In an earlier post I was discussing dry skin and how common it is on the foot, particularly as we get older. In this post, I would just like to highlight a few things which may be helpful when discussing emollients and emollient choices with your patients.
With most things in healthcare giving the right advice is all about accessing good evidence in the first place. Despite dry skin being a common dermatological symptom, the evidence base guiding its management is limited. Most of the work which covers this topic is more clinically derived from experience and observation than hardcore research.
Their basic mode of action is to increase the amount of water within the epidermis. They can do this by:
1. Occlusion, for example a grease/oil based vehicle can occlude the epidermis and reduce water loss from it.
2. Or, by including active ingredients which are able to draw in water from the dermis, known as a humectants. Urea which is widely used in foot based emollients is a good example of a humectant.
The skin can be thought of as a brick wall composed of brick ("corneocytes" ) and mortar (natural moisturising factors in the skin). The skin gets dry due to many reasons, but typically the natural moisturising factors are stripped out by washing and use of products which contain sodium laureth sulfate (SLS) and other additives which act as detergents. This is the equivalent of removing the mortar from between the brick meaning cracks appear and so not only is more water lost from the skin but also external agents can make their way into the skin much more easily (infections, allergens, irritants and chemicals).
Restoring the skins natural barrier by increasing the water and waterproofing in the skin can not only make the skin feel better but also reduce itching, redness and inflammation and this is achieved through the application of moisturisers or emollients. There are an array of different types of emollients that can be bought but generally they come under the following groups:
1. Cleansing products which are formulated as bath additives and wash products (soap substitutes)
2. Leave on products such as creams, ointments, gels, mousses and sprays etc.,
Top Tips for Emollients on the foot
1. The best emollient is the one that the patient likes and therefore will use! So its best not to dictate a specific name or brand but rather suggest patients speak to their pharmacist, or even better, keep a range of samples in the clinic and give the patient a few to try to see what they like best. Most emollient manufacturers and Pharma companies are more than happy to supply patient samples if you get in touch. Having these in clinic, the patient can take them away to try.
2. For general emollients, they are best applied just after a bath or shower when the skin is warm and slightly damp but do warn you patients some preparations can be slippery - so do take care!
3. When the patient has a very dry skin, the use of a soap substitute in the bath or shower can really improve the amount of moisturization. Most products available in pharmacies have a leave on product and frequently offer matching wash products too.
4. How much should you use? Well, as often as you can but an average pair of feet can probably use 4g of emollients per day. If you are wondering how much that is, help is at hand. Most emollients come in a pump dispenser, which is handy because one full "press" on the pump equals roughly one gram. So this can be a useful guide for patients.
5. Pump dispensers generally are a good idea as they are less likely to suffer contamination than tubes or tubs of products for example. There is some research out there which has shown this.
6. Urea based products are ideal for feet as they are humectant and have a range of biochemical properties which benefit the thicker skin on the soles (and palms). Generally the higher the percentage the better - ideally around 20-25%. Beware though as any higher and urea at 30% has been shown to possess keratolytic properties and should be used under close supervision and certainly should be used with caution in those with diabetes and PVD, for example.
7. There are plenty of urea based products on the market for feet. Brand leaders generally are more expensive to purchase over the counter, so do check to see if your local pharmacy has an own brand, or lesser known ones which will save the patient money - if they cannot get them on prescription.
For more information, please download an article I wrote entitled "Emollients and the foot" which is also available from the publications page. I would also recommend reading "Best Practice in Emollient Therapy" - available for download as a PDF by clicking this link