If you talk about hyperpigmentation, there is one ingredient you are bound to get questions about: Hydroquinone.
Is it effective?
Is it safe?
Or will it make my skin turn blue and give me cancer?
If you have asked yourself any of these questions, then keep reading – this blogpost is for you.
How hyperpigmentation happens
Before I get into the ingredient, a few quick words on hyperpigmentation. I have a whole series answering your questions about that topic that I am going to link here and I suggest you read this one about the different forms of hyperpigmentation first, where I explain why the brown patches actually appear.
As a quick recap: The melanocytes, when activated, covert Tyrosin into DOPA via an enzyme called Tyrosinase. To prevent that, we use Tyrosinase-Inhibitors, and one of them is Hydroquinone.
Where does Hydroquinone come from?
Hydroquinone is a phenol and present naturally in pears, tea and coffee as well as in the glands of the bombardier beetle that in case of danger mixes Hydroquinone with Hydrogen Peroxide and the enzyme Katalase to squirt that hot and etching mixture on its enemies. Little fun fact here to keep your attention!
Leaving bombardier beetles aside though it occurs naturally in several plants, both as hydroquinone or as it well-known precursor, Arbutin.
What does Hydroquinone do?
Hydroquinone creams are often referred to as skin-bleaching creams, which is misleading. When I hear „bleaching“, I think destruction of already existing pigment, and Hydroquinone does not affect the pigment present in your cells. What it affects is the production of new melanin, so rather than actually bleaching the skin, it will prevent it from getting darker.
Might be semantics to some, but you know I am a fan of exact descriptions. The effect however when applied to the skin is the lightening of dark patches or, when applied all over the face, the lightening of the skin tone in general, simply because the melanocytes aren´t able to convert as much Tyrosin into DOPA.
How long does it take to see results and are these results permanent?
As always with skincare, you need patience.
Hydroquinone will not give you overnight effects. Many people do see a significant reduction in pigmentation intensity within the first few weeks though, which is considered lightning speed when it comes to treating hyperpigmentation – it usually is a painfully slow process!
As I mentioned in the first blog post of this series though, hyperpigmentation is a chronic condition that might come back if you stop the treatment, so no, the results are not permanent. That doesn´t mean that you will need to use Hydroquinone for the rest of your life (you shouldn´t anyway, but we will get into that in a bit).
While you still have the melanocytes that will produce melanin when activated, the process the Hydroquinone blocks, you can prevent this activation once the hyperpigmentation has faded, by wearing broad-spectrum sunscreen for example (read more about sunscreen here). That way the effects will be preserved even after you stopped using the Hydroquinone although they are not premanent – I hope that makes sense the way I explain it.
How is Hydroquinone used in treatment?
I am only going to give very general treatment information now, because I don´t want you to treat yourself with only this blog post as guidance!
But in general Hydroquinone is available as creams, lotions, gels or solutions and comes in concentration of up to 2% that are available without prescription and in concentrations of 4%, which is a prescription in most countries.
The treatment is applied to the pigmented patch and the surrounding areas of the skin and the duration of the treatment should not exceed four to six months, with a break afterwards.
Due to the irritating nature of the ingredient I would be hesitant to mix it on my own with other potentially irritating ingredients like Vitamin C, AHAs or retinoids, but as that led to some confusion under my previous blog post on mixing ingredients: if you are prescribed a mixture by your doctor, you should of course follow their advise!
Does Hydroquinone have side effects?
Yes. Some that are pretty common in skincare and others that have led to Hydroquinones (mostly undeserved) bad reputation.
The side effects it shares with other ingredients like retinoids or AHAs are dryness, redness and irritation and are hugely influenced by your individual skin and the dose and frequency you use.
But of course no one really talks about them, what usually is mentioned are either a confetti like depigmentation of the skin, leukodermie, or the so called pseudo-ochronosis or exogenous ochronosis.
Leukodermie means real depigmentation of the skin, which is especially noticeable in darker skin types and is not reversible.
Pseudo Ochronosis (opposed to ochronosis that happens as part of a genetic disease that affects an enzyme in the Tyrosin metabolism) is due to an accumulation of Homogentisat or homogentic acid. Homogentic Acid is a chemical that occurs when Hydroquinone is broken down and can, when too much is present, be deposited in the joints, the sclera, which is the white of the eye, and the skin. This deposition leads to a blue-sih grey pigmentation that is not reversible.
Pseudo ochronosis is not only described in case reports after hydroquinone use, but also as side effect of anti-malaria or anti-parkinson medication and seems to be associated with dark skin and consistent use of a higher doseage.
It is important to emphasize though that
- Food and beverages, especially coffee or tea, are associated with consumption of Hydroquinone in larger quantities than it is absorbed through the skin when used as advised
- We only have case reports, which means the actual incidence is either extremely low or not well documented, especially if we take into consideration that Hydroquinone has been used since 1936 and has been examined via studies since 1961, so for… 59 yeras now!
- It is not safe to conclude that the fact that these case reports are exclusively from People of Color that means that the risk for people of color is higher – in most cases continous use over large areas of the body was reported as opposed to localized treatment of hyperpigmentation. That doesn´t mean the risk is the same, I am merely saying we don´t know that for sure and Hydroquinone has been used safely under dermatological control on people with color without side effects, so…
If you are considering using higher concentrations of Hydroquinone, make sure to do so under professional supervision, especially if you have black skin.
How about Hydroquinone and cancer?
Another thing you can hear often is that Hydroquinone can be linked to renal cancer, a conclusion that was drawn after rats that were fed high doses of Hydroquinone showed an increased rate of renal dysplasia. There are a few problems with transferring these results to humans though.
First, we are no rats.
Second, we are used to ingesting Hydroquinone via food and beverages, while rats usually don´t have a morning coffee, so are far worse equipped with enzymes to break it down.
Third, the doses fed to the rats are much higher in relation to the body weight than the doses we ingest via beverages, which are in turn much higher than the ones we absorb over the skin.
Fourth, as I mentioned above, Hydroquinone has been used since 1936, so I reckon that if it would increase the risk for renal cancer, we would have noticed that by now.
Is Hydroquinone banned in Europe?
I have seen this over and over again, but no, Hydroquinone is not banned in Europe. It is just prescription once it exceeds a concentration of 2%.
Hydroquinone is a safe and effective treatment for many forms of hyperpigmentation, but should always used according to the advise of a professional if it exceeds concentrations of 2%.
It is very often used as first line treatment for melasma and can give very good results, but requires continouus upkeep of preventative measures like broad spectrum sunscreen if you want to keep those results in the long term.