CERAMIDE AP

Ceramide AP is a phytoceramide in which the ceramide N-acyl group is specified as 2-hydroxyoctadecanoyl
Ceramide AP is a cosmos approved, skin identical ceramide AP also referred to as ceramide 6 in the old nomenclature. 
Ceramide APs ability to form a hair pin structure within the lipid lamellar structure of the stratum corneum, provides stable retention of water. 

CAS Number: 212070-45-6
Molecular Formula: C36H73NO5
Molecular Weight: 599.97

Synonyms:Ceramide AP, ceramide 6, Ceramide VI, Cytomide VI, Biomide 6, Ceramide 6 II, N-2-Hydroxystearoyl-phytosphingosine, F1X8L2B00J, phytosphingosine-2-hydroxy-18:0, 212070-45-6, N-(2-hydroxyoctadecanoyl)phytoceramide, PHC-C 18:0/18:0, N-(2-hydroxyoctadecanoyl)phytosphingosine, alpha-Hydroxystearoyl-4-hydroxysphinganine, alpha-Hydroxystearoyl-C18-phytosphingosine, Octadecanamide, N-((1S,2S,3R)-2,3-dihydroxy-1-(hydroxymethyl)heptadecyl)-2-hydroxy-, 2-(2'-hydroxyoctadecanoylamino)-1,3,4-octadecanetriol, RefChem:575145, N-(alpha-hydroxyoctadecanoyl)phytosphingosine, N-(2-hydroxyoctadecanoyl)-hydroxysphinganine, N-(2-hydroxyoctadecanoyl)-4R-hydroxysphinganine, Cer(t18:0/18:0(2OH)), N-(2-hydroxyoctadecanoyl)-4-hydroxysphinganine, Ceramide AP [INCI], DL-CER6, Ceramide 6 II [INCI], UNII-F1X8L2B00J, SCHEMBL4133281, CHEBI:67041, BBAFBDLICMHBNU-MFZOPHKMSA-N, LMSP02030016, DB14705, N-(2-hydroxyoctadecanoyl)-phytosphingosine, phytosphingosine-2-hydroxy-18:0, ceramide, N-(2-(R,S)-hydroxyoctadecanoyl) phytosphingosine, .ALPHA.-HYDROXYSTEAROYL-4-HYDROXYSPHINGANINE, .ALPHA.-HYDROXYSTEAROYL-C18-PHYTOSPHINGOSINE, Q27135599, 2-hydroxy-N-[(2S,3S,4R)-1,3,4-trihydroxyoctadecan-2-yl]octadecanamide, PubChem, Octadecanamide, N-[(1S,2S,3R)-2,3-dihydroxy-1-(hydroxymethyl)heptadecyl]-2-hydroxy-, Ceramide AP, Water soluble Ceramide VI, ViableCare Ceramide AP, Sphingomyelin Impurity 8 (Ceramide VI), Octadecanamide,?N-[(1S,2S,3R)-2,3-dihydroxy-1-(hydroxymethyl)heptadecyl]-2-hydroxy- Octadecanamide,?N-[(1S,2S,3R)-2,3-dihydroxy-1-(hydroxymethyl)heptadecyl]-2-hydroxy-, 2-hydroxy-N-((2S,3S,4R)-1,3,4-trihydroxyoctadecan-2-yl)octadecanamide, Sphingomyelin Impurity 10

Ceramide AP stands for α-hydroxy-N-stearoylphytosphingosine) belongs to a larger group of ceramides that are naturally occurring, long chains of lipids (fats) in the skin. 
To put it into perspective, the skin’s general composition of ceramides is around 50%; of that, 16% of those ceramides are of the AP variety. 
Ceramide APs are sphingolipids that contain a sphingoid moiety (which can be sphingosine (S), dihydrosphingosine (D), phytosphingosine (P) or 6-hydroxy-sphingosine (H)), linked with a long-chain FFA moiety (which can be nonhydroxy (N), α-hydroxy (A) or ester-linked ω-hydroxy (EO)) through an amide bond. 

Research indicated that CER [AP], with four hydroxyl groups on its head group, can form super stable membranes through strong hydrogen bonds. 
Ceramide AP has also been shown to be antiproliferative and proapoptotic in numerous cancer cell types in vitro. 
Therefore, administration of Ceramide AP to the skin might help to restore the barrier function of aged and affected skin.

Ceramide AP belongs to the ceramide family and is an important lipid. 
Formed by sphingosine and fatty acids linked by an amide bond, it appears as white to light - yellow powder or waxy solid. 
Abundant in the skin's stratum corneum, it interacts with other lipids to build and maintain the skin barrier, thus widely used in cosmetics.

