A Singapore Dermatologist Talks: Enhancing Skin Absorption of Cosmeceuticals

by: Dr. Teo Wan Lin

In my previous articles, I have talked about cosmeceuticals and the importance of incorporating them in our daily routines. However, how do we enhance the skin absorption of these cosmeceuticals? Here I will be talking about the limitations of topical formulations and how we can overcome them to ultimately achieve the results that we desire.

The problem with topical formulations for your skin

The outermost layer of the skin, called the stratum corneum, acts as a natural barrier. It prevents foreign material from entering our system, shields us against environmental factors and prevents excessive water loss. The skin is a formidable barrier to the passage of substances into and out of the body, but it can be manipulated to allow it to become a viable pathway for drug administration.

Drug products applied to the skin’s surface penetrate the skin layers to a certain extent, where they can exert their effects. This is the case for topical formulations for treatment of skin disorders such as acne, dermatitis, and psoriasis. However, very few drugs are suitable for delivery by the topical route, as passive penetration through the skin is limited to very small molecules (<500Da), which are neutral and relatively lipophilic. Some considerations of dermatologists would be the vehicle of the topical, specifically if it is in a lotion, cream or ointment form, in increasing order of absorption and effectiveness. This however, is often limited by user preferences, with ointment formulas (more efficacious) deemed cosmetically less acceptable.

The skin is the largest organ of the human body, comprising 15% of body weight and therefore its use to deliver medicine to the body is not a new concept by any means. Advancements made by modern science are improving the skin’s potential as a route for drug administration. Dermatologists are at the forefront of research relating to transdermal drug delivery, given the unique accessibility of the largest organ of the body.

Owing to the drawbacks of topical formulations, transdermal patches have been developed to improve drug delivery through the skin and this is an area that my team has actively researched in the last year as an adjunct to our cosmeceutical formulations.

I have always been interested in finding new methods to allow my patients to achieve optimal results from our cosmeceuticals, thus in this article I shall share some tools which I employ in my clinical practice to achieve optimal absorption of cosmeceutical active ingredients.

Wet Wrap/Occlusion Skin Therapy & Facial Masks

A well known method employed by dermatologists to treat severe eczema known as wet wrap is actually a simple process involving applying a wet textile together with topical medications to skin, to increase absorption of skincare. An example of how and when wet wraps are used— during particularly intense eczema flares with severe itch or pain, wet wrap therapy rehydrates and enhances the absorption of topical medications applied on the skin. The fabric wraps are soaked in water and applied to the affected skin on the body. Wet wraps are best done after bathing, moisturising and applying topicals, then left overnight.

Wet wraps work via 3 different ways:

●  Cooling — as water gradually evaporates from the bandages this cools the skin and helps relieve inflammation, itching and soreness

●  Moisturising — cosmeceuticals covered over with wet bandages are deeply absorbed in to the skin to provide a longer-lasting moisturising effect

●  Absorption — enhanced absorption of any topicals into both the superficial and deeper layers of skin where inflammation is present

Facial sheet masks work in a similar way, on the basis of occlusion. This means that when there’s a topical which is applied on the skin and also in contact with something moist such as a sheet mask, there is increased absorption of the topicals by the skin. In my practice, whenever I want to increase absorption of cosmeceuticals and moisturisers that are dispensed to patients, I would advise them to apply a wet cotton sheet (as a wet wrap) on to their face to increase absorption.

I would consider masking as something which is very good to do if you are already diligent with other aspects of skin health such as cleansing and applying cosmeceuticals. Using a face mask would deliver moisture and clinically active ingredients to the skin—so it is important to look out for ingredients such as glycerin, ceramide and hyaluronic acid, as well as evidence-based antioxidants for anti-ageing such as oligopeptides, vitamin C ( I use sodium ascorbyl phosphate which is a neutral, rather than acidic form of vitamin C, that has minimal skin irritation). Here’s a tip, use a cosmeceutical moisturiser like the Radiance Fluide™ and increase your skin’s absorption by applying it on damp skin, plus a soft wet cotton towel over it.

Facial Massage

Performing a facial massage, such as with the aid of a facial roller before application of cosmeceuticals could increase the skincare absorption, leading to better effects of the anti- aging skincare. Local massage is an established treatment method of improving surgical scars, by stimulating blood flow and improving wound healing. A peer-reviewed study published in a medical journal Complementary Therapies in Medicine led by author Miyaji Akane at the Institute for Liberal Arts, Tokyo Institute of Technology (Tokyo Tech) and colleagues at Tokyo Healthcare University and the Research and Development Center, MTG Co. Ltd. in 2019 had examined the effects of using a facial roller on facial skin and blood flow. The study concluded that there was significantly increased vascular (blood vessel) dilation with use of the facial massage roller. This means that there will be increased absorption of any cosmeceuticals applied on the face following the massage.

