BLAINE, WASH. — Topical retinoids can be highly effective treatments for acne; however, they come in a bewilderingly wide variety of strengths and formulations.
Clinicians should consider effectiveness, tolerability, and the type of vehicle that would be best for an individual patient in making the choice, Robert Sidbury, M.D., said at a conference sponsored by the North Pacific Pediatric Society.
Physicians must choose among adapalene (Differin) 0.1%, which comes formulated as a gel, a cream, a solution, and as pledgets; tretinoin (Retin-A), which comes in four strengths between 0.01% and 0.1% as a cream and 0.01% and 0.025% as a gel; tretinoin micro (Retin-A Micro) gel, which comes in 0.04% and 0.1% strengths; and tazarotene (Tazorac), which comes as a gel and as a cream in 0.05% and 0.1% strengths.
Adapalene is at the top of the tolerability list, said Dr. Sidbury of the University of Washington in Seattle. Tretinoin micro comes next, followed by tretinoin. Tazarotene is the least tolerable of the retinoids.
Unfortunately, the least tolerable topical retinoid is the most effective, and the most tolerable is the least effective. Those patients who are able to tolerate tazarotene are likely to find that it works better for them than do the alternatives.
Retinoids that are formulated in creams tend to be better tolerated—but less effective in equal strengths—than those formulated in gels, Dr. Sidbury said.
There are things patients can do and things physicians can do to optimize success with topical retinoids, he said. Although all these products are intended to be used daily, patients who are particularly sensitive can apply them every other day or even just twice a week to start.
Retinoids thin the stratum corneum, and this presents as dryness, itchiness, and desquamation. However, the stratum corneum regenerates even as the patient continues to use the retinoids, so tolerability should improve with continued use.
Patients should apply topical retinoids very sparingly. A pea-sized dollop on a fingertip is enough to cover the entire acne-prone “T zone” of the face, said Dr. Sidbury.
And the physician should counsel patience, because it can take quite a long time for the patient to see improvement.
Physicians can help by matching the vehicle to the patient's skin type. Patients with oily skin will do better with a gel, whereas patients with dry skin will do better with a cream. One should start with products at the top of the tolerability scale for patients with sensitive skin, but go with something stronger in patients whose skin is not quite as sensitive, Dr. Sidbury advised.