Sleep Glycolic
Sleep Glycolic
Product Description
Product overview
A high-strength overnight AHA peel with 10% encapsulated glycolic acid that uses crystal time-release technology to brighten, smooth, and decongest skin while you sleep — delivering professional-grade results with zero downtime.
Crystal Encapsulation Technology
Glycolic acid is encapsulated in a cyclodextrin crystal shell that slowly breaks down overnight, delivering the active gradually to minimise irritation while maximising efficacy.
Texture & feel
SENSORYCrystal Encapsulation Technology
Glycolic acid is encapsulated in a cyclodextrin crystal shell that slowly breaks down overnight, delivering the active gradually to minimise irritation while maximising efficacy.
Professional-Grade Results at Home
With a true 10% free acid value at pH 3.5, this delivers potent exfoliation comparable to in-clinic peels — ideal for maintaining results between professional treatments.
Barrier-Friendly Formula
Non-drying formula enriched with glycerin and Korean clover extract supports the skin barrier and overnight repair, preventing the dehydration common with other acid peels.
Zero Downtime Overnight Peel
Leave-on treatment works while you sleep with minimal tingling. No redness, no flaking — just visibly brighter, smoother skin by morning. Use only 2-3 times per week.
Safety & compatibility
SAFEMedik8 advises consulting your doctor before use during pregnancy or breastfeeding. Glycolic acid at 10% is a strong active; professional guidance is recommended.
Contains Polysorbate 60, Caprylic/Capric Triglyceride, and Sorbitan Isostearate which may feed malassezia yeast. Not recommended for fungal acne-prone skin.
Rated 1/5. The lightweight milky serum formula is unlikely to clog pores. Glycolic acid itself helps to decongest and clear pores.
Glycolic acid increases photosensitivity. You must wear SPF 30+ the morning after every use, and for a week after stopping use. Evening-only application is essential.
Can be used alongside vitamin A products (e.g., Crystal Retinal) once skin has completed the phase-in period. Do not combine with other leave-on acids in the same routine.
As a high-strength 10% glycolic acid product, patch testing is advised before first use, especially for those new to chemical exfoliation.
Ingredient breakdown
INGREDIENTSGlycolic Acid 10%Proven
The smallest AHA molecule, glycolic acid penetrates deeply into the skin to break bonds between dead cells, revealing smoother, brighter skin. At 10% free acid value with pH 3.5, this is a highly active concentration for effective exfoliation.
- Mechanism: Dissolves the intercellular cement holding dead cells together on the skin surface
- Clinical data: 97% agreed it smoothed skin surface; 95% reported visibly brighter tone (user trial, 34 participants, 4 weeks)
- Long-term: With consistent use, glycolic acid stimulates collagen production and increases hyaluronic acid content in the skin
Cyclodextrin EncapsulationProven
A cyclodextrin-based crystal shell that encapsulates the glycolic acid. On contact with skin, this shell slowly breaks down throughout the night, delivering the acid gradually rather than all at once.
- Benefit: Time-release delivery significantly reduces irritation, redness, and peeling compared to free glycolic acid
- Technology: Crystal encapsulation is a patented Medik8 approach, also used in their Crystal Retinal range
Glycerin HumectantProven
One of the most effective and well-researched humectants in skincare. Draws moisture from the environment into the skin, keeping it hydrated and preventing the dryness often associated with acid treatments.
- Role: Counteracts any drying effects of glycolic acid to maintain a healthy, hydrated barrier
- Compatibility: Universally well-tolerated across all skin types
Korean Clover Extract (Lespedeza Capitata) BotanicalPromising
A botanical extract derived from Korean clover (bush clover). Supports the skin's natural overnight repair and hydration processes, complementing the exfoliating action of glycolic acid.
- Benefits: Rich in polyphenols and flavonoids with antioxidant and soothing properties
- Function: Helps support overnight skin recovery while glycolic acid works to resurface
Dimethicone SiliconeProven
A lightweight silicone polymer that creates a breathable protective barrier on the skin. Gives the formula its smooth, non-greasy finish and helps to fill fine lines for an instantly plumped appearance.
