mix I (4.9%). Approximately a fifth of children had a positive reaction to a non-NACDG allergen. CONCLUSION: Over half of children referred for patch testing were diagnosed with allergic contact dermatitis. The most common relevant allergens in children were nickel sulfate, cobalt chloride, and hydroperoxides of linalool. Twenty percent of children had at least 1 positive reaction to allergens/substances not on the NACDG screening series, underscoring the need for comprehensive testing.

Prevalence and trend of allergen sensitization in patients referred for patch testing with a final diagnosis of psoriasis: North American Contact Dermatitis Group data, 2001-2016.

BACKGROUND: Little is known about the relationship between psoriasis and allergic contact dermatitis (ACD). OBJECTIVE: To examine the associations with ACD, related clinical characteristics, and common positive and clinically relevant allergens of patients with a final diagnosis of psoriasis who were referred for patch testing. METHODS: Retrospective analysis of 38 723 patients from the North American Contact Dermatitis Group. RESULTS: Patients with a final diagnosis of psoriasis had lower proportions of ACD than those without psoriasis (32.7% vs 57.8%). In multivariable logistic regression models, psoriasis was inversely associated with female sex, Black or Asian race, and history of atopic dermatitis and hay fever. Patients with a final diagnosis of psoriasis were less likely to have one or more positive allergic patch-test reactions or to have a current clinically relevant patch-test reaction to the majority of the most commonly positive and/or relevant allergens. The most clinically relevant allergens included nickel sulfate, methylisothiazolinone, and fragrance mix I. CONCLUSION: Approximately one-third of patients who were referred for patch testing with a final diagnosis of psoriasis were also diagnosed with ACD. In select patients with suspected psoriasis who also have a clinical presentation suggestive of ACD, patch testing may be helpful.

Localized Bullous Pemphigoid Following Orthopedic Surgery.

Bullous pemphigoid is an autoimmune condition whereby the immune system forms antibodies that target the skin, resulting in the formation of blisters in a generalized and symmetric pattern. Localized bullous pemphigoid can occur in special circumstances. Here, we describe two patients that developed localized bullous pemphigoid in one lower extremity following orthopedic surgery. We propose that underlying edema following orthopedic surgery is a potential trigger for localized bullous pemphigoid.

Prevalence and Trend of Allergen Sensitization in Adults and Children with Atopic Dermatitis Referred for Patch Testing, North American Contact Dermatitis Group Data, 2001-2016.

BACKGROUND: The association between atopic dermatitis (AD) and allergic contact dermatitis (ACD) is controversial. OBJECTIVE: To analyze the prevalence, reaction strength, and trends of the most commonly positive and relevant allergens in patients with AD referred for patch testing. METHODS: This was a retrospective analysis of 38,482 patients from the North American Contact Dermatitis Group, 2001 to 2016. RESULTS: Most adults (56.0%) and children (52.8%) with a history of AD had a final diagnosis of ACD. Adults (66.5% vs 65.6%; χ2, P = .1459) and children (61.4% vs 62.3%, P = .7074) with or without a history of AD had similar proportions of one or more allergic patch test reactions. Adults with a history of AD had a greater number of allergic patch test positive reactions than those without it (2.0 ± 2.4 vs 1.9 ± 2.3; t test, P < .0001), whereas children did not (1.5 ± 1.8 vs 1.4 ± 1.6; P = .3839). Nickel sulfate, methylisothiazolinone, formaldehyde, fragrance mix I, sodium gold thiosulfate, and thimerosal were the most common allergens in adults and children with a history of AD. In multivariable logistic regression models, adults with versus without a history of AD had increased odds of reacting to 10 of the top 25 North American Contact Dermatitis Group screening allergens. Most allergens had similar strengths of reaction in adults or children with and without a history of AD or a current AD diagnosis; cobalt, fragrance mix I, and propylene glycol had weaker reactions. In multivariable logistic regression, adults with versus without an AD history had increased odds of relevance for 10 of the 25 most currently relevant allergens, whereas children with an AD history did not have increased relevance for any specific allergens. CONCLUSIONS: Most patients referred for patch testing with AD history had a final diagnosis of ACD. Patients with AD history had a similar likelihood of having a positive patch test reaction as those without an AD history. Adults with an AD history had a higher number of positive patch test reactions.

