After a summer of long days in the sun and heat, you may notice that your skin appears redder than usual, particularly those who are prone to redness or rosacea. Luckily, there are things you can do to help bring this down; here’s our expert advice…
After a summer of long days in the sun and heat, you may notice that your skin appears redder than usual, particularly those who are prone to redness or rosacea. Luckily, there are things you can do to help bring this down; here’s our expert advice…
Retinoids are a group of ingredients derived from vitamin A (aka retinoic acid). Retinol is the most common retinoid used in skincare, however as time passes and legislation changes, we are seeing new generation retinoids such as retinal being increasingly used.
Dehydration is one of the most common skin conditions, affecting all skin types and ages. It is often mistaken for other skin concerns as it can cause sensitivity, flaky skin, fine lines, and even breakouts. Keep reading as we explain exactly how to tackle dehydration with advice from our in-house experts and brands of The Rehydrate Box.
Caused by environmental, diet and lifestyle factors - as well as neglect, age or an impaired skin barrier - dehydration is a temporary condition that occurs when there is a lack of water in the skin. This can present as tightness, fine lines and, in some cases, lead to flaking or an overproduction of oil. You might also find that products absorb quickly, and your makeup disappears by lunch.
The Rehydrate Box has, of course, been curated with dehydration in mind. It is the first ever Skin Rocks Box to feature one of our own products, and is also the final Skin Rocks Box we will make. We are finishing with a bang people!
Struggling with sunburn? Here’s our expert advice to calm scorched skin.
Appearing within a few hours of being in the sun for too long, sunburn is an inflammatory reaction to UV exposure. It usually causes the skin to become red, sore, warm and tender, with the skin often beginning to peel and flake within a few days. If this sounds like you right now, this is what you need to do:
The arrival of the brighter months brings a welcome influx of warmer weather, and with temperatures rising and longer, sunnier days on the horizon, it may be time to adjust your routine. Here are the essentials…
Pregnancy can be a beautiful journey, but the combination of hormonal changes and hot weather can pose challenges for your skin. Here are our expert tips and tricks to help you care for your skin during pregnancy and the summer season.
Ceyda Faik-Yildirim MSci (Chemistry) – Team Skin Rocks
The first ever Skin Rocks cleanser is here. Meet The Cream Cleanser: a conditioning cream formula to gently cleanse whilst respecting your barrier. Available in fragranced and fragrance-free versions, this luxurious cleanser is suitable for everyone. Read on to learn all you need to know.
Let’s set the scene. You’re going to an overnight festival - be that Glastonbury, Isle of Wight, Reading or any event that might involve sleeping in a tent - and need to compile a stash of skincare to take with you that you will actually use. While you’ll likely be having too much fun to even think about doing a full a.m. and p.m. skincare routine, we’ve created this simple guide to help you look after your skin while you’re there.
Your skin barrier is the outermost layer of your skin, that protects it from environmental aggressors and keeps your skin hydrated. If you have a damaged skin barrier, your skin may feel dry, tight, flaky, sore or look red. A compromised skin barrier may be caused by several different things such as cold weather, overusing actives or stripping the skin of its natural oils or from an allergy.
The Skin Rocks Treatment category has welcomed its latest addition - The Support Oil - your saviour treatment for all skins that need extra support and care. Read on for all you need to know about our brand-new treatment oil.
The very first launch of the Skin Rocks Moisturise category, meet The Moisturiser – a daily moisturiser to give you instant hydration and help support long-term skin health and radiance. The Moisturiser caters to those prone to sensitivity or who simply prefer un-fragranced products by offering a fragrance-free formula, as well as those who prefer a more sensorial experience with our signature light, refreshing, scented option. Read on to find out all you need about this A-star launch.
Facial oils can divide opinion and intimidate even the most experienced users, but they actually offer a number of skin benefits and can make a brilliant skin-boosting addition to your routine. Learn all about them in our guide.
While there are a variety of skincare myths that often circulate, retinoids draw particular attention. With this in mind, we asked board-certified dermatologist, Ranella Hirsch, to bust the most common myths around the gold-standard ingredient.
Heather Wish, Skincare Education Specialist at Paula’s Choice
Find out all you need to know about this all-star ingredient with Heather Wish, Skincare Education Specialist at Paula’s Choice.
What is azelaic acid?