- Function: Occlusive barrier locks in moisture and active ingredients without clogging pores
- Texture: Contributes to the milky, smooth application feel
17 ingredients
Aqua (Water), Glycolic Acid, Cyclodextrin, Caprylic/Capric Triglyceride, Dimethicone, Glyceryl Stearate, Sucrose Stearate, Sodium Hydroxide, Glycerin, Phenoxyethanol, Lespedeza Capitata Flower/Leaf/Stem Extract, Propanediol, Xanthan Gum, Ethylhexylglycerin, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Polysorbate 60, Sorbitan Isostearate.
Where it fits in your routine
ROUTINEPM only, 2-3 times per week. As a direct acid, Sleep Glycolic goes immediately after cleansing — layer all other serums and moisturizers on top. Always apply SPF 30+ the next morning.
How to use
HOW TO USECleanse
Wash your face thoroughly with a gentle cleanser in the evening and pat dry.
Apply Sleep Glycolic
Smooth a pea-sized amount onto the face, neck, and décolletage. Avoid the eye area. A slight tingling sensation is normal.
Layer Your Routine
Follow with your other serums (e.g., retinal, peptides) and finish with a night moisturizer. Leave Sleep Glycolic on overnight.
Morning SPF
The next morning, apply a broad-spectrum sunscreen (SPF 30+). Glycolic acid increases sun sensitivity, so SPF is essential.
Who is it for?
WHOPerfect for you if:
- You want visibly brighter, smoother skin with minimal effort
- You have dull, uneven, or congested skin
- You want to maintain results between professional peel appointments
- You're new to chemical peels and want a gentle introduction
- You have concerns about fine lines, wrinkles, or hyperpigmentation
- You want a leave-on overnight treatment with no downtime
Consider alternatives if:
- You have very sensitive or rosacea-prone skin
- You have fungal acne (malassezia) — formula contains potential triggers
- You already use multiple strong actives daily and need a gentler option
- You want a daily-use exfoliant (this is 2-3x/week only)
- You are pregnant or breastfeeding without doctor approval
- You cannot commit to daily sunscreen use
Skin type compatibility
SKIN TYPESDecongests pores and controls excess oil buildup. Non-greasy milky serum absorbs beautifully without adding shine.
Glycerin and Korean clover prevent dryness, but always layer a rich moisturizer on top. May feel slightly drying for very dry skin types.
Balances well across different zones. Evens out texture and tone differences between oily T-zone and drier cheeks.
Time-release technology reduces irritation, but 10% glycolic acid is potent. Patch test first. Medik8 does not recommend for very sensitive skin.
Helps to clear congestion and breakouts through exfoliation. Low comedogenic rating (1/5). However, not fungal acne safe.
Visibly reduces fine lines and wrinkles. Promotes collagen production with long-term use. 91% reported visible skin resurfacing in clinical trials.
Results timeline
MONTH 2-3+Immediate Glow & Smoothness
Skin looks noticeably brighter and feels smoother upon waking. Many users report a visible luminosity and plumped skin from the very first application.
85% noticed immediate glowImproved Texture & Tone
Surface roughness begins to smooth out. Skin tone starts to look more even. Some users may experience mild dryness initially as dead skin is shed.
91% noticed smoother textureVisible Decongestion & Brightening
Pores appear minimized and congestion is visibly reduced. Hyperpigmentation and dark spots begin to fade. Overall skin luminosity is significantly improved.
97% agreed skin was smootherFine Line Reduction & Collagen Boost
With consistent twice-weekly use, fine lines and wrinkles become less noticeable. Collagen stimulation from glycolic acid leads to firmer, more resilient skin over time.