Prevalence and trend of allergen sensitization in patients with nummular (discoid) eczema referred for patch testing: North American Contact Dermatitis Group data, 2001-2016.

BACKGROUND: Few studies have examined the relationship between nummular (discoid) eczema (NE) and allergic contact dermatitis (ACD). OBJECTIVE: To examine trends, associations, and clinical relevance of ACD in patients with NE who were referred for patch testing. METHODS: Retrospective analysis of 38 723 patients from the North American Contact Dermatitis Group. RESULTS: Overall, 748 patients (1.9%) were diagnosed with NE; 23.9% had a concomitant diagnosis of ACD. The prevalence of NE fluctuated over time between 2001 and 2016, with no overall change in prevalence in diagnosed NE. In multivariable logistic regression models, NE increased steadily with age and was associated with male sex and Asian and other race/ethnicity, and inversely associated with a history of atopic dermatitis (AD) and hay fever. Patients with NE had lower proportions of one or more positive allergic reactions and lower odds of a positive reaction in multiple individual allergens. The most commonly relevant allergens in patients with NE were formaldehyde 2.0% aq., methylisothiazolinone, quaternium 15, fragrance mix I, and propylene glycol. CONCLUSION: NE is a heterogeneous disorder with distinct subsets of lesional distributions and a profile of relevant allergens, especially formaldehyde and formaldehyde releasers. Nearly one in four patients with NE had ACD, supporting the role of patch testing in patients with NE.

Contact dermatitis associated with preservatives: Retrospective analysis of North American Contact Dermatitis Group data, 1994 through 2016.

BACKGROUND: Preservatives are often necessary components of commercial products. Large-scale North American studies on preservative allergy are limited. OBJECTIVE: To evaluate demographics, positive patch test reactions (PPTRs), clinical relevance, and trends for preservatives tested by the North American Contact Dermatitis Group. METHODS: We conducted a retrospective cross-sectional analysis of North American Contact Dermatitis Group patch testing results of preservatives from 1994 through 2016. RESULTS: A total of 50,799 patients were tested; 11,338 (22.3%) had a PPTR to at least 1 preservative. The most frequent reactions were to methylisothiazolinone 0.2% aqueous (aq) (12.2%), formaldehyde 2% aq (7.8%), formaldehyde 1% aq (7.8%), quaternium-15 2% petrolatum (pet) (7.7%), and methyldibromo glutaronitrile/phenoxyethanol 2% pet (5.1%). Paraben mix 12% pet (1%), iodopropynyl butylcarbamate 0.1% pet (0.4%), benzyl alcohol 1% pet (0.3%), and phenoxyethanol 1% pet (0.2%) had the lowest PPTRs. Linear regression analysis of preservatives tested showed that only methylchloroisothiazolinone/methylisothiazolinone 0.01% aq (parameter estimate, 0.42; 95% CI, 0.17-0.66; P < .005) had a significant increase in PPTRs over time. LIMITATIONS: Collected variables are dependent on clinical judgment. Results may be prone to referral selection bias. CONCLUSIONS: This large North American study provides insight on preservative PPTRs and trends from 1994 through 2016.

Hand dermatitis in adults referred for patch testing: Analysis of North American Contact Dermatitis Group Data, 2000 to 2016.

BACKGROUND: Hand eczema (HE) is a heterogeneous and burdensome disorder. OBJECTIVE: To characterize the clinical characteristics, etiologies and allergen relevance in adults with HE referred for patch testing. METHODS: Retrospective analysis (2000-2016) of North American Contact Dermatitis Group data (n = 37,113). RESULTS: Overall, 10,034 patients had HE, with differences of overlap between allergic contact, irritant contact, and atopic dermatitis. Allergic contact HE fluctuated, whereas atopic HE steadily increased, and irritant HE decreased over time. HE was associated with higher proportions of positive patch tests (67.5% vs 63.8%; χ2, P < .0001). The five most common clinically relevant allergens were methylisothiazolinone, nickel, formaldehyde, quaternium-15, and fragrance mix I. HE was associated with significantly higher odds of positive patch test reactions and clinical relevance in 13 and 16 of the 25 most common allergens, respectively, including preservatives, metals, topical medications, and rubber accelerators. LIMITATIONS: No data on HE phenotype. CONCLUSION: HE in adults was associated with higher proportions of positive patch tests, with a heterogeneous profile of allergens. Patch testing remains an important tool in the evaluation of patients with HE.

