Long established as the most effective ingredient for treating brown spots, hydroquinone works by gradually fading the appearance of dark spots resulting from sun exposure or other factors.

Over-the-counter hydroquinone products can contain 0.5% to 2% concentrations of hydroquinone; 4% (and sometimes higher) concentrations are available only from physicians.

Some concerns about hydroquinone’s safety on skin have been expressed, but despite the controversy, abundant research from reputable sources shows hydroquinone to be safe and effective. If you’re struggling with brown spots or skin discolourations, hydroquinone remains among the best ingredients to treat them.

A reminder that no ingredient will work to fade brown spots if you’re not diligent about daily application of a broad spectrum sunscreen. Unprotected sun exposure is the root cause of most dark spots, so forgoing sunscreen means you won’t see the results you want, no matter how well formulated the product may be.

References for this information:

The Journal of Clinical and Aesthetic Dermatology, August 2014, pages 13-17

Journal of Drugs in Dermatology, March 2013, pages S32-S37

The Journal of Dermatological Treatment, September 2010, pages 272-275

Journal of the American Academy of Dermatology, November 2007, pages 854-872

Dermatologic Therapy, September-October 2007, pages 308-313

Critical Reviews in Toxicology, October 2007, pages 887-914; and May 1999, pages 283-330

Journal of the European Academy of Dermatology and Venereology, August 2006, pages 781-787

Journal of Toxicology and Environmental Health, June 1998, pages 301-317

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About the Experts

Paula Begoun is the best-selling author of 20 books about skincare and makeup. She is known worldwide as The Cosmetics Cop and creator of Paula’s Choice Skincare. Paula’s expertise has led to hundreds of appearances on national and international radio, print, and television including:

The Paula's Choice Research Team is dedicated to busting beauty myths and providing expert advice that solves your skincare frustrations so you can have the best skin of your life!