NOTE: This review has been updated on 01/08/2025 to reflect the new formulation of Medik8 Liquid Peptides. All the information in this review applies to the latest formulation.
Remember the old days when you were lucky to find a small peptide floating alone in a serum? Now, peptide cocktails are all the rage. Blame it on The Ordinary. After they paved the way with Buffet, everyone’s coming out with their own version. About time, too! The latest peptide cocktail to catch my eye is Medik8 Liquid Peptide. It’s a 30% peptide blend said to fight wrinkles and make you look younger. Does it deliver?
What’s In Medik8 Liquid Peptides?
PEPTIDES TO SLOW DOWN AGING
Let’s start with the stars of the show, the peptides. Medik8 Liquid Peptides includes:
- Argirelox: A blend of “Aqua (and) Glycerin (and) Acetyl Hexapeptide-8 (and) Pentapeptide-18 (and) Citric Acid (and) Caprylyl Glycol”. A “Botox-like” peptide that prevents muscles from contracting with full force. Now they can’t move freely, expression lines look less deep. But the only studies confirming this come from the manufacturer (always take them with a pinch of salt).
- Carnosine: A peptide your body already makes on its own, it prevents glycation (corruption of collagen) by blocking sugars from binding to collagen.
- Drone-Targeted Copper Peptide: Copper peptides keep skin in a constant state of repair, making sure everything is working properly. They help skin heal faster, make retinol more tolerable and boost the production of collagen. If your skin’s in good condition, these peptides will just maintain the status quo so you won’t see visible results – but they work. Drone-targeted means these peptides have a GPS that allows them to penetrate the skin enough to reach the collagen-producing cells – but I haven’t found any studies supporting this last claim yet. You’ll find it listed on the label as Copper Palmitoyl Heptapeptide-14 and Heptapeptide-15 Palmitate.
- Matrixyl 3000: A combination of two peptides (palmitoyl tripeptide-1 [formerly known as palmitoyl oligopeptide] + palmitoyl tetrapeptide-7), Matrixyl 3000 is a powerful collagen booster. Most of the studies are done by the manufacturer, but the initial independent research shows it may help treat wrinkles.
- Palmitoyl Tripeptide-5: A collagen-boosting peptide that helps firm and smooth skin over time. It tells your skin to make collagen to keep it bouncy. So far, the only proof it works comes from the manufacturer.
- Tetrapeptide-21: Another anti-aging peptide that helps firm skin and make it feel smoother by boosting collagen and hyaluronic acid production. Again, the only proof it works comes from the manufacturer.
- Palmitoyl Tripeptide-38: Fancy peptide that targets multiple skin layers to improve lines, plumpness, and overall smoothness. The manufacturer claims it can boost the production of 6 main components of your skin barrier (collagen I, III, IV, fibronectin, hyaluronic acid and laminin 5) to reduce wrinkles.
Argirelox aside (let’s face it, NOTHING works as well as Botox!), I’m pretty happy with the mix of peptides Medik8 picked. It’s a varied mix that addresses several causes of aging, getting you covered on all fronts. I just wish we had more research backing up their effectiveness – but the initial results are promising.
Related: What Are The Best Peptides Used In Skincare?
HYALURONIC ACID TO HYDRATE SKIN
Medik8 Liquid Peptides uses Sodium Hyaluronate, a form of hyaluronic acid that’s better able to penetrate your skin.Sodium hyaluronate is a moisture magnet: it attracts moisture from the air and the deeper layers of your skin and dumps it into the surface of your skin. Once there, this extra moisture plumps up fine lines and wrinkles so they look smaller, softens your skin’s texture and brightens up the complexion, giving it a youthful glow.
P.S. Sodium Hyaluronate is so powerful, it can bind up to 1000 times its weight in water!
Related: Why You Should Add Hyaluronic Acid To Your Skincare Routine, No Matter Your Skin Type
Struggling to put together a skincare routine that minimises wrinkles, prevents premature aging, and gives your complexion a youthful glow? Download your FREE “Best Anti-Aging Skincare Routine” to get started (it features product recommendations + right application order):
The Rest Of The Formula & Ingredients
NOTE: The colours indicate the effectiveness of an ingredient. It is ILLEGAL to put toxic and harmful ingredients in skincare products.
- Green: It’s effective, proven to work, and helps the product do the best possible job for your skin.
- Yellow: There’s not much proof it works (at least, yet).
- Red: What is this doing here?!
- Aqua (Water): Literally just the base that everything else is mixed into. Doesn’t do anything special for your skin, but without it, your serum would be a chunky mess.
- Glycerin: Classic hydrating ingredient. It pulls water into your skin like a magnet, so things feel softer and smoother. Super reliable for that bounce.
