Role of Patch Testing With Standard and Cosmetic Series in Patients With Facial Allergic Contact Dermatitis Associated With Everyday Cosmetic Products

Background: Facial allergic contact dermatitis (ACD) is a common dermatological presentation, with rising incidence attributed to increasing cosmetic use. Patch testing remains the gold standard for identifying causative allergens. This study aimed to identify the allergens responsible for facial ACD using the Indian Standard Series and Indian Cosmetic Series. Methods: A cross-sectional observational study was conducted on 30 patients aged 18-60 years with clinically diagnosed facial ACD attending the dermatology outpatient department of a tertiary care teaching hospital in Haryana, India. All patients underwent patch testing with 20 allergens of the Indian Standard Series and 32 allergens of the Indian Cosmetic Series, as per Contact and Occupational Dermatoses Forum of India (CODFI) recommendations. Readings were taken on Day 2 using International Contact Dermatitis Research Group (ICDRG) grading. Results: The mean age was 39.26 ± 18.41 years, with female predominance (n=18,60%). The 41-50-year age group was most affected (n=11,36.67%). Homemakers constituted the largest occupational group (n=11,36.67%). Hair dye was the most commonly implicated agent (n=14,46.67%). The forehead (n=14,46.67%) and cheeks (n=12,40%) were the most affected sites. Itching and hyperpigmentation were the commonest clinical patterns (n=19,63.33% each). Para-phenylenediamine was the most frequent allergen (n=21), followed by fragrance mix (n=11), cetrimide (n=9), nickel sulphate (n=7), and parthenium (n=7). Conclusion: Facial ACD has become common with the widespread use of cosmetic products. Patch testing plays a crucial role in confirming the diagnosis and identifying the specific allergens responsible for sensitization. Testing with both standard and cosmetic series increases the likelihood of detecting clinically relevant allergens that may be missed with standard series alone. Identification of the offending allergens enables individualized counseling regarding avoidance of culprit ingredients and selection of safer alternatives, thereby reducing recurrent episodes. Routine consideration of patch testing should therefore be encouraged in patients with persistent, recurrent, or treatment-resistant facial dermatitis with a suspected cosmetic etiology.