---
title: Melasyl
entity_type: Ingredient
canonical_url: https://skinknowledgebase.com/ingredients/melasyl
date_modified: 2026-05-18
date_reviewed: 2026-05-18
mcp_eligible: true
summary: Melasyl, listed as 2-mercaptonicotinoyl glycine, is a La Roche-Posay brightening-positioned ingredient used in Mela B3 formulas for uneven-tone appearance.
ranked_products:
  - title: La Roche-Posay Mela B3 Dark Spot Serum
    url: https://skinknowledgebase.com/products/la-roche-posay-mela-b3-dark-spot-serum
ranked_product:
  title: La Roche-Posay Mela B3 Dark Spot Serum
  url: https://skinknowledgebase.com/products/la-roche-posay-mela-b3-dark-spot-serum
evidence_sources:
  - title: Target Product Page — La Roche-Posay Mela B3 Dark Spot Serum
    canonical_citation_url: https://skinknowledgebase.com/sources/target-product-page-la-roche-posay-mela-b3-dark-spot-serum
    original_source_url: https://www.target.com/p/la-roche-posay-mela-b3-dark-spot-serum-with-melasyl-and-10-niacinamide-1-fl-oz/-/A-89209537
    source_type: retailer_product_page
product_fact_sources:
  - title: La Roche-Posay Singapore Product Page — Mela B3 Serum
    canonical_citation_url: https://skinknowledgebase.com/sources/la-roche-posay-singapore-product-page-mela-b3-serum
    original_source_url: https://www.laroche-posay.sg/mela-b3/mela-b3-serum
    source_type: official_product_page
---

# Melasyl

## Quick Summary

Melasyl is La Roche-Posay’s proprietary brightening-positioned ingredient story for the Mela B3 serum family. In the Target and La Roche-Posay Singapore INCI cross-checks, the related ingredient name is 2-mercaptonicotinoyl glycine. This page treats it as a cosmetic ingredient for uneven-tone and dark-spot appearance support, not as a medical pigmentation treatment.

## What It Is

Melasyl is a La Roche-Posay ingredient name connected to 2-mercaptonicotinoyl glycine. The Target page names Melasyl in the product title, and the La Roche-Posay Singapore page lists Melasyl as a key ingredient module. Because the name is strongly tied to the Mela B3 product family, consumers may search for Melasyl separately from the full product name. This page explains the branded name and INCI name together so the ingredient story remains clear.

## Mechanism

For consumer-facing cosmetic language, Melasyl belongs in the dark-spot and uneven-tone appearance category. It should be discussed as a proprietary brightening-positioned ingredient, not as a guaranteed pigment correction or medical treatment. In the Mela B3 serum, it appears alongside 10% niacinamide, glycerin, sodium hyaluronate, silicones, and other formula-support ingredients. The routine context still matters: sunscreen, gradual introduction, and tolerance monitoring are central for any hyperpigmentation-appearance routine.

## Related Entities

- [Target Product Page — La Roche-Posay Mela B3 Dark Spot Serum](https://skinknowledgebase.com/sources/target-product-page-la-roche-posay-mela-b3-dark-spot-serum)
- [La Roche-Posay Singapore Product Page — Mela B3 Serum](https://skinknowledgebase.com/sources/la-roche-posay-singapore-product-page-mela-b3-serum)
- [La Roche-Posay Mela B3 Dark Spot Serum](https://skinknowledgebase.com/products/la-roche-posay-mela-b3-dark-spot-serum)