Azelaic acid is a skin-friendly dicarboxylic acid* with unique properties that deliver:
Mild exfoliating action that helps unclog pores and refine skin’s surface
Skin tone-evening properties that visibly fade post-acne marks and other discolourations
Have you been using a retinoid for a while now and are ready to dial it up a notch? Here’s what you need to know.
What are retinoids?
The gold standard in skincare, retinoids (an umbrella term used for the various forms found in topical skincare), such as retinal, are derivatives of vitamin A – a key nutrient needed in order for our skin cells to function properly. They work by increasing skin cell renewal (the rate at which new skin reaches the top layer) and helping to stimulate key processes such as collagen and elastin production, altogether leaving the skin with a smooth, radiant and even appearance.
Find out all about the journey of the long-awaited Skin Rocks Skincare in our interview with Founder, Caroline Hirons.
When did you first decide you wanted to launch a skincare line?
I have a note in my phone from 23rd April 2013, so nearly 10 years ago, where I listed out what I would launch under a different name. These were my early thoughts of it, as I’ve always looked at overhyped claims and thought ‘if I had the opportunity, I would do it better than this’. Now, there is so much goodness in the industry that the thought has switched from ‘I will do better than this’ to ‘I want to do our best work’.
Loved by dermatologists and aestheticians alike, retinoids (aka vitamin A) are best known for their ability to significantly improve the appearance of the skin, particularly texture, wrinkles, breakouts and sun damage. Whilst the results can be impressive, many are hesitant to add a retinoid to their routine as they can be irritating ― especially when used incorrectly. Follow our advice to use your retinoid like a pro.
Before you start
Address any sensitivity. Before adding any new skincare product into your routine, make sure your skin isn’t irritated or sensitised. If it is, take care of any sensitivity first.
Start low. First-time users should begin with a low-strength/gentle formula and build up over time. Generally, once you’ve used up your current strength, you will be ready to move up a level, but always listen to your skin.
Slow and steady. It’s important to add your retinoid product into your routine slowly. Start off using it every third day before increasing to more regularly once your skin has acclimatised (unless the brand states otherwise). How often you use it will also depend on your skin’s tolerance, but as a general rule of thumb, you can use this guide: 2 times a week if you are a beginner or in your 20s, 3 times a week in your 30s and 4 times a week if you are over 40. Research has suggested that there is no additional benefit to using a retinoid more than 3-4 times a week1. So, in essence, every other day is a happy medium.
Go easy on the actives. When you first start using retinoids, we suggest going easy on the actives, particularly exfoliating acids (hydrating products are fine). Once you know your skin is tolerating it well, you can then re-introduce them on ‘non-retinoid days’ or in the mornings.
Here are some of our favourites for beginners:
Medik8 Crystal Retinal 3
Pestle & Mortar Superstar Retinoid Oil
Skin Rocks Retinoid 1
How to use
Brands will always provide you with instructions on the product packaging but for further guidance, follow our top tips:
Retinoids come first. Apply after cleansing and before the rest of your routine. For over-the-counter retinoids, it is optional to wait 20-30 minutes before applying anything else. Brands have traditionally advised applying on dry skin but we know that dampening the skin first (with a hydrating toner, mist or essence) can help with penetration. We advise against this if you have very sensitive skin. For prescription-strength formulas such as tretinoin, always follow the guidance provided by your doctor.
Protect your skin. Use at night and always make sure to apply SPF 30 or above during the day. Some newer brands have formulas that can be used in the morning but if in doubt, please use them in the evening.
More is not more. Apply a pea-sized amount (you can use slightly more for most OTC formulas) and distribute evenly across the face. With stronger formulas such as tretinoin, avoid the direct eye area (unless it’s a targeted eye cream), neck, around the nostrils and the corners of the mouth, as these areas are prone to irritation.
Your skin may react initially. Dryness, irritation, redness and flaking are all normal reactions when you first start using retinoids, particularly stronger formulas. During this stage, stick to a hydrating and nourishing routine until your skin builds tolerance. You’ll know you’ve overdone it if your skin stings when applying a simple moisturiser or feels like it’s burning/is sore. In this scenario, stop usage, go back to basics and give your skin time to recover before reintroducing slowly. The buffering technique will be helpful here.
The buffering technique. Whilst sophisticated formulas often contain nourishing ingredients; some retinoid products can be quite drying/irritating. To combat this, you can buffer its effects by applying a layer of moisturiser under your serum. This won’t stop your retinoid from working; it’ll just penetrate slower and mitigate any potential irritation or dryness.
