Hydroquinone

What is hydroquinone and what is it used for?

Hydroquinone is a phenolic compound that suppresses tyrosinase, the enzyme involved in producing melanin, the pigment that gives skin its colour. It also occurs naturally in trace amounts in some plants, coffee and tea; but what is used in cosmetics and medicines is the pure, synthetic form. Because of this effect, it has been used for many years to fade melasma (the “mask of pregnancy”), sun spots and post-inflammatory marks.

Its effect is strong, so it is regarded as a substance that should be used at the right dose, for the right length of time and with sun protection, under a doctor's supervision.

Legal status: cosmetic or medicine?

Under the EU Cosmetics Regulation, hydroquinone is among the banned substances in cosmetic products. The only exception is that it is permitted at a very low level in artificial nail systems for professional use. Turkish cosmetics legislation is aligned with the EU.

For treating skin pigmentation, products containing hydroquinone may only be used as prescription medicines, on a doctor's advice. In the US, the FDA has also ended over-the-counter sales of hydroquinone skin lighteners.

What are the risks?

• Irritation and contact dermatitis: Redness, burning and itching are common side effects.
• Ochronosis: With long-term, uncontrolled use, a permanent blue-black discolouration of the skin can develop, especially in darker skin; it is difficult to treat.
• Rebound pigmentation: When use is stopped or the skin is not protected from the sun, dark spots can become more noticeable.
• Other harmful ingredients: Unregulated whitening creams have been reported to contain mercury compounds or strong corticosteroids not listed on the label.

Whitening creams bought online

Some “dark spot creams” or “whitening” products sold on foreign websites or through social media may contain high levels of hydroquinone despite the ban; sometimes there is no ingredient list at all, or it does not reflect the truth. Because these products have not gone through cosmetic controls, neither the amount nor the purity is known.

In Türkiye, cosmetic products are regulated by the Turkish Medicines and Medical Devices Agency (TİTCK); in the EU, by national authorities. Be wary of products whose labels lack information in your language or the name of a manufacturer or importer.

What to do when you see it on a label

If a cosmetic sold without a prescription lists “Hydroquinone”, the product does not comply with EU or Turkish legislation. The safest course for a pigmentation problem is to see a dermatologist. Cosmetic options use ingredients such as niacinamide, ascorbic acid (vitamin C), azelaic acid or retinol. Whichever product you choose, using a broad-spectrum sunscreen every day is the most important step in fading dark spots.