Ask the Ecz-perts: CASM and the Aron Regimen

Ask the Ecz-perts

By National Eczema Association

Published On: Oct 26, 2020

Last Updated On: Mar 15, 2021

Ask the Ecz-perts gives leading medical experts an opportunity to answer your most pressing questions about eczema and its related health conditions.

In this edition of Ask the Ecz-perts, Richard Aron, MB Ch B, who is founder of the Aron Regimen and a private practice consultant dermatologist registered with the Human Sciences Council of South Africa, answers questions about the Aron Regimen.

In the Aron Regimen, what does CASM stand for?

Compounded antibacterial, steroid and moisturizer (CASM) is a combination of antibiotic cream or ointment steroid cream or ointment and moisturizing products. The objective is to only treat the inflammation characteristic of eczema, but also the infection, which is invariably present in chronic and severe cases. We want to be able to apply both the steroid and topical antibiotic products to wide areas of the skin, as appropriate and in a safe manner.

Aren’t there safety concerns around long-term use of topical corticosteroids?

There are indeed concerns about the potency of using topical corticosteroids and the potential for resistance in using topical antibiotics. And these are real questions, but they may be significantly allayed by delivering low-potency steroid and antibiotic via the moisturizing component of the compound. This slow potency situation enables the therapy to be maintained for longer periods, even when the skin is much improved.

Treating until controlled and then stopping the treatment completely until the next flare is not, in my opinion, an appropriate approach for a chronic condition such as atopic dermatitis.

Corticosteroids, including topical corticosteroids (TCS), are associated with a potentially serious condition called Topical Steroid Withdrawal (TSW). TSW is thought to be rare but can be debilitating for some patients. It may not be recognized by all health professionals as clear diagnostic criteria do not yet exist. Learn more about TSW and appropriate use of TCS.

Most people don’t realize your regimen is more than just a mixture of ingredients. I understand that proper guidance with tapering of the compound is also key to the success of the treatment. What is your methodology for tapering on CASM?

You are 100% correct, tapering of the CASM compound is of the essence. The reason for this is that, as the skin improves and the symptoms abate, the frequency of application of the compound should be reduced slowly but steadily over a period of time. This reduction in frequency of application reduces the dose of steroid delivered to the skin and therefore reduces the potential for steroid side effects such as absorption of the steroid or skin thinning.

The pace of reduction depends on the clinical response of the patient. The more rapid the initial response, the more rapid one may reduce the frequency of application. This is a clinical decision to be made by the physician in charge of the patient who should be reporting their progress to their physician at regular intervals.

As a rule of thumb — just to give you a general idea— at the beginning of therapy, I usually request applications be maintained for 10 days. With progress, the first reduction may be maintained for two weeks. The next reduction could probably be maintained for three to four weeks, and so forth. The ultimate objective of this tapering protocol is to maintain the improved condition on a low-level application frequency.

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Photo courtesy of Tori Soper Photography

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