Eyelid dermatitis in patients referred for patch testing: Retrospective analysis of North American Contact Dermatitis Group data, 1994-2016.

BACKGROUND: Eyelid dermatitis is a common dermatologic complaint. OBJECTIVE: To characterize patients with eyelid dermatitis. METHODS: Retrospective analysis (1994-2016) of North American Contact Dermatitis Group data. RESULTS: Of 50,795 patients, 2332 (4.6%) had eyelid dermatitis only, whereas 1623 (3.2%) also had dermatitis of the eyelids and head or neck. Compared with patients without eyelid involvement (n = 26,130), groups with eyelid dermatitis only and dermatitis of the eyelid and head or neck were significantly more likely to be female, white, and older than 40 years, and to have a history of hay fever, atopic dermatitis, or both (P < .01). Final primary diagnoses included allergic contact dermatitis (eyelid dermatitis only: 43.4%; dermatitis of the eyelid and head or neck: 53.5%), irritant contact dermatitis (eyelid dermatitis only: 17.0%; dermatitis of the eyelid and head or neck: 9.8%), and atopic dermatitis (eyelid dermatitis only: 13.1%; dermatitis of the eyelid and head or neck: 13.8%). Top 5 currently relevant allergens included nickel sulfate (eyelid dermatitis only: 18.6%; dermatitis of the eyelid and head or neck: 22.5%), fragrance mix I (eyelid dermatitis only: 16.5%; dermatitis of the eyelid and head or neck: 18.3%), methylisothiazolinone (eyelid dermatitis only: 16.5%; dermatitis of the eyelid and head or neck: 17.7%), gold sodium thiosulfate (eyelid dermatitis only: 14.7%; dermatitis of the eyelid and head or neck: 11.4%), and balsam of Peru (eyelid dermatitis only: 11.9%; dermatitis of the eyelid and head or neck: 12.6%). Both eyelid-involvement groups were significantly more likely to react to gold sodium thiosulfate, carmine, shellac, dimethylaminopropylamine, oleamidopropyl dimethylamine, and thimerosal (P < .05) compared with the no eyelid involvement group. LIMITATIONS: Lack of specific distribution patterns of eyelid dermatitis and no long-term follow-up data. CONCLUSION: Patch testing remains a critical tool in evaluating patients with eyelid dermatitis.

Patch Testing to Diphenylguanidine by the North American Contact Dermatitis Group (2013-2016).

BACKGROUND/OBJECTIVES: Carba mix (CM, 3% petrolatum) contains 1,3-diphenylguanidine (DPG, 1%), zinc diethyldithiocarbamate (1%), and zinc dibutyldithiocarbamate (1%). Because DPG is a component of CM, DPG is often not tested separately. The purpose of this study was to determine the frequency of concomitant reactions to CM and DPG. METHODS: A retrospective analysis of the 2013-2016 North American Contact Dermatitis Group data was conducted. The study group consisted of patients with final interpretation of "allergic" to either DPG or CM. Reactions coded as irritant or doubtful/macular erythema (+/- and not interpreted as allergic) were excluded. RESULTS: A total of 10,457 patients were patch tested to both CM and DPG, and 610 (5.8%) had allergic reactions to either CM or DPG (CM only [n = 292, 47.9%], DPG only [n = 190, 31.1%], both [n = 128, 21.0%]). A total of 39.4% of CM-allergic patients reacted to DPG, and 59.7% of DPG-allergic patients reacted to CM. Analyses found that 25% (++/+++ subgroup) to 40% (all patients) of allergic reactions to DPG would have been missed by testing to CM alone. More than 70% of reactions to CM and DPG were +/- or +. CONCLUSIONS: Patch testing to CM will miss 25% to 40% of positive reactions to DPG. Both CM and DPG have a high frequency of +/- and + reactions.

