Hydroquinone

Hydroquinone works by slowing tyrosinase, the enzyme that drives melanin production. This lets existing excess pigment fade faster than the skin replaces it, so dark patches lighten and your overall tone evens out. In the UK, Hydroquinone is available by prescription only, at any strength. This is because it is a powerful depigmenting agent that needs to be used in supervised courses to minimise risks and side effects. At City Skin Clinic, your doctor may prescribe Hydroquinone alone or alongside other actives, in a cream compounded for you, with a strength and protocol to suit your skin.

What Is Hydroquinone & How Does It Work?

Hydroquinone is a topical skin-lightening agent and the benchmark against which newer pigment-fading ingredients are still measured. It was first proposed as a skin-lightening agent in 1936 and has been the conventional standard for treating hyperpigmentation for more than 40 years. That long record is exactly why its benefits and its risks are so well understood.

Once absorbed, Hydroquinone works through reversible inhibition of tyrosinase, the key enzyme in melanin production. By slowing that enzyme, it lets the existing excess pigment clear faster than the skin replaces it, which is why dark areas gradually fade. Used correctly, it reduces excess pigment without bleaching the normal skin around it, and its effect is reversible. It mainly lightens pigment held in the upper layer of the skin (the epidermis), whilst deeper dermal pigment is harder to shift.

What Does Hydroquinone Treat?

Hydroquinone treats the skin concerns where excess melanin is the problem. It fades dark patches back towards your natural tone rather than lightening the skin as a whole. The main conditions Hydroquinone treats are:

• Melasma: a first-line topical for melasma, the hormonally driven brown patches on the cheeks, forehead and upper lip. Stubborn cases often need it combined with other actives.
• Hyperpigmentation and dark spots: fades general hyperpigmentation, including sun spots and age spots from years of UV exposure.
• Post-inflammatory hyperpigmentation: the marks left behind by acne, injury or inflammation respond well, making it a mainstay for post-inflammatory hyperpigmentation.
• Uneven skin tone: by treating the patches rather than the whole face, it helps bring your overall tone back into line.

How City Skin Clinic Uses Hydroquinone

We use Hydroquinone in several of our prescription skincare treatments, always as a cream, for both the face and body in suitable patients. Your doctor decides the strength, the base and whether it works alone or alongside other actives such as Tretinoin, Azelaic Acid or Niacinamide, based on your health, skin type, concerns, goals and wishes. Because every formula is compounded from scratch, your doctor chooses the strength that suits your skin, most commonly 4%, and may prescribe a higher or lower strength where appropriate. Hydroquinone also works best in defined courses, so your doctor plans the length of each course and any breaks, then reviews your progress before the next one. The treatments we may use Hydroquinone in include:

• Hyperpigmentation (face or body)
• Melasma
• Acne (post-acne marks)
• Skin Ageing

How Do You Get Hydroquinone in the UK?

Hydroquinone is a prescription-only medicine in the UK at any strength, so the only legal way to get it is with a prescription from a doctor or other qualified prescriber. It is also banned from over-the-counter cosmetics, which means any shop product or website selling it without a consultation is not a legitimate source. There is no fully licensed Hydroquinone medicine in the UK either, so it is supplied as an unlicensed compounded or imported medicine prescribed for you individually. The safe routes are a private dermatologist or skin clinic, or a regulated online clinic. Where to get Hydroquinone online in the UK compares the main options.

At City Skin Clinic, every treatment starts with a consultation. You can complete an online form or book a video appointment with your doctor, whichever you prefer. They will assess your skin, health and goals, decide whether Hydroquinone is appropriate and safe for you, then prescribe the right strength and protocol to start on. They’ll also decide whether other ingredients are worth adding to your formula, taking your wishes and preferences into account where possible. From then on, the same doctor follows you up throughout your treatment, including planning your next course and any breaks, and you can email them at any time.

There is no subscription and no auto-renewal. Each course is a single order you place yourself.

How Long Does Hydroquinone Take to Work?