Be patient. Retinoids are the gold standard in skincare for a reason - they work. However, consistency is key. While you will likely see some benefit after 4-6 weeks of use, full results can take up to 6 months. It’s worth the wait ― trust us!
Experienced retinoid user? Check out our top picks:
Paulas Choice 1% Retinol Treatment
Skin Rocks Retinoid 2
Sunday Riley A +
Shop our Retinoids here.
Words by Katie - Team Skin Rocks
Qualifications - BTEC, Beauty Therapy Applied Sciences
Hydroxypinacolone retinoate, or HPR, is a vitamin A derivative – a type of retinoid. It is also commonly referred to by its trade name, Granactive Retinoid, which has a slightly different meaning (more on this later). Before we deep-dive into this ingredient, let’s remind ourselves about retinoids and what they are.
What is a retinoid?
Vitamin A is retinoic acid. A retinoid is a vitamin A derivative. Some common examples of retinoids in skincare are retinol, retinal and retinyl palmitate. Retinoids have several skin benefits such as reducing the appearance of fine lines and wrinkles, reducing pigmentation and improving skin texture (for more on this, see our vitamin A Think Science ingredient glossary).
What is retinoic acid?
Retinoic acid is the active form of vitamin A. It is bioavailable to the skin (aka, it’s the form that your skin actually uses). So, when you apply any vitamin A derivative to your skin, it will need to convert to retinoic acid to have the same effect. You can read more about this in our ‘Vitamin A Stages of Conversion’ article, but the bottom line is that each conversion step needed will weaken the product - the fewer the conversion steps, the better. For context, retinol esters (such as retinyl palmitate) require a minimum of three conversions to reach the active form. Retinol requires two and retinaldehyde (retinal) requires just one step.
So, what is HPR?
HPR is an ester form of retinoic acid. It is unlike retinol esters, which require a minimum of three conversion steps to reach the active form; due to its close relation to retinoic acid (it is a retinoic acid ester), HPR does not need to go through the same steps of conversion as other retinoids do – it is already bioavailable to the skin as it is.
How does HPR compare to other retinoids?
If we had to rank HPR with other retinoids, in terms of efficacy, HPR sits at around the same level as retinal (i.e., more effective than retinol, less than retinoic acid), yet in terms of irritation, it sits around the same level as retinol esters (i.e., least irritating). Because of its ester structure, HPR is oil-based and is, therefore, gentler on the skin than retinoic acid. HPR has a low potential for irritation and is suitable for sensitive skin. Research has shown that HPR induced significantly less skin irritation than the same concentration as retinol, whilst still providing the same benefits to the skin. So, you can see why HPR is becoming more popular.
How is HPR different to Granactive Retinoid?
Granactive Retinoid is the trade name for HPR (think Nurofen vs ibuprofen). Trade names in cosmetics are used to describe blends of ingredients from specific suppliers. This is where we should talk a little about blend vs active ingredients.
Blend vs active ingredients
The simplest way to put it is that your active ingredient is mixed with another ingredient/other ingredients to make a blend. Think of dissolving a Berocca in a glass of water – imagine the Berocca is your active ingredient and your water is your solvent. Once fully dissolved, this is the form we consume – this is your blend.
So, Granactive Retinoid is the trade name for a blend of HPR (your active ingredient) plus solvent (in this case, just one solvent called dimethyl isosorbide). The solvent in this instance is added to enhance the delivery of HPR into the skin. Granactive Retinoid contains 10% HPR – the other 90% is your solvent. So, if your product is ‘2% Granactive Retinoid’, what this means is that it contains 0.2% of the active ingredient, HPR. Do be wary of this, as this labelling terminology can be confusing for consumers.
HPR-containing products we recommend:
Zelens Power A
The Ordinary Granactive Retinoid 2% Emulsion
Skin Rocks Retinoid 1
Skin Rocks Retinoid 2
Sunday Riley A+ High-Dose Retinoid Serum
Words by Ceyda Faik-Yildirim MSci (Chemistry) – Team Skin Rocks
Prescription* strength vitamin A is retinoic acid (also known as Tretinoin/Retin-A). This is the star of the show in terms of skin ‘care’. It has a long list of conditions/signs of ageing/skin problems/disorders that it is proven capable of either fixing entirely or massively helping. Originally (and still) used to treat acne, it quickly became obvious that there was such more to this wonder ingredient.
Retinoic acid is bioavailable to the skin. The difference between retinoic acid (Tretinoin/Retin-A) and retinol/retinaldehyde/retinol esters is that they need to be converted into retinoic acid by your skin at a cellular level in order to have the same effect.
