New Topical Retinoids Simplify Acne Treatment

/Home/Acne Therapy: Treatments & Cure/Topical Retinoids

New Topical Retinoids Simplify Acne Treatment
Family Pratice News , Oct 1, 2000 by Timothy F. Kirn

MONTEREY, CALIF. -- The new retinoids are much less irritating than traditional topical traditional and thus have made acne treatment with topical retinoids not only more tolerable but much simpler, Dr. Renee M. Howard said at a symposium sponsored by the American Academy of Pediatrics California Chapter 1.

Topical tretinoin creams and gels are now formulated with vehicles that keep the medication on the skin and release it more evenly reducing transdermal penetration and thereby causing less irritation.

These new vehicles make it much easier to start therapy with topical retinoids, said Dr. Howard, a pediatric dermatologist at Children's Hospital Oakland (Calif.).

In the past, tretinoin (Retin-A) therapy was begun using the 0.025% cream once a week and then slowly working up to the 0.1% gel or the strongest preparation the patient could tolerate. With the new retinoid preparations, there is less need to start so slowly.

This broader range of treatment options has made choosing the best agent for a patient more complicated, Dr. Howard said.

Dr. Howard did not spell out specific guidelines for treating acne but made these comments about various agents:

Retinoids

Tretinoin is now available generically making it much less expensive. However, the newer preparations, which are not generic, are much less irritating.

* Retin-A Micro Gel (tretinoin). The tretinoin in Retin-A Micro gel is encapsulated in microspheres to slow its release and reduce irritation. Dr. Howard recommends having patients begin by using the 0.1% gel twice a week at first, and then working their way up to using it every day, as tolerated.

* Avita Cream (tretinoin). The tretinoin in Avita (0.025%) is attached to high-molecular-weight oligomers that keep it from penetrating transdermally and causing irritation. Although it is somewhat irritating and should be started with twice-weekly use, it is the least irritating of all the retinoids.

* Differin (adapalene 0.1% gel). Adapalene is a synthetic retinoid that is lipophilic, so it concentrates in the pilosebaceous follicles and oily areas. Adapalene also binds more selectively than tretinoin. The-oretically, these properties make adapalene much less irritating. "But I can tell you irritation can still be an issue," Dr. Howard said. Of the retinoid agents, he recommended adapalene for younger patients specifically because there are fewer stringent recommendations for its use.

Other Agents

* Benzoyl Peroxide. Topical benzoyl peroxide is inexpensive and effective, so it is often the first choice for the patient who has superficial acne. The recommendation has been to use the 5% or 10% concentration of topical benzoyl peroxide, but Dr. Howard finds the 10% strength too irritating for most patients. In her experience, it is no more effective than the 2.5% or 5% concentration.

* Tetracycline. Because tetracycline must be taken on an empty stomach, its usefulness is limited. Dr. Howard tends not to recommend tetracycline for boys because she thinks they have more difficulty adhering to the empty-stomach direction.

* Doxycycline. This antibiotic can be considered as an alternative to oral tetracycline. It doesn't need to be taken on an empty stomach, but it is highly photosensitizing. For this reason, avoid initiating doxycycline during the summer months.

* Erythromycin. Topical erythromycin comes in an ointment formulation, which is good for patients who have atopic tendencies. Orally it is the least effective of the antibiotics used for acne, but it is also the only one that is not teratogenic, so it is often the drug to use in adolescent girls. Propionibacterium acnes does become resistant to erythromycin, so it is generally not a good choice for long-term treatment.

* Minocyline. Oral minocycline is more expensive than the other antibiotics, but its advantages are that it does not cause stomach upset or yeast infections. Of the antibiotics, it may be the most effective. Dr. Howard uses minocycline for inflammatory acne or in those patients who cannot take doxycycline. Rarely patients will have a severe reaction to minocycline that includes fever, rash, and hepatitis occurring in the first 2 months of use.

* Benzoyl Peroxide and Erythromycin (benzamycin gel). The combination of these two agents works better than either one alone. The disadvantage is that it needs to be refrigerated. This is best for use in a young child with significant inflammatory acne when the physician does not want to use systemic treatment.

* Azelaic Acid. It is not as effective as benzoyl peroxide and it costs more. The advantage of azelaic acid is that it bleaches out hyperpigmentation and thus can be used for patients whose acne has left post-inflammatory hyperpigmented areas.

* Clindamycin. Topical clindamycin is available in a lotion, which allows for easy application. Dr. Howard uses clindamycin for those patients who are allergic to topical benzoyl peroxide.
COPYRIGHT 2000 International Medical News Group