95% reported brighter, illuminated skinRatings by platform
930+ REVIEWSPros & cons
BALANCEDPraised
- Immediate visible glow and smoothness after first use
- Time-release technology minimizes irritation and redness
- Short, clean ingredient list (only 17 ingredients)
- Non-drying formula that doesn't compromise the skin barrier
- Works beautifully alongside retinal products
- Fragrance-free with no artificial colours
- B Corp certified, vegan, and cruelty-free brand
- Manufactured in Medik8's own ISO-certified UK lab
Criticized
- Small bottle (30ml) for a premium price ($49)
- Not suitable for very sensitive or rosacea-prone skin
- Not fungal acne (malassezia) safe
- Limited to 2-3 times per week use only
- Requires strict daily SPF commitment
- Overuse can damage the skin barrier (not for nightly use)
- Results on deeper pigmentation take 2+ months
Budget-friendly alternatives (dupes)
DUPES
Much higher AHA concentration (30% vs 10%) but a wash-off 10-minute mask, not a leave-on overnight treatment. No time-release technology — significantly more irritating. Best for experienced acid users only.
Contains 5% glycolic + lactic acid blend (lower strength). Added ceramides for barrier support. Daily use formula. Larger 1.7 oz bottle. Good for beginners but less potent results than Medik8's 10% encapsulated formula.
8% glycolic acid in a gel formula (vs 10% milky serum). Daily use product without time-release technology. Includes green tea and chamomile for soothing. Larger 3.3 oz bottle but lower concentration and no encapsulation.
Comparison with competitors
SIDE-BY-SIDE
Storage & shelf life
12 MONTHS12 months after opening
Store in a cool, dry place away from direct sunlight and heat. Keep away from naked flames or direct heat sources.
Opaque squeeze tube with screw cap, protecting the formula from light and air degradation.
Yes — 30ml is well under the 100ml carry-on liquid limit for air travel.
Frequently asked questions
FAQMedik8 advises consulting your doctor or obstetrician before using Sleep Glycolic during pregnancy or breastfeeding. While glycolic acid is generally considered lower-risk than retinoids, the 10% concentration is potent and professional guidance is recommended. The brand itself states they cannot provide product advice in relation to medical conditions such as pregnancy.
No. Sleep Glycolic contains Polysorbate 60, Caprylic/Capric Triglyceride, and Sorbitan Isostearate — all of which can potentially feed malassezia yeast and trigger or worsen fungal acne. If you are prone to fungal acne, consider a simpler glycolic acid formula without these emulsifiers and fatty acid esters.
Yes, Sleep Glycolic can be used alongside vitamin A products (like Medik8 Crystal Retinal) once your skin has fully adjusted to the retinal. However, do not use other leave-on acid products (AHA toners, BHA serums) in the same routine as Sleep Glycolic. Use them on alternate nights instead. Vitamin C serums are best reserved for the morning routine on the days following Sleep Glycolic use.
Sleep Glycolic is best suited for normal, oily, combination, and mature skin types. It excels at addressing dullness, uneven texture, congestion, and signs of ageing. Medik8 does not recommend it for very sensitive skin. Those with dry skin can use it successfully when paired with a rich night moisturizer on top.
Most users notice an immediate glow and smoother texture after the very first use. Visible improvements in skin tone, congestion, and texture are typically seen within 2-4 weeks of consistent use (2-3 times per week). Deeper concerns like fine lines, wrinkles, and hyperpigmentation may take 6-12 weeks of regular use to show significant improvement.
Sleep Glycolic is a direct acid and should be the first product you apply after cleansing in the evening. Layer all other serums (retinal, peptides, hyaluronic acid) and your night moisturizer on top. Use it 2-3 times per week only, not every night. Always follow with SPF 30+ the next morning.
Sleep Glycolic has a low comedogenic rating of 1 out of 5. The lightweight milky serum formula is very unlikely to clog pores. In fact, glycolic acid itself works to decongest pores by dissolving the bonds between dead skin cells, helping to prevent and clear blockages.
Sleep Glycolic has a Period After Opening (PAO) of 12 months. At the recommended usage of 2-3 times per week with a pea-sized amount each time, the 30ml tube typically lasts approximately 3-4 months. Store in a cool, dry place away from direct sunlight for best results.