Each one takes one further stage to convert, as per the table below, and each conversion weakens the strength/effect of the product, hence why a 1% retinol is still not as effective as a 0.025% retinoic acid but may prove more irritating:
retinoic acid/tretinoin/all-trans-retinoic acid (prescription only in the UK)0.1%0.05%0.025%
retinaldehyde and hydroxypinacolone retinoate (granactive)
(retinaldehyde – one conversion – acts quickly, just not as quickly as the above)(hydroxypinacolone retinoate is a retinoic acid ester – so it’s directly related to the Boss, but it’s not a direct descendant, more a cousin. Sometimes used in higher %s because it’s an ester and gentle)(Given the choice, I would still pick retinaldehyde over HPR.)
retinol(two conversions – still works, takes a little longer to get you there)1%0.5%0.3%
Retinol esters including :retinol propionateretinyl palmitate(three conversions minimum – these all differ but there is evidence showing that palmitate is the weaker of the family, more of which in individual reviews)There are other derivatives such as retinyl acetate and retinyl linoleate, but they are not as prevalent.
Added to the above are adapalene – trade name Differin, and tazorac, trade name Tazarotene.
Differin, now OTC in the USA, is mainly used in the case of acne, but has its own proven benefits on signs of ageing on the skin and so is an easy pick if you are state-side and looking for something affordable, easy to access and try, that won’t break the bank or your skin. It’s also safe for pregnancy and not a problem in the sun. I recommend Differin to anyone that isn’t contraindicated. It’s a no brainer.
Tazarotene is mainly prescribed for psoriasis and acne and is prescription only for a reason. It’s irritating and isn’t really used for cosmetic benefits, so if you are on that, keep talking to your doctor, I’m leaving it alone for the sake of ‘cosmetic’ reviews.
That’s it. The process is akin to coffee:
Shop our Retinoids.
*It is possible to buy tretinoin over the counter in mainland Europe with no prescription needed. When I am talking about prescriptions I am referring to the UK.
Do not forget your SPF. Avoid if pregnant, just for your own peace of mind. Retinoids are fine with breastfeeding**
**See video here with Dr Emma Wedgeworth.
Retinal, also known as retinaldehyde, is a type of retinoid. Retinoids are vitamin A derivatives – some common examples are retinal, retinol and retinyl retinoate.
Retinoids are widely known as the gold standard for reversing the signs of ageing such as fine lines and wrinkles. They can also reduce the appearance of hyperpigmentation and help to normalise skin function, reducing excess oil production and unclogging pores – making them beneficial for acne-prone skin.
Holly Daniels, Global Head of Education for Biossance
A hero product in The Best Version Of You Box, learn more about the Biossance Squalane + Copper Peptide Rapid Plumping Serum, including how to get the best out of the serum and how copper peptides support the skin as Holly Daniels, Global Head of Education for Biossance, reveals all you need to know.
Our serum utilises four key ingredients - copper peptides, hyaluronic acid, squalane and polyglutamic acid - to deliver instant and long-term hydration, plus visible firming for bouncy, healthy and plump skin. Here’s what makes these ingredients so effective:
Antonia Knox, Head of Brand and Product Expert at Aurelia London
You’ve probably heard of probiotics in skincare, but perhaps are unsure as to how they work and what it means for your skin. Here, Aurelia London’s Head of Brand and Product Expert Antonia Knox explains these fascinating ingredients and their best-selling Cell Revitalise Day Moisturiser, as found in The Menopause Box 2.0.
A key product in The Menopause Box 2.0, we asked NIOD to explain exactly how the ingredients in this intelligent mist work to protect and support the skin.
This product is a dermal treatment mist — not to be mistaken for a "toner" — that hydrates the skin while also helping to protect against environmental stressors and water loss, both of which, over time, may result in a loss of visible skin quality, such as thinning and dryness.
The products included in The Menopause Box are hand-picked by our Founder and Skincare Expert, Caroline Hirons. Read on to find out why she chose the products and to discover her top tips for dealing with menopausal skin.
Here to revolutionise the way you shop for and learn about skincare, discover exactly how the Skin Rocks App came to be as Journalist, Claire Coleman, sits down with our Founder, Caroline Hirons, to find out.
“Whenever I come up with something new, I normally message the team: ‘I’ve had an idea!’” says Caroline Hirons, explaining how the Skin Rocks app came about.