My recommendation would be manual rather than electric facial rollers as the latter may cause excessive pressure and irritation (being automated) and is also dependent on user training as well as the manufacturer’s settings, with a potential risk of overheating of electric components. Manual facial massage is a self-regulated process as the user can immediately sense irritation and apply just the right amount of pressure.

Transdermal delivery

Transdermal medications (usually in the form of a patch) are a little more modern and complex. Great strides in transdermal drug delivery have been made since the first transdermal drug was approved by the FDA in 1979.

Transdermal drugs bring medication through the skin, to the bloodstream. Once in the bloodstream, the ingredients circulate and take effect at a targeted location. Medication is delivered steadily and can be stopped simply by removing the patch. Since your body doesn’t have to digest the medicine through the stomach, a higher concentration reaches the bloodstream. The medication permeates the skin in a controlled fashion thus attaining more ready levels of the drug in the body.

The science behind polymers and transdermal drug delivery systems

Polymers are vital in a transdermal drug delivery system. Systems for transdermal delivery are assembled as a multilayered polymeric laminates consisting of a drug reservoir sandwiched in between 2 polymeric layers:

● An outer impervious backing — prevents the loss of drug

● An inner polymeric layer — functions as an adhesive and rate-controlling membrane There are 3 types of transdermal drug delivery systems:

● Reservoir systems

In this system, the drug reservoir is embedded between a backing layer and a rate-controlling membrane.

● Matrix Systems

In this system, the drug reservoir is either dispersed in an adhesive polymer or in a hydrophilic or lipophilic polymer matrix.

● Micro-reservoir Systems

This system is a combination of the above 2 systems. The drug reservoir is formed by suspending the drug in an aqueous solution and then dispersing the solution in a lipophilic polymer to form thousands of microscopic spheres of drug reservoirs.

Polymers used in transdermal delivery systems should have biocompatibility with the drug and other components of the system. They should also provide consistent, effective delivery of a drug throughout the product’s intended shelf life.

An example of a common polymer used are silicones, also known as polysiloxanes, made of many repeating units of siloxanes. Siloxanes are chains of alternating silicon and oxygen atoms that are often combined with carbon and/or hydrogen.
Medical grade silicones are silicones that undergo specific testing for their biocompatibility and have been deemed appropriate to be used for medical applications. Topical silicone therapy is often used by plastic surgeons and dermatologists to treat and heal scars.

Key considerations of a polymer patch used for transdermal drug delivery would be —conformability of the material to be applied to irregular skin or scar surfaces, sensitive regions such as the face/eye area and the overall durability and biocompatibility of medical grade polymers.

The process of skin ageing relates to the ability of the body’s natural healing processes. The same cells which are activated during cell injury are the ones which lose function with ageing, and are responsible for loss of collagen, elastin and the overall loss of volume and elasticity of skin. Specifically, antiageing cosmeceuticals target and stimulate cells known as fibroblasts, which are best thought of as the “soldiers” of wound healing which produce collagen to seal up injured or damaged skin. Injury to the skin occurs over a gradual process in the case of ageing, due to the slowing of one’s biological clock and photodamage.

For the last year, my team and I worked with a material scientist to develop a transdermal delivery patch, the QRASER™ Transdermal absorption patch, launched in July 2019. This patch works via a matrix system of drug delivery. In this system, the drug reservoir is dispersed in an adhesive polymer matrix. The transdermal delivery patch uses a unique polymer technology that mimics the natural hydration and homeostasis of the skin barrier, to enhance cosmeceutical absorption. The focus is on improving absorption via optimisation of the skin healing microenvironment.

The result? Healthy collagen production thus reducing fine lines and wrinkles.

In conclusion, cosmeceuticals in the arena of dermatologist-led skincare research will be increasingly prominent in the next decade of “smart skincare”. This should be emphasised along with understanding of how these topicals work, the limitations of skincare absorption and potential technologies such as transdermal delivery patches which can optimise the anti-ageing benefits of cosmeceutical skincare.

Dr. Teo Wan Lin, founder and medical director of TWL Specialist Skin & Laser Centre, is one of Singapore’s prominent dermatologists specialising in medical and aesthetic dermatology. She is also the founder of Dr.TWL Dermaceuticals which specialised in cosmeceutical skincare. In July 2019, a material science arm Dr.TWL Biomaterials was launched focusing on novel biomaterials for skin and hair application. Click here for the links to our product and here to read more about Dr.TWL Dermaceuticals and here to read more about Dr.TWL Biomaterials.