Hydroquinone usually takes at least 4 to 8 weeks of consistent use to show the first signs of fading, with fuller results building from around 3 months onwards. However, this can take longer depending on the severity and depth of the hyperpigmentation. Pigment in the upper layer of the skin clears fastest, whilst deeper or longstanding pigment takes longer and may only partly respond. Results also depend on the cause. Sun-related dark spots and post-inflammatory marks often clear well, whereas melasma is more changeable and tends to need ongoing management rather than a one-off fix. Our guide to Hydroquinone covers what to expect in full.

What’s the Difference Between Compounded Hydroquinone, Generics & Brands Like Obagi Clear or Blender?

Compounded Hydroquinone is made individually for one named patient by a specialist pharmacy to a doctor’s prescription, like our treatments. This lets your doctor set the exact strength, choose the base and add complementary actives such as Tretinoin in a single product. The trade-off is that compounded medicines are unlicensed and freshly made, so they carry shorter expiry dates, usually 1 to 3 months (ours are 3 months).

Off-the-shelf Hydroquinone comes as generic products or brands, most famously the Obagi prescription ranges. Obagi Clear is a 4% Hydroquinone cream for once or twice daily use, whilst Obagi Blender contains the same 4% strength and is designed to be mixed with Tretinoin or retinol at night. These products are manufactured at fixed strengths and have long expiry dates before opening. None of them is licensed in the UK, so they are also supplied on prescription as unlicensed medicines. Whether compounded or off-the-shelf, the Hydroquinone molecule is exactly the same. The difference is the formulation around it.

How Do You Use Hydroquinone?

Use Hydroquinone exactly as your doctor directs; your treatment plan sets your strength, how often to apply it and how long each course runs. As general guidance, it is applied once or twice a day as a thin layer. Spread it evenly across each affected area rather than dotting the darkest spots, because patchy application creates patchy lightening, and your doctor will tell you whether to treat a small area or more widely. Keep it away from your eyes and mouth, and do not apply it to broken or sunburnt skin.

Hydroquinone is not a use-forever product. It is used continuously in courses of up to 3 to 6 months at a time, followed by a break to reduce the risk of side effects. Daily broad-spectrum sunscreen of at least SPF 30 is essential whilst you use it and well worth continuing afterwards, because UV exposure drives pigment straight back. Your doctor will also tell you how to handle other actives. Benzoyl peroxide is the main one to keep apart, because the two can react and temporarily stain the skin.

What Are the Side Effects of Hydroquinone?

The most common side effects of Hydroquinone are mild irritation, redness and dryness, particularly in the first weeks and in people with sensitive skin. Less commonly, irritation can amount to contact dermatitis, and in some people that irritation can itself trigger more pigment, particularly in deeper skin tones, which is why a gentle, supervised approach matters. Some people notice excessive lightening of the normal skin around a treated patch, which is reversible. An allergic reaction, with itching, swelling or marked redness, means you should stop and get in touch straight away. Rarely, continuous use stretched well beyond a planned course, or high-strength unsupervised use, can cause exogenous ochronosis, a blue-black discolouration of the skin that is difficult to treat and may be permanent. These problems almost always come from unregulated, high-strength products used indefinitely without supervision, which is exactly why Hydroquinone is prescription-only and used in supervised courses with breaks. If any side effects occur, contact your doctor. We would either pause the treatment or adjust it to a strength and frequency you can tolerate. The guide to Hydroquinone covers its side effects in full detail.

Who Should Not Use Hydroquinone?

Hydroquinone is not suitable for everyone. It is not recommended during pregnancy or breastfeeding, so treatment can only start once both are finished. That matters here because melasma often first appears in pregnancy; our pregnancy skincare guide covers safer ways to manage pigment in the meantime. Its safety and efficacy are not established in anyone under 12. Tell your doctor if you have eczema, a fish allergy or any sores, burns or open wounds, and let them know about any allergies to Hydroquinone or similar products. You must not use it if you have or develop an allergy to any of the ingredients in your formula.

Darker skin tones are not a reason to avoid Hydroquinone. It is effective and widely used in skin of colour, though the risk of ochronosis runs higher, so supervised courses with planned breaks matter even more. This is one of the reasons we never recommend buying it from unregulated sources.