Verdict: Medik8 Sleep Glycolic is one of the most intelligently formulated at-home glycolic acid peels available. The crystal encapsulation time-release technology genuinely sets it apart from competitors, delivering potent 10% glycolic acid results while keeping irritation remarkably low. It works brilliantly for dull, congested, or ageing skin — with visible results from the very first use. The short ingredient list (just 17 ingredients), fragrance-free formula, and B Corp-certified brand ethos make it a premium choice you can feel good about. The only drawbacks are the small 30ml size for $49, the fact that it is not fungal acne safe, and it is not suitable for very sensitive skin. For everyone else seeking professional-grade AHA exfoliation at home, this is an outstanding investment.
Product Overview
What are Quick Product Notes?
Quick product notes are a great way to check if a product is free from commonly avoided ingredients by skincare enthusiasts. These preferences come about for different reasons depending on the ingredient such as personal experiences, sensitivities, health preferences & etc.
Pro Tip Alert!
Just because a product is not free from a common preference does not mean it's a bad product! You can make a personal decision whether or not you want to use a product that contains these ingredients or not - click the labels of the preference to read more about them.
Quick Product Notes
Paraben-Free
Paraben-Free
Understanding Parabens
Parabens are a large group of preservatives which are used to prevent bacteria growing in cosmetic formulations. There has been some healthy controversy surrounding them due to a few studies finding paraben presence in breast tumours and breast tissue. However, the majority of the scientific community have deemed these findings non-conclusive due to the limitations of these studies. There's still a lot of support for avoiding parabens following the better safe than sorry route. If you do we completely support you! If you are concerned about the health safety of parabens, then feel free to avoid them by looking out for the Paraben-Free icon. If not, don't worry about it - they do have had one of the longest safety records as preservatives!
Which Ingredients are classified as Paraben?
A product will be paraben-free if it does not contain any of the following parabens:
- Sodium Isobutylparaben
- Sodium Ethylparaben
- Sodium Butylparaben
- Propylparaben
- Isopropylparaben
- Isobutylparaben
- Sodium Propylparaben
- Butylparaben
- Ethylparaben
- Sodium Methylparaben
- Methylparaben
Sulfate-Free
Sulfate-Free
Understanding Sulfates
Sulfates are a large group of ingredients which act as cleansing agents in Cosmetics. They help loosen up the dirt and grime from your skin and hair to allow for water to wash it away with ease. However some sulfates are so good at their job, they can wash off your skin’s own natural oils that keep it moisturised and protected which can lead to dryness and irritation. Most people will find no issues with sulfate, however if you find your skin doesn't like sulfates then free feel to avoid them by looking out for the sulfate-free icon on Skincarisma.
Which ingredients are classified as sulfates?
We've taken the Sulfates which are considered more harsh for our Sulfate-Free status. A product will be Sulfate-Free if it does not contain any of the following Sulfates:
- TEA-Dodecylbenzenesulfonate
- Ammonium Laureth Sulfate
- Sodium Lauryl Sulfate
- PEG-15 Cocamine
- Sodium Laureth Sulfate
- Sodium Cocoyl Sarcosinate
- Sodium C14-16 Olefin Sulfonate
- Dioctyl Sodium Sulfosuccinate
- Ammonium Xylenesulfonate
- Ammonium Lauryl Sulfate
- Sodium Xylenesulfonate
- Sodium Myreth Sulfate
- Sodium Lauryl Sulfoacetate
Alcohol-Free
Alcohol-Free
Understanding Simple Alcohols
Alcohol ingredients are widely used in cosmetics and come in different types. For the most part alcohols are not problematic at all. However one type of alcohols, simple alcohols can be quite drying to the skin because it evaporates very quickly. This can cause irritation which can also lead to other skin complications. These alcohols should never be used alone on your skin, but combined with other cosmetic ingredients, they are normally without issue. However, for some people with sensitive and easily irritable skin, avoiding products with these simple alcohols may be beneficial. If you find your skin doesn't like these simple alcohols, then free feel to avoid them by looking out for the Alcohol-Free icon.
Which Ingredients are classified as Alcohol?