You’ve likely heard plenty about the radiance-boosting benefits of vitamin C but did you know that azelaic acid is another ingredient that can be effective at brightening the skin? Here, facetheory Education Manager Claire Balas tells us all we need to know about the ingredient and their best-selling azelaic acid serum as found in The Brightening Box.
The products included in The Brightening Box are hand-picked by our Founder and Skincare Expert, Caroline Hirons. Read on to find out why she chose the products and to discover her top tips for dealing with dull skin.
The cause of breakout-prone skin is varied and can be down to a number of reasons but first of all, let’s clear a few things up (no pun intended):
There is a difference between breakout-prone skin and acne.
Acne is a chronic skin condition.
'Breakout-prone skin' is skin that is consistently prone to breakouts every so often or on a consistent but sporadic basis.
You've probably heard a lot about acids in skincare. They sound a bit scary, but also excitingly powerful - what exactly do they do, and do you need to use them? Here's the lowdown on the most common acids in skincare.
As a board-certified dermatologist, Dr. Sandra Lee always urges people to resist popping their own pimples because it can often do more harm than good — making spots worse and leading to scarring and potential infection. She is aware however, that most of us will not listen to that. With this in mind, we asked for her expert advice on how to pop a spot properly.
When you think about breakouts you automatically picture a teenager with a few spots. But while there is still a stigma attached to the age we experience them, it is becoming more and more apparent that breakouts do not discriminate against age.
The products included in The Breakout Box were hand-picked by our Founder and Skincare Expert, Caroline Hirons. Read on to find out why she chose breakouts as a theme and why the products were selected.
Why did you choose breakouts as a theme?
Irrespective of your age or skin tone, if you have oily or combination skin and visible breakouts, this is the Box for you.
The Breakout Box came to fruition as we know that quite a few older people bought into our Teen Box. Breakouts are something many of us experience at some stage in our lives and so I wanted to create a targeted routine designed to decongest, soothe and balance blemish-prone skin.
Why did you choose these products?
Whether you’re experiencing large, painful, hormonal spots or a cluster of breakouts from a heavy weekend, I’ve chosen products that can help to tackle breakouts, no matter what the cause.
Paula’s Choice Skin Balancing Oil-Reducing Cleanser:
This gently foaming cleanser is ideal if you suffer from excess oil and blackheads. It removes dirt, oil and makeup without stripping the skin, thanks to the addition of glycerin and aloe vera.
Murad Daily Clarifying Peel:
Working over time to decongest pores and resurface the skin, this multi-action peel is a triple-threat when it comes to breakouts. Addressing both the cause of spots and appearance of congested skin, it uses a powerful combination of glycolic acid, salicylic acid and a retinoid.
If you are new to acids, please start by using twice a week. Increase if you feel it is necessary.
REN Clearcalm Replenishing Gel Cream:
When your skin feels oily, angry and congested, the last thing you want is a thick, heavy moisturiser. This soothing, lightweight gel cream is designed to boost moisture in breakout-prone skin, leaving it feeling calm and comfortable.
Votary Blemish Rescue Oil:
This oil has been designed as a sophisticated alternative to traditional spot treatments which can be quite drying. It’s brilliant if you suffer from regular breakouts and want an invisible treatment that can be re-applied throughout the day without stripping the skin.
What’s your advice for dealing with breakouts?
First and foremost, work out what might be triggering your breakouts. Is it your hormones? Stress? Your skincare routine? Each of these factors can lead to breakouts, so it’s important to identify the potential cause when treating them.
On that note, treat the spots, take care of the skin. Don’t treat your entire face as if it’s covered in breakouts (unless it is!). Spot treatments such as the Votary Blemish Rescue Oil included in the Box, are brilliant for targeting localised areas.
I’ve also created a complete guide on types of spots and how to deal with them which you can read here.
Shop The Breakout Box.
Co-founder of Summer Fridays and social media influencer, Marianna Hewitt is a self-confessed beauty fanatic. Prior to her popular brand launch, Marianna paved her way to over 1 million loyal followers by sharing her beauty knowledge, recommendations and natural passion for the industry.
Now, the successful co-founder is a podcast host and regularly interviews fellow brand founders, influencers, and personalities.
Looking to start your own beauty brand? Read on as we interview her on all things business and beauty.
Oh, the skin barrier. You will have likely heard of this being referred to A LOT within the skincare industry and while you might not know what it is, we’d bet good money that you’ve probably felt the backlash when it's become compromised (aka unhappy).
