The ESK blog

The Safe And Effective Answer To Pigmentation: 4-n-Butylresorcinol

20 July 2021

Hyperpigmentation has a number of different causes, is triggered deeper in the Dermis and can be difficult and require a long term approach to treatment to treat.

There are 4 pathways through which topical depigmentation can be achieved:

Anti-oxidants: Eg. Vitamin C, which neutralise the signal created by UV exposure, to create melanin

C Serum Lite

C Serum Lite offers the same evidence-backed benefits of Vitamin C in a lighter, non-greasy formula. Packaged in an airless, opaque bottle to maintain stability for maximum effect, this anti-oxidant serum is perfect for use every morning. Designed for a lightly hydrated, brighter and smoother looking skin.

Key Benefits

- Helps create a more even skin tone

- Supports smoother-looking skin and reduces the visible signs of skin aging

- Evidence-based ingredients for hydration and firmness

Reduction of Melanin transfer: Eg. Vitamin B3 reduces the transfer of melanin (carried in melanosomes) to keratinocytes where it is deposited (as pigment)

B Calm

B Calm is formulated to support irritable and blemish prone skin while maintaining a healthy skin barrier. Ceramides strengthen resilience, Salicylic Acid exfoliates and calms the skin, and Niacinamide helps regulate oil and reduce the appearance of blemished skin.

Featuring:

- Ingredients to support an improved skin barrier

- Helps manage excess oil production

- Supports a clearer-looking skin

B Quenched

Meet B Quenched, a gentle hydrator designed for irritable skin. Powered by niacinamide and hemp seed oil, it helps support the appearance of a calm, hydrated skin barrier, while helping reduce visible redness. Free from scents, parabens, and sulphates, this pH-balanced formula locks in moisture and keeps irritants at bay. B Quenched leaves skin feeling soft, balanced, and refreshed, perfect for daily use.

Key Benefits

- Helps improve the appearance of hydration and softness

- Supports calm-looking, less inflamed skin

- Evidence-backed ingredients to maintain a resilient skin barrier

Increased skin cell turnover: Eg. Glycolic acid and Vitamin A – flushes melanin in the skin

Ultimate A

Ultimate A Night Cream contains 0.06% Retinal, the most gentle and effective form of Vitamin A, paired with Niacinamide to help maintain skin barrier function and support brighter, firmer and more even looking skin tone and texture. Well suited even for the most irritable skin.

Key features:

0.06% Retinal to support a brighter, smoother and firmer skin texture
Niacinamide to support skin barrier function and a more even looking skin tone
Gentle formulation suitable for nightly use

Usage: Apply at night after cleansing (and serum if being used) as part of your evening skincare routine.

Ultimate A+

Building on the proven performance of Ultimate A, Ultimate A+ Night Cream is designed for those looking to refine texture and tone or support skin prone to congestion. With 0.1% Retinal (the next-generation form of Vitamin A), Niacinamide, and 2% Glycolic Acid, this formula delivers visible improvements while remaining gentle and well tolerated.

This unique combination supports smoother-looking skin, helps refine the appearance of pores and uneven tone, and promotes a more hydrated, balanced complexion.

Featuring:

Potent yet gentle formulation suitable for daily use
Helps improve the appearance of uneven tone and texture
Supports firmer, more supple-looking skin
Formulated with evidence-based ingredients known to enhance skin clarity

Note: Retinal is not suitable for use during pregnancy.

Tyrosinase inhibition: Eg. Hydroquinone (and 4-n-butylresorcinol) targets Tyrosinase, the precursor which is involved in creation of melanin.

Enlighten

Enlighten is specifically designed to help reduce the appearance of pigmentation. This lightweight cream helps to gently create a more even skin tone and hydrate and improve the barrier function of the skin.

While rarely used, 4-n-butylresorcinol (4nB) has some of the best evidence in this arena. Enlighten combines 4nB and Niacinamide (Vitamin B3) to create a rare combination of gentle yet effective ingredients. Enlighten helps tackle a mottled or uneven skin tone and is suitable for long term daily use

Featuring:

Formulated to help skin look brighter and more even
Gentle, nourishing ingredients suitable for daily use
Supports the appearance of an even skin texture and tone

While best results are available by targeting multiple pathways at the same time, Tyrosinase inhibition is the most effective pathway to tackle pigmentation. But it is also the slowest, with treatments often only starting to show results after 1 ½ to 2 months. That said, some depigmentation ingredients (like Vitamin A) can take 2 years to start showing results.

Of the Tyrosinase inhibition group, Hydroquinone is the “gold standard” ingredient , but it has for some time had a cloud over its safety profile and potential to irritate. The evidence for other ingredients in this group which includes Arbutin, Azelaic Acid, and Kojic Acid is not as strong as Hydroquinone, and these ingredients can be irritating and in the case of the Kojic Acid, also have some concerns around their safety. As a result there has been a significant amount of work done on alternate Tyrosinase inhibition ingredients in the search for one that is safe, well tolerated and effective.

A relative new-comer to this group is 4-n-Butylresorcinol – pronounced “4 N beautal resorcinol” – (a.k.a 4nB, 4 Butylresorcinol or Rucinol). The first study on 4nB was published in 1995, but it wasn’t until 2005 that another study was published, with the first trials on humans being published in 2007 . Since then, repeated human clinical trials have shown good results, low irritation, high tolerance and good safety results.

While there have been no head-to-head trials of 4nB and Hydroquinone the relative ability of common Tyrosinase inhibition ingredients to perform their core task has been studied. And when 4nB was compared to Hydroquinone, Arbutin and Kojic acid, it demonstrated superior tyrosinase inhibition ability.

Based on the evidence to date, in the search for an alternative to Hydroquinone, 4nB has been demonstrated to be the most effective depigmenting agent producing less irritation than the alternatives. But in the words of others taking into account its fast onset of action, once-a-day application, and a wide range of indications, this promising (4-n-Butylresorcinol based) product may be a revolution both in treatment of melasma and in skin rejuvenation.

Having found this, we created the Enlighten face cream (can be purchased individually or with a tailored kit) to specifically target hyperpigmentation and age spots using 4-n-Butylresorcinol. See how our Pigmentation Kit has improved the skin tone of customers:

Pigmentation Kit

The Pigmentation Kit combines evidence-based ingredients designed to support a refreshed skin and a more even skin tone while restoring hydration.

Key features:

Supports the appearance of a more even skin tone.
Hydrating formulations to support skin barrier function.
Ultimate A Gold replaces Ultimate A; you can build your own kit if you prefer Ultimate A.

Retinal is not suitable for use during pregnancy or while trying to conceive.

C Forte can exacerbate acne and may be too strong for irritable skin.

We've swapped Ultimate A with the new Ultimate A Gold. If you prefer Ultimate A, you can build your own kit here.