- Butylene Glycol: Think of this like a sidekick to your moisturisers. It helps other ingredients sink in better and gives your product that silky, spreadable texture.
- Inulin: A prebiotic (yes, like for your gut but for your face). It feeds the good bacteria on your skin and helps keep your barrier happy.
- Panthenol: A form of vitamin B5 that’s basically a big hug for irritated skin. Calms, soothes, and adds hydration.
- Alpha-Glucan Oligosaccharide: Another skin prebiotic. It helps the good bacteria thrive and makes it harder for the bad guys (aka irritants) to mess with your skin.
- Carbomer: Doesn’t do anything for your skin, but it makes the product feel nice and gel-like. Without it, your serum would be watery and weird.
- Polysorbate 20: Basically the glue that keeps oil and water from separating in your product. Not exciting, but important.
- Caprylyl Glycol: Helps keep your skin hydrated and the formula fresh. It also has some light antimicrobial properties, which is a bonus.
- Phenoxyethanol: Preservative that stops your serum from turning into a bacteria soup. Can be irritating if you’ve got sensitive skin or if there’s a lot of it.
- Hydroxypropyl Cyclodextrin: Think of this like a carrier. It holds onto active ingredients and releases them more slowly so your skin can actually use them.
- Dunaliella Salina (Green Algae) Extract: A fancy algae loaded with antioxidants, especially beta-carotene (which your body can turn into vitamin A). Helps fight dullness and protects against stress.
- Ethylhexylglycerin: Another preservative helper that also softens skin a bit. Some people get reactions from it, especially if their skin’s already irritated.
- Citric Acid: Controls the pH of the product so it doesn’t go off. Can lightly exfoliate too, but it might sting if your skin’s raw or you’ve overdone the actives.
- Sodium Benzoate: Preservative that keeps mold and bacteria out. Safe in small amounts, but for some people it can trigger irritation or allergies.
- Pantolactone: Moisturising agent that works like a backup singer for panthenol (vitamin B5). Helps keep hydration locked in.
- Glyceryl Caprylate: Moisturises and helps prevent the product from going bad. Also gives the formula a smoother feel.
- Lactic Acid/Glycolic Acid Copolymer: A combo of two exfoliating acids that smooth out texture and brighten skin. Can make your skin more sensitive to sunlight and sting if overused.
- Polyvinyl Alcohol: Film-forming ingredient often used in peel-off masks or to help products dry down. Over time, it can be drying if it’s overused.
- Phenylpropanol: Solvent and fragrance ingredient that helps preserve the formula. It can irritate skin for some people, especially those sensitive to scents.
- Potassium Sorbate: Another preservative. Mild on its own but may cause irritation for some if used frequently.
- Xanthan Gum: Thickener that gives products that gel-like texture. Doesn’t treat skin, but helps everything feel nice and smooth going on.
Texture
This stuff is liquid. Like, almost water-level runny. It’s not one of those thick, jelly-like serums that feel cushiony going on – this glides across your skin like a dream and sinks in fast. No tackiness, no sticky layer, no pilling under other products. It’s that rare kind of serum you can slap on in a rush and not feel like you’ve coated your face in glue.
Fragrance
It’s fragrance-free. If you’re sensitive to scents or just don’t want your skincare to smell like a department store, this’ll be your jam. There might be a faint whiff of something clinical when you first pump it out (ingredients do have their own smell, after all), but once it’s on your skin? Gone. No fragrance overload, no fake florals.
How To Use It
Just cleanse, pat dry, and press 6 drops into your skin – yes, six. Medik8 is very specific about the dosage. You can use it morning and night, and it plays nicely with everything: retinoids, acids, moisturisers, you name it. If your routine’s already packed, this slides right in without making anything pill or peel. Just don’t rub it like a madwoman – press it in and let it do its thing.
I recommend applying it right before moisturiser, especially if you’re using serums with retinoids, vitamin C or other actives that need to be close to skin to work. Why? These ingredients are proven to work. Peptides not so much… You don’t want to compromise the effectiveness of retinol for something that may work, know what I mean?
Related: Are Copper Peptides More Effective Than Retinol At Fighting Wrinkles?
Packaging
Sleek glass bottle with a dropper that’s built into the pump. It’s giving clinical but cute. The pump dispenses exactly the right amount (which, thank god, because at this price you don’t want to waste a drop). Looks luxe on the shelf, doesn’t leak in your bag, and feels solid in your hand. Very Medik8 – minimal, clean, functional.
Performance & Personal Opinion
The first thing I’ve noticed about Medik8 Liquid Peptides is how soft it makes my skin. It’s so hydrating, it gives my skin that extra moisture boost it needs in this freezing winter weather. But did it do anything for my wrinkles? I’m not sure. I can’t say that it made my fine lines incredibly smaller but – can I tell you a secret? – I didn’t expect it to. Shhh!