Contrary to common belief, sensitive skin isn’t a skin type. Caused by both genetic and external factors, sensitive skin straddles between a skin type and a condition. For some, it can be temporary, while for others, it’s chronic ― typically in those with a genetic predisposition or inflammatory skin condition.
As a consumer who has dealt with severe acne in the past, I found that my hyperpigmentation became a reminder of how I felt at the height of painful acne flare-ups. I began a personal journey of research to uncover effective ways to treat hyperpigmentation and hopefully educate my growing audience at the same time.
As soon as I mention the word ‘hyperpigmentation’ on social media, I am always met with an influx of questions and experiences from my community. While hyperpigmentation is not a new topic, there always seems to be a lot of confusion around it. Let's take a dive into some background knowledge on the subject.
Hyperpigmentation describes those pesky dark marks or areas we see on the skin which are usually the result of an inflammatory response. Excess pigmentation is caused by the overproduction of melanin by the melanocytes. This will occur after damage to the skin. The overstimulation of the melanocytes results in extra deposits of pigmentation appearing on the damaged area. The colour of the hyperpigmentation can give you an insight into the depth of the hyperpigmentation: grey hues indicate dermal melanosis, while brown indicates epidermal melanosis. Knowing how deep the lesion is will help guide you when choosing the correct treatment.
During my research, I discovered how much information and misinformation about hyperpigmentation flooded skincare spaces. A lot of the information that was credible required a very deep understanding of scientific language and biological processes – which would be a lot of faffing for someone who just wanted to treat their skin.
Something I noticed in my research is that the treatments I found useful for hyperpigmentation were not always the hyped-up treatments. One of the most popular products for treating hyperpigmentation is a Vitamin C serum. You cannot search hyperpigmentation without a Vitamin C serum popping up. Controversially, I do not find them useful for hyperpigmentation. I think this is because I saw how frustrated my community was becoming when trying to find the perfect Vitamin C serum and feeling like their hyperpigmentation would never reduce.
As mentioned earlier, hyperpigmentation is caused by the overproduction of melanin and, therefore, people with deeper skin tones are more likely to get hyperpigmentation and require a more intensive treatment other than Vitamin C. The key to truly effective treatment is to use products that help with inflammation and inhibit tyrosinase. However, while vitamin C does have tyrosinase-inhibitor properties, it is not the gold-standard treatment. There are many efficacious tyrosinase inhibitors besides Vitamin C and that is a hill I am willing to die on! Alternatively to Vitamin C, I am a huge fan of azelaic acid and kojic acid which are both amazing tyrosinase inhibitors. Azelaic acid at 20% is wonderful for treating both acne and pigmentation. Kojic acid is a little harder to get your hands on, but I am such a huge fan! Kojic acid can usually be found in consumer products at 1%, but is available at a higher percentage in a professional treatment clinic.
There is no way I could talk about hyperpigmentation without dispelling two of the most common myths.
Myth 1: ‘People with deeper skin tones should not use AHAs as they can cause burning or bleaching’.
This is super FALSE! Your skin tone does not dictate which ingredient you should use; your skin type (oily, dry, sensitive, normal) has more of an impact. I find this myth very damaging to a lot of people’s skincare journeys. Deeper skin tones can absolutely use AHAs, and I often recommend them. One tip I advise people to remember is that formulation of a product matters and you should not discount an ingredient based on one bad product experience (unless you are allergic to it).
Myth 2: ‘Hydroquinone is dangerous and illegal in the UK’
Hydroquinone remains the gold-standard tyrosinase inhibitor and it is NOT illegal in the UK, but it is available by prescription only. The main danger with using hydroquinone is obtaining it from an unregulated source or improper use.
The Pigmentation Box is a great example of treating hyperpigmentation in a multifaceted way and it is great for both pros and beginners to kick their pigmentation into line!
Desai S. R. (2014). Hyperpigmentation therapy: a review. The Journal of clinical and aesthetic dermatology, 7(8), 13–17.
Del Rosso J. Q. (2017). Azelaic Acid Topical Formulations: Differentiation of 15% Gel and 15% Foam. The Journal of clinical and aesthetic dermatology, 10(3), 37–40.
Punchard, N. A., Whelan, C. J., & Adcock, I. (2004). The Journal of Inflammation. Journal of inflammation (London, England), 1(1), 1. https://doi.org/10.1186/1476-9255-1-1