Ingredient Deep Dive: Hydroquinone

Do you have hydroquinone on your skincare radar? It’s one of the leading ingredients used by dermatologists to treat hyperpigmentation. 

Here, we’ll take a closer look at what hydroquinone actually is, how it treats hyperpigmentation, how you should use it, possible side effects and any other bits of juicy info you need to know.

What is hydroquinone?

Hydroquinone is commonly used as a primary ingredient for inhibiting melanin production. In reducing the skin’s production of melanin, it can reduce hyperpigmentation. 

Here’s the science-y bit: In healthy skin, melanocytes convert tyrosine into melanin. Hydroquinone acts through reversible inhibition of tyrosinase with selective melanotoxic action. This stops new melanin synthesis, and it’s a pretty useful bit of science to know.

How does hydroquinone treat hyperpigmentation?

Our skin’s natural colour is determined by a pigment called melanin that’s produced by cells in the top layer of our skin. Hyperpigmentation most commonly occurs when melanin is overproduced, which can lead to dark spots or patches on the skin’s surface. 

It’s a super common problem and can be triggered by a number of underlying skin conditions and environmental factors. Hydroquinone works by reducing the skin’s production of melanin. This reduces the risk of post-inflammatory hyperpigmentation (or PIH), solar lentigos and melasma – three common types of hyperpigmentation. 

How do you use hydroquinone?

Consistency is key with this ingredient. With a prescription from your dermatologist, you should be able to seamlessly add hydroquinone into your daily skincare routine. 

For best results, you will most commonly be prescribed a triple combination cream containing hydroquinone as well as the vitamin A derivative tretinoin and a mild steroid. This combination. has been found to be more effective in treating hyperpigmentation compared to the treatments when used alone.

Top tip #1: Apply after cleansing but before moisturising. Massage a small amount of the product into your skin until completely absorbed. Make sure you wash your hands after use. You don’t want the powerful product ending up anywhere else and affecting other areas of the skin. 

Top tip #2: Always wear sunscreen when using hydroquinone. Not only can the sun’s rays make hyperpigmentation worse, especially solar lentigos (or sun spots), but it can also actually reverse the effects of the treatment. 

Does hydroquinone have any side effects?

Hydroquinone can cause further dryness or irritation when initially used and caution has to be taken in people with dry or sensitive skin.

However, this commonly eases once the skin has fully adjusted to the new ingredient on its surface. Those with more normal to oily skin types will be less likely to experience this dryness or irritation. 

Ochronosis is a condition that results in blue, black and grey marks on the skin and can be caused by excessive use of hydroquinone. The majority of cases of ochronosis were linked to the use of very high concentration. of hydroquinone several times a day for several years. No cases of ochronosis have been reported when hydroquinone is used at concentration between two and five percent, for short periods of time under medical supervision. 

There have been reports and association of cancer with the use of hydroquinone – it’s important to point out that these were only seen in animal studies and when hydroquinone was used orally. There have been no reports of cancer in humans.

Hyperpigmentation can be a difficult condition to treat and it can look different on everybody. As we are all unique and so is our skin. Although hydroquinone may help lighten areas of hyperpigmentation, this ingredient isn’t appropriate for everyone so it’s always good to check in with your skin and listen to it if it doesn’t seem happy.

The take-aways

Hydroquinone can be used to treat skin conditions related to hyperpigmentation including acne scars, age spots, freckles, melasma and post-inflammatory marks from psoriasis and eczema. However, you should make sure to check with your dermatologist before use, especially if you have dry to sensitive skin or a darker skin tone as hydroquinone can worsen hyperpigmentation in skin tones that are darker. 

The bottom line is that when used under supervision – which means regular medical review and for short periods of time such as eight weeks – hydroquinone is regarded as safe to use.

Dermatologists should reassure patients that with controlled use, hydroquinone can be well-tolerated and safe for a range of hyperpigmentary conditions.

Medical facts checked by Consultant Dermatologist,  Dr Malvina Cunningham.