Ceramide AP, also known as Ceramide 6, Ceramide VI, or N-(2-hydroxyoctadecanoyl)phytosphingosine, is a member of the naturally occurring ceramide family that plays a vital role in maintaining the structure and function of the skin barrier. 
Ceramide AP is classified as a 2-hydroxy ceramide, meaning its fatty acid chain has a hydroxyl group, which gives it unique properties compared to other ceramides such as Ceramide 1, 2, or 3.

This molecule is found naturally in the stratum corneum, the outermost layer of the epidermis, where it combines with cholesterol and free fatty acids to form a strong and stable lipid matrix. 
The presence of Ceramide AP is essential because it helps create the “mortar” that binds together the “bricks” (corneocytes), which together form the skin’s protective barrier. 
This barrier prevents excessive water loss (transepidermal water loss, TEWL) and defends against environmental aggressors such as pollutants, allergens, and pathogens.

In skincare and dermatological formulations, Ceramide AP is widely used as a moisturizing and barrier-repair ingredient. 
Its chemical structure allows it to mimic the body’s own natural ceramides and integrate seamlessly into the skin, making it especially effective in products formulated for dry, sensitive, or compromised skin conditions such as eczema, atopic dermatitis, and psoriasis. 
By replenishing depleted lipid levels, Ceramide AP improves hydration, elasticity, and softness, while also reducing irritation and restoring comfort.

Ceramide AP are a sub-group of the lipids. 
The human skin contains ceramides above all in the horn cells of the epidermis. 
They form a natural barrier which protects the skin from desiccation and avoids the penetration of contaminants and irritants.

When used alongside ceramide NP, the association of the two ceramides promotes a tighter structure and consequently stronger skin barrier
Ceramide AP is a skin conditioning agent. 
Its ability to form a hair pin structure within the lipid lamellar structure of the stratum corneum, provides stable retention of water. 

When used alongside ceramide NP, the association of the two ceramides promotes a tighter structure and consequently stronger skin barrier.
It offers anti-aging, hydrating, moisturizing, nourishing, calming, soothing, redness, elasticity and flexibility benefits.
Ceramide AP is an oil soluble complex of Ceramide 1, Ceramide 2, Ceramide 3, Ceramide 4 and Ceramide 6 present in human skin. 

Ceramide AP is the main component of the stratum corneum of the epidermis layer of human skin. 
Together with cholesterol and saturated fatty acids, ceramide creates a water-impermeable, protective organ to prevent excessive water loss due to evaporation as well as a barrier against the entry of microorganisms.

Ceramide AP helps to repair the skin barrier function, improve skin hydration and reduce TEWL. 
Ceramide AP is also effective for improving hair hydrophobicity and smoothness

Boiling point: 748.3±60.0 °C(Predicted)
Density: 0.967±0.06 g/cm3(Predicted)
pka: 13.26±0.20(Predicted)
InChIKey: BBAFBDLICMHBNU-MFZOPHKMSA-N
SMILES: C(N[C@@H](CO)[C@H](O)[C@H](O)CCCCCCCCCCCCCC)(=O)C(O)CCCCCCCCCCCCCCCC

Ceramide AP is also valued in anti-aging products, since natural ceramide production declines with age, leading to roughness, fine lines, and a weakened barrier. 
By reinforcing the skin’s lipid structure, Ceramide AP helps to restore youthful smoothness and resilience, preventing premature signs of aging caused by dehydration and external stress.
Beyond skincare, Ceramide AP is sometimes incorporated into hair care formulations like shampoos, conditioners, and repair masks. 

In this context, it helps to coat and protect the hair shaft, reduce breakage, smooth frizz, and improve resistance to chemical or heat damage by strengthening the lipid layer around the cuticle.
Ceramide AP is also valued in cosmetic anti-aging treatments, where it acts synergistically with other ceramides, cholesterol, and fatty acids to mimic the skin’s natural lipid “mortar.” 
When applied consistently, it helps plump the skin, smooth fine lines, and improve elasticity, making it an important active ingredient in high-performance moisturizers, serums, and night creams. 

Because it restores the skin’s water-retaining capacity, it prevents the chronic dehydration that accelerates visible aging.
Naturally occurring in the skin, Ceramide AP, also known as ceramide 1, is part of the extracellular matrix that consists mainly of lipids; these waxy molecules are found between the skin cells, resulting in them playing a vital role in keeping the skin surface healthy and hydrated. 

Over 340 specific species of ceramides were found, and ceramide EOP was the first to show decreased levels of ceramides to weaken the barrier, making skin more vulnerable to external stressors. 
More specifically, a decline in Ceramide AP has been linked to skin conditions such as eczema and psoriasis. 
Topical application of ceramide AP via skin care formulas can help fill this gap and strengthen the skin’s barrier against external stimuli.