A product will be alcohol-free if it does not contain any of the following alcohol ingredients:
- SD Alcohol
- Alcohol Denat
- Isopropyl Alcohol
- Alcohol
Silicone-Free
Silicone-Free
Understanding Silicones
If you've ever used a skincare, makeup or beauty product that's made your skin look and feel smoother tempoarily - it's likely contained Silicone. They are a popular class of ingredients found in cosmetics due to their smooth, soft, easy-to-spread and smooth properties that help creates an artificial layer/barrier on top of skin or hair (commonly found in conditioners).
For the same reasons they are popularly used, they are also commonly avoided. Anecdotally, many individuals have reported that Silicones cause/excerbate breakouts, irritation, cause a feeling of skin being unable to breathe, cause clumping of cosmetic products and find it difficult to wash off. As a result, those who find them problematic are avoiding them and increasingly, cosmetic companies are avoiding them as well.
If you have had bad experiences with Silicones in the past, or suspect they are problematic then look out for the tick on the Silicone-free label.
Disclaimer
The Silicone-free label only includes the most common Silicone ingredients that have indentified been reported by individuals that could potentially cause issues.
These include: Amodimethicone, Behenoxy Dimethicone, Bis-Aminopropyl Dimethicone, Cetearyl Methicone, Cetyl Dimethicone, Cyclomethicone, Cyclopentasiloxane, Dimethicone, Dimethicone Copolyol, Dimethiconol, Methicone, Phenyl Trimethicone, Phenyl Trimethicone, Stearoxy Dimethicone, Stearyl Dimethicone, Trimethylsilylamodimethicone.
Note, that this does not include all ingredients part of the Silicone class of ingredients.
EU Allergen-Free
EU Allergen-Free
Understanding the Identified Contact Allergens
The EU's Scientific Committee on Consumer Safety (SCCS) has identified and established 26 cosmetic ingredients that are likely contact allergens (potential to cause skin allergies) as demonstrated in clinical or epidemiological studies. The EU's SCCS have recommend cosmetic companies to disclose them on the labels if used and in cases where the concentration exceeds 0.001% in leave-on products and 0.01% in rinse-off products, then they must be labelled.
Look out for the tick on the EU-Allergen free label to know your cosmetic is free from any of the 26 identified cosmetic ingredients.
For more information regarding the EU's Scientific Committee on Consumer Safety, please visit their official website.
Disclaimer
The EU Allergen Free label is for the 26 ingredients identified by the EU SCCS and products will be only flagged if a suspected ingredient is on it's ingredient list. It is possible for cosmetics to contain one of the suspect ingredients without it appearing on the ingredient list due to it not reaching the concentration threshold to disclose it and cosmetic manufacturers choice to not disclose it.
Also note, the EU Allergen Free label is not personalized for your own allergies you may have and it does not constitute as medical advice. For your specific case, always consult your medical professiona such as dermatologist, physician, pharmacist, or health care provider - please read our medical disclaimer for more information.
Fungal Acne (Molassezia) Safe
Fungal Acne (Molassezia) Safe
Understanding Fungal Acne (Pityrosporum Folliculitis/Malassezia Folliculitis)
Pityrosporum Folliculitis/Malassezia folliculitis or simply known as Fungal Acne is a persistent acne-like condition that commonly responds poorly to traditional acne-treating methods. Unlike most cases of Acne where bacteria is the culprit, Fungi is the culprit of Fungal Acne (Hence the name!). There are certain classes & groups of ingredients that have been shown to promote and feed the growth of the Fungal Acne, Fungi such as fatty acids, oils, esters, polysorbates and fermented ingredients.
For more information regarding Fungal Acne, please visit Simple Skincare Science (f.c) - #3 of our Recommend Skincare Resources for an amazing comprehensive guide!
Please Read: How to use the Fungal Acne (Malassezia) Label
At SkinCarisma, we've done our best to identify as many ingredients as possible but note the fungal-free label may not be 100% accurate due to the complexconditions and combination of ingredients that malezzeria can thrive on.
