It is important to use the correct amount of topical steroid for your eczema, as instructed by your healthcare professional. Topical steroids should be applied with clean hands so that the skin just glistens. It can sometimes be difficult to judge how much steroid to use and there are guidelines on the amount required to cover body areas that are affected by eczema. These are based on the Finger Tip Unit (FTU), and explained in detail in our fact sheet which you can download as a pdf from the related documents to the right of this page.
The most common side effect of topical corticosteroid use is skin atrophy. All topical steroids can induce atrophy, but higher potency steroids, occlusion, thinner skin, and older patient age increase the risk. The face, the backs of the hands, and intertriginous areas are particularly susceptible. Resolution often occurs after discontinuing use of these agents, but it may take months. Concurrent use of topical tretinoin (Retin-A) % may reduce the incidence of atrophy from chronic steroid applications. 30 Other side effects from topical steroids include permanent dermal atrophy, telangiectasia, and striae.
Why are different strengths critical? The appropriate strength depends on many factors. For example, babies absorb topical steroids faster than adults, so they may require a low-potency steroid. Areas of the body where skin touches skin (think: armpits, rectal area, etc), as well as sensitive areas (like the skin on the eyelids), tend to absorb topical steroids more rapidly, so those regions of the body also usually require a low-potency steroid. However, thick, rough skin on the palms of the hands and the soles of the feet usually absorb topical steroids more slowly than other parts of the body, so those areas typically require a more potent steroid. Keep in mind: The greater the potency of the steroid (in other words, the lower its class number), the more likely it is to cause side effects .