It’s not that Medik8 Liquid Peptides doesn’t work. It’s that nothing can get rid of wrinkles in a month. Even retinol, which is more powerful than copper peptides, takes two months to affect collagen production!
But I can tell you this: this serum improved the texture of my skin, making it softer and smoother. It helps protect my skin from the winter cold and soothe irritations. If nothing else, it seems to be keeping the status quo – and that’s something I did expect.
Research on peptides is scant, but promising. I do believe this peptide cocktail can help you fight wrinkles so they look smaller, but you need to play the long game here. Expect to see results, but not straight away.
✅ What I Like About Medik8 Liquid Peptides
- The texture is chef’s kiss. Light, fast-absorbing, non-sticky – perfect for layering without messing up the rest of your routine.
- Fragrance-free without smelling weird. Just does its job and disappears.
- Super hydrating. It leaves your skin feeling plump and soft, especially when the weather’s trying to ruin your face.
- Plays well with strong actives like retinol and vitamin C. No pilling, no drama.
- Packaging is solid, sleek, and practical. That pump-dropper hybrid is weirdly satisfying and stops you from wasting product.
- Long-term potential. Peptides may not be magic, but they are promising, and this formula is stacked with them.
❌ What I Don’t Like About Medik8 Liquid Peptides
- It’s not a quick fix. If you’re expecting to see fewer wrinkles in a month, this isn’t that kind of serum.
- It’s pricey for something that requires patience and consistency. You’ll be halfway through the bottle before you even start to see real changes.
- Peptides don’t have the same strong evidence as retinol, so it’s more of a long-game investment than a proven heavy-hitter.
- If you’re already using multiple serums, this could start to feel like an extra step – not a must-have.
Who Should Use This?
- If your skin’s feeling tight, dry, or just a bit meh – especially in winter – this’ll give it that soft, hydrated bounce without any heaviness.
- If you’re already using retinol, vitamin C, or acids and want something that won’t clash or make your skin freak out, this fits right in.
- If you’ve already nailed the basics and want to slowly build in something anti-aging without going hardcore.
- Basically, if you’re cool with playing the long game and want your skin to feel smoother, calmer, and more “put-together” – this is your kind of serum.
Does Medik8 Liquid Peptides Live Up To Its Claims?
| CLAIM | TRUE? |
|---|---|
| Target the appearance of expression lines and deeper set wrinkles with this hydrating 30% peptide cocktail. | True, but don’t expect extraordinary results in a few weeks. |
| The needle-free formula helps to fight expression wrinkles by minimising muscle contractions while stimulating collagen synthesis. | It has ingredients that have been proven by the manufacturer to do this. |
| Fine lines and wrinkles fade effortlessly away, elasticity is rejuvenated and skin texture is perfectly refined. | It helps with anti-aging, but this claim is totally over the top. NOTHING fades wrinkles effortlessly away. |
Price & Availability
£59.00 at Cult Beauty, Sephora, and SpaceNK
Do You Need It?
It depends. If you’re under 30, you’re still better off with vitamin C and sunscreen. Once you reach the big 3-0, up your game with retinol. If, after that, you still need the extra help in the antiaging department and your wallet won’t feel the hit, that’s when it’s time to add Medik8 Liquid Peptides to your skincare routine.
Aqua (Water), Glycerin, Butylene Glycol, Inulin, Sodium Hyaluronate, Panthenol, Alpha-Glucan Oligosaccharide, Carnosine, Carbomer, Polysorbate 20, Caprylyl Glycol, Phenoxyethanol, Hydroxypropyl Cyclodextrin, Dunaliella Salina (Green Algae) Extract, Ethylhexylglycerin, Citric Acid, Palmitoyl Tripeptide-5, Sodium Benzoate, Acetyl Hexapeptide-8, Tetrapeptide-21, Pentapeptide-18, Palmitoyl Tripeptide-1, Pantolactone, Palmitoyl Tripeptide-38, Palmitoyl Tetrapeptide-7, Glyceryl Caprylate, Lactic Acid/Glycolic Acid Copolymer, Polyvinyl Alcohol, Phenylpropanol, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Potassium Sorbate, Xanthan Gum.
About Gio
Hi, I’m Gio. I’m a no-nonsense, tell-it-like-it-is skin coach and writer on a mission to help you achieve your best skin day ever – every day. I bust skincare myths and debunk marketing jargon to help you figure out what’s worth the splurge and what’s best left on the shelf – using science, not hype. I also offer skincare consultations to help you create the best skincare routine for your unique needs.