Generally, ceramides work best when combined with other replenishing ingredients like fatty acids and cholesterol. 
These lipid mixtures work in multiple ways to improve skin’s hydration, texture, and suppleness. 
Ceramide AP within the skin also play a vital role in maintaining skin health since they signal other processes that keep things orderly.

Ceramide AP is considered a biocompatible, non-toxic, and safe ingredient that has become a cornerstone in modern cosmetic science. 
Its ability to replicate and reinforce the skin’s natural lipids makes it a highly effective component in formulations aimed at moisturizing, barrier repair, soothing sensitive skin, and preventing premature aging.
Ceramide AP is a skin-identical lipid molecule that belongs to the alpha-hydroxyceramide subclass, which makes it structurally distinct from many other ceramides found in the skin. 

Its hydroxylated fatty acid side chain gives it slightly different chemical behavior, including the ability to interact more efficiently with water molecules, which enhances its role in maintaining optimal skin hydration. 
This subtle but important structural variation means that Ceramide AP not only reinforces the lipid barrier but also contributes directly to the water-binding capacity of the stratum corneum.

From a biological perspective, Ceramide AP is deeply involved in skin homeostasis and renewal. 
Ceramide AP participates in regulating the differentiation of keratinocytes into corneocytes, which are the building blocks of the outer skin barrier. 
By supporting this process, Ceramide AP helps maintain a healthy cycle of skin shedding and renewal, ensuring that the barrier remains strong, flexible, and resistant to external stressors.

In dermatological science, Ceramide AP has been studied for its benefits in barrier-deficient skin disorders, particularly atopic dermatitis and xerosis (extremely dry skin). 
Patients with these conditions often show reduced levels of alpha-hydroxyceramides, which contributes to barrier dysfunction. 
Topical formulations containing Ceramide AP can replenish these missing lipids, reduce itching, flaking, and inflammation, and provide long-lasting relief compared to standard emollients that only coat the skin surface.

Uses:
One of the most important uses of Ceramide AP is in moisturizing and barrier-repair creams, lotions, and serums, where it helps to restore the lipid balance of the stratum corneum. 
Because Ceramide AP is an alpha-hydroxyceramide, it not only reinforces the structural barrier of the skin but also enhances its ability to retain water, making it especially valuable for individuals with chronically dry or dehydrated skin.

Ceramide AP is also used extensively in dermatological formulations designed for sensitive and compromised skin conditions. 
In patients with eczema, psoriasis, or atopic dermatitis, ceramide levels are often depleted, which leads to excessive water loss and irritation. 
When added to therapeutic ointments or medical moisturizers, Ceramide AP can replenish missing lipids, reduce skin roughness and scaling, and provide long-lasting comfort that goes beyond the temporary effects of conventional emollients.

In the field of anti-aging skincare, Ceramide AP is included in serums, night creams, and restorative treatments because of its ability to smooth fine lines, plump the skin, and improve elasticity. 
Since natural ceramide production declines with age, Ceramide AP helps to compensate for this loss, ensuring that the skin barrier remains resilient and hydrated, thereby slowing the visible signs of aging caused by dehydration and environmental stress.
Another significant use is in post-procedure recovery products that are recommended after cosmetic treatments such as chemical peels, laser resurfacing, or microdermabrasion. 

Because these procedures temporarily disrupt the skin’s barrier, formulations with Ceramide AP speed up repair, reduce discomfort, and protect the skin during its healing phase, allowing patients to recover more comfortably and with fewer complications.
Ceramide AP also has applications in hair care formulations, including shampoos, conditioners, and repair masks, where it strengthens and protects the cuticle layer of the hair shaft. 
By filling gaps in the lipid layer of damaged or chemically treated hair, it improves softness, reduces breakage, minimizes frizz, and restores shine, while also supporting scalp health by reinforcing the skin barrier.

Ceramide AP is further used in lip care products such as balms and treatments, where it prevents chapping and maintains long-lasting hydration in delicate skin areas. 
Because of its strong barrier-repairing properties, it creates a protective film that shields lips from harsh environmental factors like cold weather or wind exposure.
Ceramide AP is utilized in pharmaceutical and cosmeceutical products not only as an active ingredient on its own but also as a supportive component that improves the tolerability of stronger active compounds. 

By stabilizing the skin barrier, it reduces irritation and enhances the absorption of actives such as retinoids, exfoliating acids, or anti-inflammatory agents, making these treatments both safer and more effective.
Ceramide AP is primarily used in advanced moisturizing formulations because of its unique ability to combine water-retention properties with barrier-strengthening effects. 
Unlike simple occlusives that only sit on the surface of the skin, Ceramide AP integrates into the lipid bilayer of the stratum corneum, making it highly effective for long-term hydration and barrier repair. 

