Agar dark spot sirf ek side par hai, toh clinically yeh Post-Inflammatory Hyperpigmentation (PIH) ka sign hai, melasma ka nahi. Dr. Shweta Virmani, MD Dermatology confirm karti hain ki melasma se face ke dono sides par symmetrically discolored patches hote hain. PIH irregularly wahi hota hai jahan koi trauma ya acne lesion hua ho. Deep dermal pigmentation ko clear karne ke liye 10% niacinamide ko sirf 4 weeks tak use karna kaafi nahi hai.
Fitzpatrick skin types III to V mein, jisme mostly Indian skin tones aate hain, melanin production bahut reactive hota hai. Ek 10% niacinamide serum melanosomes ka transfer melanocytes se keratinocytes tak rok kar kaam karta hai. Kyunki epidermal cellular turnover mein 28 se 40 days lagte hain, isliye 4 weeks mein clearance expect karna jaldbazi hai. Clinical data show karta hai ki significant pigmentation reduction ke liye 12 se 16 weeks tak consistent application zaroori hai.
StatPearls NCBI ke according, melasma mostly sun-exposed areas ko affect karta hai aur symmetric brown-to-gray macules ki tarah dikhta hai. Iske alawa, short-wavelength blue light se persistent pigmentation hota hai jo darker Indian skin phototypes mein bahut stubborn hota hai. Agar aapka spot strictly unilateral (ek side par) hai, toh yeh PIH hai. Melasma ke liye systemic management ki zaroorat hoti hai, jabki PIH ko localized inflammation target karke theek kiya ja sakta hai.
Unilateral PIH ko effectively treat karne ke liye, ek multi-pathway clinical protocol follow karein. Pehle, melanin transfer ko block karne ke liye din mein do baar 10% niacinamide lagana continue rakhein. Doosra, pigmented surface cells ko hatane ke liye week mein do raat 5-10% glycolic acid jaisa chemical exfoliant introduce karein. Finally, rozana broad-spectrum SPF 30 ya usse zyada lagayein, aur har 2 hours mein reapply karein, kyunki UV exposure pigmentation treatments ke asar ko bilkul khatam kar deta hai.
English version: https://thedermaco.com/blogs/faq/melasma-vs-pih-one-sided-dark-spot-niacinamide
