BLAINE, WASH. — Topical calcineurin inhibitors remain an excellent second-line treatment for atopic dermatitis in children, despite a public health advisory by the Food and Drug Administration earlier this year and the promise of a black-box warning in the near future, Robert Sidbury, M.D., said at a conference sponsored by the North Pacific Pediatric Society.
Dr. Sidbury, of the University of Washington, Seattle, addressed the questions of when and how to use the topical calcineurin inhibitor (TCI) tacrolimus (Protopic) and pimecrolimus (Elidel) for atopic dermatitis in light of the FDA warning.
TCIs should be used only for short-term or intermittent long-term treatment, he said. They should not be used continually, on large body-surface areas, or on children younger than 2 years of age except in unusual circumstances.
“If I felt that an infant was using so much topical steroid that I was worried, I would use [a TCI] in a heartbeat, and with the cleanest conscience that I know how to have,” Dr. Sidbury said.
TCIs seem to work best on skin folds and on the head and neck. These happen to be the areas where the use of topical steroids is most problematic, since thinning of the skin is a well-known side effect of these agents. Additionally, topical steroids carry the risk of glaucoma and cataracts when used near the eyes.
TCIs are least effective on palms and soles; on thick, lichenified areas; and on hyperkeratotic areas such as those seen in psoriasis.
These agents tend to sting quite a bit when used on open, excoriated areas, and Dr. Sidbury suggested pretreating those areas with topical steroids before introducing a TCI.
TCIs should be applied twice daily to affected areas to induce remission and then as needed for flares. To avoid continual use, they can be alternated with topical steroids, thus decreasing the potential for side effects from both agents. And TCIs should be part of a total skin-care regimen, including bathing, moisturizing, avoiding irritants and allergens, and using antibiotics and antihistamines when appropriate.
There are some differences between tacrolimus and pimecrolimus. Tacrolimus is said to be better for moderate to severe atopic dermatitis, whereas pimecrolimus is said to be better for mild to moderate disease.
Tacrolimus comes in two strengths, 0.03% and 0.1% in an ointment base. The lower dose is approved for children aged 2–15 years, and the higher dose is approved for adults and children older than 15 years. Pimecrolimus comes in a single, 1% cream formulation that's approved for use in children older than 2 years.
A review of three randomized head-to-head studies indicated that tacrolimus is more effective on thicker, more refractory areas and has a faster onset of action. Pimecrolimus, on the other hand, stings less (J. Am. Acad. Dermatol. 2005;52:810–22).