Maintain Your Brown Skin Tone with Niacinamide, Glutathione, Alpha Arbutin, and More What Are the Side Effects of Hydroquinone 4%? Okdermo What is Hydroquinone? And Why is it controversial? , The gold standard for treating these darker patches was a topical skin lightening ingredient called hydroquinone, which works by reducing the 4 Key Steps for Dark Spots:, First and Foremost Sun Protection , The Bleaching Cream Hydroquinone , Retinoid Tretinoin or otherwise, Strong supporting cast. , Vitamin C, Kojic acid, Tranexamic acid,