Contact Dermatitis Associated With Nail Care Products: Retrospective Analysis of North American Contact Dermatitis Group Data, 2001-2016.

BACKGROUND: Ingredients in nail care products may lead to allergic and/or irritant contact dermatitis. OBJECTIVE: The aims of this study were to determine frequency of contact dermatitis associated with nail care products, characterize associated body sites, and describe causative allergens. METHODS: A retrospective analysis was conducted with the North American Contact Dermatitis Group data between 2001 and 2016. RESULTS: Of the 38,775 patients tested, 769 (2.0%) had: 1) more than 1 allergic patch test reaction associated with a nail care product (n = 746), 2) irritant contact dermatitis associated with a nail care product (n = 14), or 3) both (n = 9). Primary body sites included the face (43.0%) and hands (27.6%). The top 5 allergens were (2-hydroxyethyl methacrylate (273/482, 56.6%), methyl methacrylate (210/755, 27.8%), ethyl acrylate (190/755, 25.2%), ethyl-2-cyanoacrylate (12/175, 6.9%) and tosylamide (273/755, 36.2%). Frequency of allergy to 2-hydroxyethyl methacrylate (P = 0.0069) and ethyl acrylate (P = 0.0024) significantly increased over the study period, whereas allergy secondary to tosylamide significantly decreased (P < 0.0001). CONCLUSIONS: As long-lasting nail techniques become widespread, the prevalence of contact dermatitis to nail care products is expected to increase. Almost one-fifth of nail care product-associated allergens would have been missed without additional screening allergens beyond the North American Contact Dermatitis Group series, underscoring the need for testing to a broad array of allergens.

Evaluation of the Relative Mildness of Commercial Sensitive Skin and Baby Laundry Detergents.

Laundry detergents that are free of fragrances and dyes should be recommended to patients with sensitive skin. To ensure mildness of these products, manufacturers typically conduct patch testing. A new method, which is more discerning than patch testing, called Detergent Mildness Index (DMI), has been described previously. Using the DMI method, 12 sensitive skin/baby laundry detergents, representing the top 85% of the marketplace, were evaluated. The product "all Free Clear®" was found to be the mildest liquid laundry detergent.

Evaluation of Patch Test Findings in Patients With Anogenital Dermatitis.

Importance: Contact dermatitis in the anogenital area is associated with sleep disturbance and dyspareunia and can profoundly affect quality of life. The literature on anogenital contact dermatitis and culprit allergens is limited. The last large-scale study on common, relevant allergens in patients with anogenital dermatitis was published in 2008. Objectives: To characterize patients with anogenital dermatitis referred for patch testing by the North American Contact Dermatitis Group, to identify common allergens, and to explore sex-associated differences between anogenital dermatitis and allergens. Design, Setting, and Participants: A retrospective, cross-sectional analysis was conducted of the North American Contact Dermatitis Group database among 28 481 patients who underwent patch testing from January 1, 2005, to December 31, 2016, at outpatient referral clinics in the United States and Canada. Exposure: Patch testing for allergens. Main Outcomes and Measures: Currently relevant allergic patch test reactions in patients with anogenital dermatitis. Results: Of 28 481 patients tested during the study period, 832 patients (336 men and 496 women; mean [SD] age, 50.1 [26.5] years) had anogenital involvement and 449 patients (177 men and 272 women; mean [SD] age, 49.6 [17.4] years) had anogenital dermatitis only. Compared with those without anogenital involvement, there were significantly more male patients in the group with anogenital dermatitis (177 [39.4%] vs 8857 of 27 649 [32.0%]; relative risk, 1.37; 95% CI, 1.14-1.66; P < .001). In the group with anogenital involvement, female patients were significantly less likely than male patients to have allergic contact dermatitis as a final diagnosis (130 [47.8%] vs 107 [60.5%]; relative risk, 0.78; 95% CI, 0.64-0.94; P = .01), whereas a final diagnosis of other dermatoses (eg, lichen planus, lichen sclerosus, or lichen simplex chronicus) was more frequent for female patients than for male patients (67 [24.6%] vs 28 [15.8%]; relative risk, 1.54; 95% CI, 1.02-2.31; P = .03). Of the 449 patients in the group with anogenital involvement only, 227 (50.6%) had 1 or more relevant reaction with patch testing. Allergens that were statistically significantly more common in patients with anogenital involvement compared with those without anogenital involvement included medicaments such as dibucaine (10 of 250 patients tested [4.0%] vs 32 of 17 494 patients tested [0.2%]; relative risk, 22.74; 95% CI, 11.05-46.78; P < .001) and preservatives such as methylchloroisothiazolinone and methylisothiazolinone (30 of 449 patients tested [6.7%] vs 1143 of 27 599 patients tested [4.1%]; relative risk, 1.61; 95% CI, 1.14-2.41; P = .008). A total of 152 patients met the definition for anogenital allergic contact dermatitis, which is defined as anogenital involvement only, allergic contact dermatitis as the only diagnosis, and 1 or more positive reaction of current clinical relevance. Conclusions and Relevance: For patients with anogenital involvement only who were referred for patch testing, male patients were more likely to have allergic contact dermatitis, whereas female patients were more likely to have other dermatoses. Common allergens or sources consisted of those likely to contact the anogenital area. For individuals with anogenital involvement suspected of having allergic contact dermatitis, reactions to preservatives, fragrances, medications (particularly topical anesthetics), and topical corticosteroids should be tested.

