Is This Popular Skin Ingredient Actually Dangerous?

Hydroquinone: It’s the go-to skin-care ingredient for lightening discoloration—acne scars, melasma, sunspots and the like. Dermatologists favor it because of its effectiveness, but many question its safety. We asked two experts to weigh in for both sides of the story.

The Pro

The best thing about hydroquinone is that it works. “It blocks an enzyme, tyrosinase, that allows for the transfer of pigment from pigment-producing cells to skin cells where pigment becomes visible,” says West Hollywood, CA, dermatologist Derek Jones, MD. “Hydroquinone cannot exceed 2 percent in over-the-counter products, which means it takes longer to see results,” says San Antonio dermatologist Vivian Bucay, MD. “Studies have shown that 4 percent prescription-strength hydroquinone is more effective.” It can take one to three months to see an improvement, and you may have to use salicylic acid, a retinoid or in-office peelsto get the effect you’re after.

You May Also Like: 3 Things About Natural Products You Shouldn't Believe

The Con

Hydroquinone has its advantages, but there is speculation that it is associated with rare health effects after long-term use. “The potential toxicity with hydroquinone has been associated with oral, not topical use,” says Dr. Jones. Another downside: how long you can use it for. “Hydroquinone is to be used for short periods of time only,” explains Dr. Bucay. Some people experience redness, burning and inflammation from using it, which may result in more pigment. Make sure you’re not overapplying it, which won’t lighten your skin any faster. “If you overdo it, although rare, it can create a halo effect, which is reversible upon discontinuation of the product,” says Dr. Jones.

The Bottom Line

Use a safe, doctor-approved formula, follow the instructions and stop using it at after three months (switch to arbutin, niacinamide or kojic acid to maintain your results). As long as you follow the proper protocol given to you, you should be in the clear.