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CYSTEAMINE

Description

Cysteamine is a potent antioxidant and skin-brightening agent gaining traction in advanced skincare formulations. This sulfur-containing compound, also known as β-mercaptoethylamine, is a metabolite of the amino acid cysteine and plays a crucial role in cellular functions. In skincare, cysteamine's primary mechanism of action involves inhibiting melanin production by interfering with key enzymes in the melanogenesis pathway.

Studies have shown cysteamine to be effective in reducing hyperpigmentation, melasma, and post-inflammatory hyperpigmentation. It offers a safer alternative to hydroquinone, with fewer side effects and a lower risk of paradoxical darkening. Cysteamine's antioxidant properties also contribute to overall skin health by neutralizing free radicals and supporting the skin's natural defense mechanisms.

Typically formulated at concentrations between 1% and 5%, cysteamine is most effective when used in leave-on products such as creams or serums. Due to its potential to cause initial irritation, it is often recommended for nighttime use and should be introduced gradually into a skincare routine. Cysteamine's efficacy can be enhanced when combined with other brightening agents like niacinamide or vitamin C.