Facial Dermatitis in Male Patients Referred for Patch Testing: Retrospective Analysis of North American Contact Dermatitis Group Data, 1994 to 2016.

Importance: Facial dermatitis in women is well characterized. However, recent shifts in the men's grooming industry may have important implications for male facial dermatitis. Objective: To characterize male patients with facial dermatitis. Design, Setting, and Participants: A 22-year retrospective cross-sectional analysis (1994-2016) of North American Contact Dermatitis Group (NACDG) data, including 50 507 patients who underwent patch testing by a group of dermatology board-certified patch test experts at multiple centers was carried out. Facial dermatitis was defined as involvement of the eyes, eyelids, lips, nose, or face (not otherwise specified). Main Outcomes and Measures: The main outcome was to compare characteristics (including demographics and allergens) between male patients with facial dermatitis (MFD) and those without facial dermatitis (MNoFD) using statistical analysis (relative risk, CIs). Secondary outcomes included sources of allergic and irritant contact dermatitis and, for occupationally related cases, specific occupations and industries in MFD. Results: Overall, 1332 male patients (8.0%) were included in the MFD group and 13 732 male patients (82.0%) were included in MNoFD. The mean (SD) age of participants was 47 (17.2) years in the MFD group and 50 (17.6) years in the MNoFD group. The most common facial sites were face (not otherwise specified, 817 [48.9%]), eyelids (392 [23.5%]), and lips (210 [12.6%]). Participants in the MFD group were significantly younger than MNoFD (mean age, 47 vs 50 years; P < .001). Those in the MFD group were less likely to be white (relative risk [RR], 0.92; 95% CI, -0.90 to 0.95) or have occupationally related skin disease (RR, 0.49; 95% CI, -0.42 to 0.58; P < .001) than MNoFD. The most common allergens that were associated with clinically relevant reactions among MFD included methylisothiazolinone (n = 113; 9.9%), fragrance mix I (n = 27; 8.5%), and balsam of Peru (n = 90; 6.8%). Compared with MNoFD, MFD were more likely to react to use of dimethylaminopropylamine (RR, 2.49; 95% CI, -1.42 to 4.37]) and paraphenylenediamine (RR, 1.43; 95% CI, -1.00 to 2.04; P < .001). Overall, 60.5% of NACDG allergen sources were personal care products. Conclusions and Relevance: Although many allergens were similar in both groups, MFD were more likely to react to use of dimethylaminopropylamine and paraphenylenediamine, presumably owing to their higher prevalence in hair products. Most sources of allergic and irritant contact dermatitis in MFD were personal care products. This study provides insight into the risks and exposures of the increasing number of grooming products used by male dermatology patients. This will enable clinicians to better identify male patients who would benefit from patch testing and treat those with facial dermatitis.