Renova Retin-A
Tretinoin treatment before carbon-dioxide laser resurfacing: a clinical and biochemical analysis.

Orringer JS, Kang S, Johnson TM, Karimipour DJ, Hamilton T, Hammerberg C, Voorhees JJ, Fisher GJ.

Department of Dermatology, University of Michigan Medical School, Ann Arbor, Michigan 48109-0314, USA. jorringe umich.edu

BACKGROUND: Tretinoin is often prescribed before laser resurfacing in an attempt to enhance results. OBJECTIVE: We sought to assess the clinical and biochemical effects of preoperative tretinoin use before laser resurfacing. METHODS: Patients were randomized to apply tretinoin to one forearm and placebo to the other for 3 weeks. Patients' photodamaged forearms were focally treated by carbon-dioxide laser resurfacing. Biopsy specimens were obtained at baseline and various times posttreatment. Real-time polymerase chain reaction technology was used to quantify messenger RNA levels of types I and III procollagen and matrix metalloproteinases-1, 3, and 9. Wounds were assessed for degree of re-epithelialization using a computer graphics-generated template. A colorimeter was used to quantify postoperative erythema. RESULTS: No substantial differences in either biochemical markers or clinical end points were identified between tretinoin and placebo pretreated forearms. CONCLUSIONS: We found no evidence of enhanced collagen formation, accelerated re-epithelialization, or quicker resolution of postoperative erythema with tretinoin pretreatment before laser resurfacing.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15583586&dopt=Abstract tretinoin Retin-A Renova



Renova Retin-A
Interventions for photodamaged skin.

Samuel M, Brooke R, Hollis S, Griffiths C.

Clinical Trials & Epidemiology Research Unit, Ministry Of Health, 226 Outram road, Block A #02-02, Singapore, South East Asia, SINGAPORE.

BACKGROUND: Photodamage describes skin changes such as fine and coarse wrinkles, roughness, freckles and pigmentation changes that occur as a result of prolonged exposure to the sun. Many treatments are available to reverse the damage, but it is unclear which work and at what cost in terms of unwanted side effects. OBJECTIVES: To assess the effects of topically applied treatments, tablet treatments, laser and surgical procedures for photodamaged skin. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, Issue 1 2002, MEDLINE (1966-June 2002), EMBASE (1974-June 2002), Health Periodicals (1976-June 2002). We checked references of articles and communicated with authors and the pharmaceutical industry. SELECTION CRITERIA: Randomised controlled trials which compared drug or surgical interventions with no treatment, placebo or another drug, in adults with mild, moderate or severe photodamage of the face or forearms. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed trial quality. MAIN RESULTS: Thirty studies of variable quality were included.Eight trials showed that topical tretinoin cream, in concentrations of 0.02% or higher, was superior to placebo for participants with mild to severe photodamage on the face and forearms (although losses to follow-up were relatively high in most studies). For example, the relative risk of improvement for 0.05% tretinoin cream, compared to placebo (three studies), at 24 weeks, was 1.73 (95% confidence interval 1.39 to 2.14). This effect was not seen for 0.001% topical tretinoin (one study) or 0.01% (three studies). A dose-response relationship was evident for both effectiveness and skin irritation.One small within-patient study showed benefit from topical abscorbic acid compared with placebo.Tazarotene (0.01% to 0.1%) and isotretinoin (0.1%) both showed significant improvement over placebo for moderate photodamage (one study each).There is limited evidence (one trial), to show that the effectiveness of 0.05% tretinoin, is equivalent to the effects of 0.05% and 0.1% tazarotene.One small study showed greater improvement in upper lip wrinkles with CO2 laser technique compared to Baker's phenol chemical peel, at 6 months.Three small RCTs comparing CO2 laser with dermabrasion found no difference in wrinkle score at 4 to 6 months, suggesting that both methods are equally efficacious, but more erythema was reported with the laser.The effectiveness of other interventions such as hydroxy acids and natural polysaccharides was not clear. AUTHORS' CONCLUSIONS: There is conclusive evidence that topical tretinoin improves the appearance of mild to moderate photodamage on the face and forearms, in the short term. However erythema, scaling/dryness, burning/stinging and irritation may be experienced initially.There is limited evidence that tazarotene and isotretinoin benefit patients with moderate photodamage on the face: both are associated with skin irritation and erythema. The effectiveness of other interventions remains uncertain.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15674885&dopt=Abstract tretinoin Retin-A Renova



Renova Retin-A
Retinoid therapy for acne. A comparative review.

Chivot M.

Hopital Saint-Louis, Paris, France. martine.chivot wanadoo.fr

Retinoids play a vital role in the treatment of acne because they act on the primary lesion, the microcomedo. They are synthetic derivatives of vitamin A (retinol), and are selected for their effectiveness. Several compounds are used for acne, either in topical or systemic form.We describe and compare the different topical retinoids, tretinoin (all-trans-retinoic acid), isotretinoin (13-cis-retinoic acid), adapalene (derived from naphthoic acid), and tazarotene (acetylenic retinoid). They act mainly as comedolytics, but anti-inflammatory actions have also been discovered recently. The retinoids have great beneficial effects, but also some adverse effects, the main one being teratogenicity. It is preferable not to use them in topical form for pregnant women, although a pregnancy test is only compulsory for tazarotene.Only isotretinoin is used in systemic form. It acts on all the factors of acne and offers long remissions, and sometimes complete cures. Precautions must be taken for women of childbearing age due to its teratogenicity. It is also important to be aware of its other adverse effects, explain them to the patient and, if possible, deal with them in advance.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15675886&dopt=Abstract tretinoin Retin-A Renova



Renova Retin-A
Mechanisms of the comedolytic and anti-inflammatory properties of topical retinoids.

Bikowski JB.

Bikowski Skin Care Center, Sewickley Station, Sewickley, PA 15143-1051, USA.

Retinoids comprise a family of compounds with structures and mechanisms of action that resemble those of vitamin A (retinol), an essential nutrient which plays a role in cell growth and differentiation. The retinoids, which interact with nuclear receptors and affect gene transcription, have enormous therapeutic potential, particularly if they are receptor- and function-selective. Tretinoin was the first topical retinoid employed for the treatment of acne. In recent years, other topical retinoids for the treatment of acne have been designed from a disease-specific approach, with enhanced receptor and function selectivity, which translates to improved therapeutic effects and more favorable tolerability. The properties that differentiate the topical retinoids tretinoin, adapalene, and tazarotene have permitted clinicians to tailor acne treatment regimens for maximum therapeutic outcomes. Tretinoin (all-trans-retinoic acid), considered a first-generation retinoid, acts by altering the milieu of the microcomedo and influences desquamation of abnormal epithelium. Two receptor-selective synthetic retinoids, adapalene and tazarotene, may be classified as third-generation retinoids. Adapalene, a derivative of naphthoic acid, has comedolytic, antiproliferative, and anti-inflammatory properties. Tazarotene is a prodrug metabolized to tazarotenic acid that modulates cellular differentiation, desquamation, and inflammation.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15696984&dopt=Abstract tretinoin Retin-A Renova