Skin actives are all the rage – from retinol to niacinamide, vitamin C, azelaic acid… the list goes on.

Boosting your skincare routine with actives can truly transform your skin. But introducing these ingredients to your delicate skin barrier should be done with a good degree of caution.

Specifically, hydroquinone is a powerful active ingredient and should be used under the guidance of a qualified healthcare practitioner. 

But what are the benefits of using hydroquinone, and how can you incorporate it into your skincare routine? Let’s dive in.

What is hydroquinone?

“Hydroquinone is a skin-lightening agent. It can be used to achieve an overall lighter skin tone or to fade troublesome areas, such as age spots and melasma. Hydroquinone is regarded as the gold standard for treating pigmentation,” said Dr Lauren Thomas, a doctor at Software.

Hydroquinone can be used to treat common skin conditions like post-inflammatory hyperpigmentation (dark spots left on your skin after pimples or injury), age spots and facial melasma.

It’s typically found as a prescription product however, hydroquinone is available at lower strengths (about 2 per cent) in very select over-the-counter products. However, it remains most commonly available product in clinical-grade cream formulations.

How does hydroquinone work?

“Hydroquinone works by slowing down the production of melanin, which is a type of pigment that occurs in the skin and gives it its brown colour,” said Dr Thomas.

“People with light skin and dark skin have the same number of melanocytes, which are the pigmentation-producing cells – the difference is that different people’s melanocytes will produce different amounts of melanin. In certain people, their melanocytes can start to produce excess pigmentation.”

Some of the most common risk factors for developing hyperpigmentation include pregnancy, the use of oestrogen-containing contraception, smoking, excessive sun exposure and stress.

These factors can also contribute to melasma. Melasma is more common in people who tan easily and, in general, those with darker skin types.

How to use hydroquinone, according to a doctor

Hydroquinone is most typically used as a spot treatment. It’s recommended to apply it in a thin layer and gently massage it into the affected areas twice daily for about three months.

It’s important to note that side effects can result from excessive use of hydroquinone. Using it for longer than four months at a time can carry a risk of causing exogenous ochronosis, a greyish-blue pigmentation that is much harder to get rid of than other types of hyperpigmentation.

As a result, it’s recommended to take a break of several weeks from hydroquinone use in between treatment cycles before it can be used again. 

Taking scheduled breaks can also prevent the risk of tachyphylaxis, a phenomenon where the skin begins to acclimate to certain topical treatments, resulting in them becoming less effective over time.

“Hydroquinone is a strong ingredient which means it can cause some redness, stinging, and dermatitis. It is very important while using it to wear sunscreen every morning, even if not leaving the house. One day in the sun can undo nearly a month of treatment,” explained Dr Thomas.

It’s also recommended to wash your hands after applying hydroquinone to prevent any risk of discolouring the fingernails.

Can you combine hydroquinone with other skincare ingredients?

Typically, hydroquinone is safe to use in conjunction with other skincare actives as it has no known severe, serious, moderate or mild interactions with any other ingredients. 

One of the benefits of typically finding hydroquinone in a compounded formulation is that it can be mixed with additional ingredients to help with pigmentation in the same formula, including vitamin C, kojic acid and tretinoin.

What happens if you stop using hydroquinone?

“If you stop hydroquinone, there may be some return in pigmentation. However, this is dependent on whether the risk factor is still present. For example, if you’re no longer pregnant and no longer on oestrogen contraception it may not come back. It is not safe to use while pregnant or breastfeeding,” said Dr Thomas.

It’s important to remember that hydroquinone is a powerful skincare ingredient and should always be used under the guidance of a licensed healthcare professional. Make sure you consult with your doctor first about when to start using it, how long to use it for, and how you should stop using it.