Klira Skin Size 08
A prescription with 6 ingredients, including retinoid and hyaluronic acid.
Prescription with 6 ingredients that contains hyaluronic acid and retinoid
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Key Ingredients
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Ingredients Explained
Tretinoin (aka retinoic acid) is the gold standard retinoid in dermatology because it's the form of vitamin A that your skin can use right away. It's a prescription drug and regulated as medication in most countries.
Unlike retinol, it skips the conversion steps and goes straight to work.
Inside your skin cells, it binds to receptors called retinoic acid receptors and switches on the genes that control how skin cells behave.
For acne, it helps your skin shed dead cells properly instead of letting them build up and clog your pores (this is what turns into blackheads and pimples). It also calms redness/swelling, which is why it's a FDA-approved acne treatment.
Tretinoin also tells your skin to make more collagen and slows down the stuff that breaks collagen apart too. Over time, your skin looks smoother, softer, and more even, with fewer lines lines and sun spots.
The evidence for this ingredient is strong:
A systematic review of randomized controlled trials found that topical tretinoin consistently improved wrinkles, pigmentation, sallowness, and dark spots. Results typically showed up as early as one month and lasted out to 24 months.
All studies also found this ingredient to be safe and well-tolerated.
Typical concentrations run from about 0.01-0.1%, with 0.025%-0.1% being the usual range studied for photoaging and a 0.05% cream producing measurable wrinkle/roughness improvements in large six-month trials.
The main trade-off is irritation; dryness, peeling, redness, and sun sensitivity are common in the first few weeks so be sure to pair it well with a good moisturizer and daily sunscreen.
Learn about a form of retinoid you can purchase at the store, retinol.
Learn more about TretinoinAloe Barbadensis Leaf Juice is the filtered, stabilized liquid pressed from the inner gel of the aloe vera leaf.
In cosmetics, it shows up as either soothing active or a water-replacement base. It is roughly 98-99% water and the last 1-2% is an interesting mix of polysaccharides, amino acids, vitamins, minerals, and enzymes.
The polysaccharides do most of the work: they bind water at the skin surface for a light, non-greasy hydration boost. And one of the polysaccharides, glycomannan, is linked to fibroblast stimulation + collagen synthesis. This is also why aloe has such a long track record in wound and burn healing.
This ingredient is also calming with anti-inflammatory and mild antimicrobial activity, making it a great pick for sensitive, irritated, or post-sun skin.
Realistic expectations matter though; the solid evidence is mostly limited to hydration, soothing, and wound support. Deeper claims about anti-aging or sun protection are not well backed, and science reviews note it does not prevent radiation-induced skin injury.
Because it plays well with almost everything, it's commonly used as a base alongside other actives like niacinamide or vitamin C.
Typical usage concentrations range from 0.5% (where hydration benefits already show up) all the way to 90%+ (where it replaces water as the main base).
The safety for this ingredient is well-establish as well. Overall, this is a great supporting ingredient for those who want a boost in hydration.
Learn more about Aloe Barbadensis Leaf JuiceHyaluronic acid (HA) is a glycosaminoglycan (basically a long sugar chain) that your skin already makes on its own. In your skin, HA lives in the extracellular matrix and acts as the body's moisture reservoir.
Topically, HA is a humectant that binds water and helps skin look more plump, smooth, and hydrated.
The only catch is that HA isn't a single thing; it actually comes in a wide range of molecular weights (~50 - 2,000+ kDA) and size matters.
Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.
This is why the best HA serums blend the two sizes together so you get the best of both worlds.
The majority of cosmetic HA is produced by bacterial fermentation, typically using Streptococcus or Bacillus strains. Typical use levels in skincare sit around 0.1-2%.
A clinical study using a 0.2% low-molecular weight HA gel showed improvement in facial seborrheic dermatitis with excellent tolerance.
These are some other common types of Hyaluronic Acid:
Learn more about Hyaluronic AcidHydrolyzed Collagen is Collagen (usually sourced from fish, bovine, or porcine byproducts) that's been broken down into smaller peptides. This makes it water-soluble and easy to blend into formulations.
In a formula, it works mainly as a skin-conditioning and moisturizing agent.
The small peptides and amino acids (including Natural Moisturizing Factor components like Hydroxyproline, Serine, and Aspartic Acid) help the surface of the skin hold onto water, feel softer, and look temporarily plumper.
This ingredient also has mild film-forming and antioxidant properties with research showing the antioxidant effect is stronger the lower the molecular weight of the peptides.
It's worth being realistic here:
Topically applied Hydrolyzed Collagen conditions the upper layers of skin rather than rebuilding the structural collagen deep in your dermis (the wrinkle-and-firmness benefits people associate with Collagen mostly come from oral supplements in studies, not topicals).
However, recent lab and skin-model work on Hydrolyzed Fish Collagen has shown promising effects on cell viability and wound healing when used as an active.
Typical concentrations range from 0.2-2%, but the percentage can go much higher in rinse-off or hair products (sometimes even above 50%).
Clinical studies on this ingredient showed no irritation, sensitization, or phototoxicity.
If you are looking for vegan collagen, it usually goes by a different INCI name like hydrolyzed soy protein. Vegan collagen is derived from yeast, bacteria, or plant sources.
The results are varied.
A study from 2021 found hydrolyzed collagen increased elasticity and improved wrinkles in 1,125 participants between age 20 and 70. Another study found increased skin thickness in participants between the ages of 45 to 59.
However, It is difficult to prove that oral collagen will end up working on your skin. Many of the studies using hydrolyzed collagen also add several vitamins and nutrients into the test mixture as well.
Further studies are needed at this time.
Learn more about Hydrolyzed CollagenCaprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.
Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.
In practice, that translates to a long shelf life and a consistently elegant skin feel.
While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.
Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.
Learn more about Caprylic/Capric TriglycerideCholesterol is a lipid that is naturally found in human skin and is one of the three key components of your skin barrier. In skincare, it is an emollient and barrier-repairing ingredient.
It works by fitting directly into the lipid layers of skin to help restore structure and reduce transepidermal water loss (TEWL).
This is a great ingredient for dry, compromised, or aging skin; our skin starts to produce less cholesterol with age.
Research shows cholesterol works best in combination with ceramides and fatty acids, the other two major components in your skin barrier.
Cholesterol is also a well-establish penetration enhancer and can help other actives absorb more effectively.
Cosmetic-grade cholesterol is usually derived from lanolin but plant and synthetic options also exist. We recommend reaching out to the brand if you have questions about their source of cholesterol.
Learn more about CholesterolReviews
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Where it's from
Klira is a British brand
We're dedicated to providing you with the most up-to-date and science-backed ingredient info out there.
The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Updated January 8, 2026 • Added by shazs