Hydroquinone: How it Works

To simplify the chemistry, hydroquinone lightens skin by inhibiting the enzyme tyrosinase. Tyrosinase is essential in the production of the pigment melanin. Low levels of melanin means lighter skin. This makes hydroquinone an effective ingredient in hyper pigmentation.

How Hydroquinone Works

Elucidating Issues

Despite its ability to lighten skin and treat hyperpigmentation , you might have heard about the safety concerns of hydroquinones  like the products below:

Famous Hydroquinone products in the Philippines. Do you know other products that contain hydroquinone? Comment below!

Let me start by saying that there’s an exaggeration and to some extent, fearmongering with regards to the safety of hydroquinone in lightening products. To date, 4% hydroquinone is still the most effective skin-lightening ingredient in topical skin preparations. It is very effective in treatment of hyperpigmentation, melasma and acne scars. However, there has been several published articles concerning its carcinogenicity, toxicity and other side effects.  Let’s go over to shed some light on these issues.

Hydroquinone is Carcinogenic

USFDA claims the ingredient to be a possible carcinogen based on a study that has seen development of tumor in mice-when orally ingested. However, a follow up study proves that the results were irrelevant in humans.  In fact after a thorough review on its safety, a study concluded that the ban of ingredient in EU countries is unnecessarily extreme.

Hydroquinone is toxic

A rare case that reported death after ingestion hydroquinone was a person who commit suicide by consuming a bottle of photograph developer which contains significant amount of hydroquinone. But like other SKIN care products in the market, you are not supposed to drink it because…

In fact, hydroquinone is present in nature in its “free form” in certain fruits. These include cranberries, blueberries, onions, rice, wheat bread and pears. Coffee and tea is also represent a significant source of free hydroquinone. Trust me, as someone whose brain wouldn’t function without coffee, I would have been dead if hydroquinone in my coffee is toxic. Besides, anything can be toxic depending on concentration (or its relative amount in a mixture).

 Hydroquinone can cause irritation or reddening of skin

Yes its true, but this is also true in all other active ingredient in other skin care products. Our skin reacts on different chemicals differently. There have been several reports of skin intolerance with hydroquinone, and so as other ingredients. It is important to perform spot test (or applying the product in small area of your face for 3 consecutive days) to check if there are adverse effects on your skin.

Hydroquinone can cause ochronosis or darkening of Skin.

See disturbing photo below

Image from http://www.news-medical.net/image.axd?picture=2016%2f8%2ffig-2-ocronosis-exogena.jpg

Yes it’s true – in rare cases of prolonged use with excessive sun exposure. The reason behind this is that (caution: nerd stuff coming) hydroquinone inhibits enzyme called homogentisic acid oxidase. This enzyme prevents the build-up of dark-colored homogentisic acid within the skin. With PROLONGED USE, it can cause ochronosis. Interestingly, chances of developing ochronosis is rare. However, it is important that you should avoid prolonged, continuous use of hydroquinone and without sun protection. Read on.

Things you should remember 

Hydroquinone is a proven treatment against acne, acne scars, and melasma. It is safe when used with proper precaution:

Wear sunscreen ALL THE TIME.

It is very important to use sunscreen during day time, all the time. Hydroquinone lightens skin and treats hyperpigmentation by decreasing the number of melanin. Remember that melanin plays an important role in absorbing UV in skin. Decrease of melanin content in skin makes you vulnerable to sun. To avoid UV damage, protect your skin from harmful UV rays through sunscreen. No matter how well the product is formulated, you can never see results when you don’t have effective sun protection.

Apply in the evening

For the same reason that your skin is more vulnerable against UV rays when under hydroquinone treatment.

Use Hydroquinone in 3 to 4 months cycle

Now this is very important – hydroquinone products should not be used continuously for more than 4 months. To keep its beneficial effects, use it 3-4 months cycle. For example:

Month 1-3: product with hydroquinone

Month 4-6: product with kojic acid, lactic acid, glycolic acid or arbutin

-repeat cycle-

This is to prevent the accumulation of  homogentisic acid and prevent skin damage.  When you have achieved results on specific issues like melasma or acne scars, you may stop using hydroquinone. Maintain proper exfoliation using other effective and safe exfoliants such as glycolic acid and lactic acid.

NEVER use with products containing BENZYOL PEROXIDE, HYDROGEN PEROXIDE or RESORCINOL 

Most acne treatment contains benzoyl peroxide and  resorcinol

These products are usually contained in anti-acne products that works by delivering oxygen in to the pores to reduce inflammation. Mixing these with hydroquinone will result to staining on skin. This stain can  be removed by soap but it is still best to avoid them. To be safe, avoid using strong acne and exfoliating skin products while under treatment.

Avoid eye Area

Hydroquinone can cause damage in corneal area. This only happens upon direct contact of eyes. It is important to avoid carelessly splashing some in your eyes. Also, it should not come in to contact with the thin layer of skin around  eye area.

Take Home:

I still use hydroquinone occasionally in spot treatments for acne and scars. If you are serious about specific concerns on hyperpigmentation, acne scars and melasma, I will still recommend it. Hydroquinone is safe and effective but should be used with precaution.

This article should not substitute advise of a professional. Visit your dermatologist prior to using hydroquinone in treatment for acne, melasma, or hyperpigmentation

 References:

(2006), JJ Nordlund, et al. The safety of hydroquinone, Journal of the European Academy of Dermatology and Venereology, pp 781-787

(2007) Jacob Levitt, The safety of Hydroquinone: A dermatologist response to the 2006 Federal Register, Department of Dermatology, Journal of Americal Academy of Dermatology, pp 854-872

(2006) O’Donoghue JL. Hydroquinone and its analogues in dermatology—a risk-benefit viewpoint. J Cosmet Dermatol, pp 196-203

(2003) Haddad AL, Matos LF, Brunstein F, Ferreira LM, Silva A, Costa D Jr. A clinical, prospective, randomized, double-blind trial comparing skin whitening complex with hydroquinone vs. placebo in the treatment of melasma. Int J Dermatology, pp 153-156

(2006) Guevara IL, Pandya AG. Melasma treated with hydroquinone, tretinoin, and a fluorinated steroid. Int J Dermatol 2001; 40:212-5. 75. Grimes P, Kelly AP, Torok H, Willis I. Community-based trial of a triple-combination agent for the treatment of facial melasma. Cutis, pp 177-184