Common Uses:Off Label Uses:Side Effects:
Some of the common side effects while taking Retin-A Micro include: Acne clinical trial results: In separate clinical trials for each concentration, acne patients treated with Retin-A Micro (tretinoin gel) microsphere 0.1% or 0.04%, analysis over the twelve week period showed that cutaneous irritation scores for erythema, peeling, dryness, burning/stinging, or itching peaked during the initial two weeks of therapy, decreasing thereafter.

Approximately half of the patients treated with Retin-A Micro 0.04% had cutaneous irritation at Week 2. Of those patients who did experience cutaneous side effects, most had signs or symptoms that were mild in severity (severity was ranked on a 4-point ordinal scale: 0=none, 1=mild, 2=moderate, and 3=severe). Less than 10% of patients experienced moderate cutaneous irritation and there was no severe irritation at Week 2.

In studies on Retin-A Micro (tretinoin gel) microsphere, 0.04%, throughout the treatment period the majority of patients experienced some degree of irritation (mild, moderate, or severe) with 1% (2/225) of patients having scores indicative of a severe irritation rating; and 1.3% (3/225) of patients treated with Retin-A Micro (tretinoin gel) microsphere, 0.04%, discontinued treatment due to irritation, which included dryness in one patient and peeling and urticaria in another.

In studies on Retin-A Micro (tretinoin gel) microsphere, 0.1%, no more than 3% of patients had cutaneous irritation scores indicative of a severe irritation rating; although, 6% (14/224) of patients treated with Retin-A Micro (tretinoin gel) microsphere, 0.1% discontinued treatment due to irritation. Of these 14 patients, four had severe irritation after 3 to 5 days of treatment, with blistering in one patient.


Results in studies of subjects without acne: In a half-face comparison trial conducted for up to 14 days in women with sensitive skin, but without acne, Retin-A Micro (tretinoin gel) microsphere, 0.1% was statistically less irritating than tretinoin cream, 0.1%. In addition, a cumulative 21 day irritation evaluation in subjects with normal skin showed that Retin-A Micro (tretinoin gel) microsphere, 0.1%, had a lower irritation profile than tretinoin cream, 0.1%. The clinical significance of these irritation studies for patients with acne is not established. Comparable effectiveness of Retin-A Micro (tretinoin gel) microsphere, 0.1% and tretinoin cream, 0.1%, has not been established. The lower irritancy of Retin-A Micro (tretinoin gel) microsphere, 0.1% in subjects without acne may be attributable to the properties of its vehicle. The contribution to decreased irritancy by the MICROSPONGE System has not been established. No irritation studies have been performed to compare Retin-A Micro (tretinoin gel) microsphere, 0.04%, with either Retin-A Micro (tretinoin gel) microsphere, 0.1%, or tretinoin cream, 0.1%.

Cautions / Warnings:Drug Interactions:
Drug interactions for Retin-A Micro include: Concomitant topical medication, medicated or abrasive soaps and cleansers, products that have a strong drying effect, products with high concentrations of alcohol, astringents, or spices should be used with caution because of possible interaction with tretinoin. Avoid contact with the peel of limes. Particular caution should be exercised with the concomitant use of topical over-the-counter acne preparations containing benzoyl peroxide, sulfur, resorcinol, or salicylic acid with Retin-A Micro (tretinoin gel) microsphere, 0.1% and 0.04%. It also is advisable to allow the effects of such preparations to subside before use of Retin-A Micro (tretinoin gel) microsphere, 0.1% and 0.04%, is begun.