Do cosmetics have a role in melasma? Preliminary results of a pilot study of patch testing in melasma

Abstract

Objectives: Melasma can be associated with pigmented contact dermatitis (PCD) that often goes unrecognized. The concept of cosmetic contact sensitivity in melasma is relatively less studied. In this era of overwhelming use of cosmetics among both men and women, the role of various cosmetic products in melasma and PCD needs to be extensively explored. Patch test in melasma patients can help recognize this cosmetic contact sensitivity in melasma patients. Thus, our study was to find the role of cosmetics in melasma patients. Material and Methods: A hospital-based, pilot study conducted in the Dermatology outpatient department of All India Institute of Medical Sciences, Rishikesh, Uttarakhand from January 2020 to February 2020. Seventeen consecutive patients with melasma were patch tested with Indian cosmetic series procured from the Systopic Pharmaceutical Ltd., standard set of commercial cosmetic products and patient products, if applicable. Day 3 and 5 readings were recorded. Results: Patch test was positive in 15 (88.2%) patients, with a relevance of 66.7%. Thiomersal was the most common allergen (53.3%) observed in our study population. Conclusion: Thiomersal in cosmetic products may be an important allergen to cause melasma.