This is why many dermatologically tested moisturizers for extremely dry or sensitive skin list Ceramide AP as a core ingredient.
In therapeutic dermatology, Ceramide AP has significant applications in treating atopic dermatitis, eczema, and chronic xerosis. 
These conditions are marked by reduced ceramide levels, which compromise the skin barrier and trigger inflammation. 

By restoring the natural lipid balance, Ceramide AP reduces itchiness, redness, and flaking, while also making the skin more resistant to environmental triggers such as allergens, irritants, and microbes.
This makes it a common component of prescription-strength barrier creams and emollient therapies used by dermatologists.
Ceramide AP is also widely used in anti-aging skincare, especially in serums, overnight masks, and concentrated creams. 

Since natural ceramide production declines steadily with age, mature skin becomes thinner, rougher, and more prone to wrinkles. 
By replenishing this essential lipid, Ceramide AP helps to smooth fine lines, restore elasticity, and enhance firmness, giving the skin a healthier and more youthful appearance. 
Ceramide AP is often combined with cholesterol, fatty acids, and hyaluronic acid in formulations to mimic the skin’s natural repair system.

Another important use of Ceramide AP is in post-procedure care. 
After chemical peels, dermabrasion, or laser treatments, the skin barrier is intentionally disrupted, which makes the skin vulnerable to dehydration, irritation, and infection. 
Products enriched with Ceramide AP are frequently prescribed during the recovery phase because they accelerate healing, strengthen the barrier, and reduce discomfort, allowing patients to recover faster while minimizing potential side effects.

In addition to skincare, Ceramide AP has valuable applications in hair and scalp products. 
In shampoos, conditioners, and hair repair masks, it strengthens the lipid layer around the cuticle, reducing porosity and making hair less fragile. 
This results in shinier, smoother, and more resilient hair, particularly for individuals with chemically processed, bleached, or heat-styled hair. 

On the scalp, Ceramide AP improves barrier function, reduces dryness, and soothes irritation, which helps maintain a healthy foundation for hair growth.
Ceramide AP is also used in lip care formulations, such as lip balms and overnight repair masks, because it provides deep hydration and prevents chapping by creating a protective lipid film. 
This makes it especially useful in extreme climates, where lips are prone to dryness and cracking due to cold winds or high sun exposure.

Another emerging use is in cosmeceutical and pharmaceutical formulations where Ceramide AP acts as both an active and a supportive ingredient. 
By stabilizing the skin barrier, it reduces the irritation potential of strong actives like retinoids, exfoliating acids, or benzoyl peroxide, while at the same time improving their delivery into the skin. 
This makes it an essential addition to complex formulations that need to balance effectiveness with tolerability.

Ceramide AP is a skin-identical molecule, it is increasingly being explored in personalized dermatology and regenerative skincare. 
Scientists are studying how it can be combined with other biomimetic ingredients to create next-generation therapies for barrier repair, not only in cosmetic applications but also in medical contexts such as wound healing, diabetic skin care, and radiation-damaged skin.

Safety Profile:
Ceramide AP is generally regarded as a very safe and biocompatible ingredient, because it is chemically similar or identical to naturally occurring ceramides in the human stratum corneum, which means it is highly compatible with the skin’s own lipid structure and rarely causes toxic effects when used in topical formulations. 
Unlike synthetic chemicals or surfactants that can disrupt the skin barrier, Ceramide AP integrates into the lipid matrix, supporting hydration and barrier function rather than impairing it, and therefore is considered non-irritating for the vast majority of users under normal cosmetic or pharmaceutical use.

From a toxicological perspective, Ceramide AP is essentially non-toxic when applied to intact skin, and it has no significant systemic toxicity because it does not readily penetrate into the bloodstream due to its lipid-based structure. 
Ceramide AP is also not mutagenic, carcinogenic, or teratogenic, which makes it safer than many synthetic active ingredients in personal care products. 
Regulatory bodies such as the European Union Cosmetics Regulation and the U.S. FDA recognize Ceramide AP as safe for inclusion in cosmetic and dermopharmaceutical formulations.

However, although rare, there is a potential for skin irritation or sensitization in individuals with extremely sensitive or allergy-prone skin. 
Some users may experience mild redness, stinging, or itching, particularly if Ceramide AP is formulated with other components such as fragrances, alcohols, or strong preservatives, which can trigger reactions independently of the ceramide itself. 
For this reason, patch testing is sometimes recommended for highly reactive individuals, particularly when using new or highly concentrated formulations.

During industrial or laboratory handling of Ceramide AP in its powdered form, there is a minor risk of mechanical irritation to the skin, eyes, or respiratory tract from dust exposure. 
Protective measures such as gloves, masks, and safety goggles are recommended to prevent inhalation or contact with mucous membranes, even though Ceramide AP is not chemically corrosive.