Additionally, products that may contain ingredients that have shown to feed Malassezia may not neccessarily exacerbate the condition due to concentration of ingredient used in the product, this information is simply not available on the products.
As a result, please note this is only an experimental label that can be best used to possible identify problematic products you have used in the past. It is in no way a perfect identifier nor a predictor in whether or not it will exacerbate or cause fungal acne. It will continue to be worked on as more information and research comes to light.
If you find any ingredients you believe should be included, please email us at snails@skincarisma.com.
Disclaimer
Due to the lack of substantial research into this area it is very likely there are other ingredients and class/groups of ingredients that could feed Fungal Acne which have not been indentified.
The Fungal-Safe label does not constitute as medical advice. For your specific case, always consult your medical professiona such as dermatologist, physician, pharmacist, or health care provider - please read our medical disclaimer for more information.
What are Notable Effects & Ingredients?
Ever used a product that promised a certain effect but provided no results? It might not have contained any notable ingredients that could have been responsible for that promised effect. It doesn't matter what the marketing or packaging «promises» it can do, if it doesn't contain anything that can help - then the likelihood of it helping is low.
We help you identify key notable ingredients that have been shown to help with effects such as acne-fighting, brightening, UV-protection, wound healing & anti-aging to help you achieve your skincare goals smarter. Please note that different notable ingredients have varying levels of research behind them, some are extremely well proven yet some have mixed research in their efficacy.
Pro Tip Alert!
Just because a product doesn't contain any notable ingredients doesn't mean it's bad. And a product with notable ingredients (or even many) doesn't necessarily guarantee the efficacy of the product performing these effects either. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine this.
Be smart and use this as just a starting point for you to make more informed and smarter choices and compare it with reviews to see if the product is right for you
Notable Effects & Ingredients
Anti-Aging from 1 ingredient(s):
Brightening from 2 ingredient(s):
Promotes Wound Healing from 2 ingredient(s):
Ache-fighting from 1 ingredient(s):
What are Ingredients Related to Skin Type?
Why are some products great for some people and horrible for others? Well everyone has different skin types and different reactions to the same ingredients.
We've identified a range of ingredients that are commonly regarded as potentially good or bad for those with Dry, Oily/Acne-Prone or Sensitive skin.
Pro Tip Alert!
A product that contains good or bad ingredients for your skin type doesn't always flat out make the entire product good or bad for your skin. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine your skins reaction.
One of the best ways to use this section is to troubleshoot products you've had bad experiences with in the past. Check if it contains any of the marked ingredients to point out suspect ingredients to avoid in the future!
Ingredients Related to Skin Types
Dry Skin
Oily/Acne-Prone Skin
Sensitive Skin
What is the Ingredient Safety Breakdown?
Ingredient Safety Breakdown refers to the percentage % of ingredients in different risk categories as classified by EWG (Environment Working Group) if they are available. There are almost endless cosmetic ingredients and they are one of the few organisations globally that have assigned ratings to a lot of the more commonly used ingredients which is why we reference them.
Pro Tip Alert!
EWG is seen by many to be more on the alarmist side in their assignment of health ratings resulting in rating ingredients as riskier than they actually are. We recommend using this a reference point rather than a strict guide of ingredient safety and to always do further research if into ingredients that you may find suspect.
Ingredient Safety Breakdown
Product ingredient list
| EWG | CIR | Ingredient Name & Cosmetic Functions | Notes |
|---|---|---|---|
| 1 |
Water
Solvent, Skin Conditioning
|
|
|
| 4 |
Glycolic Acid
Ph Adjuster, Buffering Agent, Exfoliant, Exfoliating, Buffering
|
Brightening
Ache-fighting
Anti-Aging
Promotes Wound Healing
Dark Spots
Texture
Pores
|
|
| 1 |
Cyclodextrin
Chelating Agent, Absorbent
|
|
|
| 1 |
Caprylic/Capric Triglyceride
Solvent, Skin Conditioning, Masking, Perfuming, Emollient
|
|
|
| 3 |
Dimethicone
Skin Conditioning, Emollient, Antifoaming Agent, Skin Protecting
|
|