Retinoic acid topical

Among retinoids, 13-cis-retinoic acid is known to have not only anti-inflammatory but also sebostatic effects. Therefore it is one of the most potent topical and also systemic agents for therapy of acne. 

Drug treatment of photoaged skin can be categorized as antioxidants, a-hydroxy acids and topical retinoids. Of these three approaches only topical retinoids, particularly retinaldehyde and alWrans-retinoic acid, have a well documented ability to restorethe repair... 

Actinic keratoses were the first skin lesions to be treated topically with all-frans-retinoic acid. In various clinical trials, retinoids have been shown to be active in chemoprevention and treatment or prevention skin malignancies [2]. 

Kimbrough-Green CK, Griffiths CE, Finkel LJ, et al (1994) Topical retinoic acid (Tretinoin) for melasma in black patients-a vehicle controlled clinical trial. Arch Dermatol 130 727-733... 

Griffiths CE, Finkel LJ, Ditre CM, et al (1993) Topical tretinoin (retinoic acid) improves melasma a vehicle-controlled, clinical trial. Br J Dermatol 129 415-421... 

Kang et al. [23] compared the clinical, histologic, and molecular responses of normal human skin to topical retinol with that of retinoic acid. Application of retinol and retinoic acid produced epidermal thickening. However, retinol produced less erythema compared with retinoic acid. The authors suggest that these data are compatible with the idea that retinol may he a pro-hormone of retinoic acid. 

Griffiths CE, Kang S, Ellis CN, Kim KJ, Finkel LJ, Ortiz-Ferrer LC, White GM, Hamilton TA,Voorhees JJ (1995) IVvo concentrations of topical tretinoin (retinoic acid) cause similar improvement of photoaging but different degrees of irritation. A double-blind, vehicle-controlled comparison of 0.1% and 0.025% tretinoin creams. Arch Dermatol 131 1037-1044... 

Griffiths CEM, Goldfarb MT, Finkel LJ, et al (1994) Topical tretinoin (retinoic acid) treatment of hyperpigmented lesions associated with photoaging in Chinese and Japanese patients a vehicle-con-trolled trial. J Am Acad Dermatol 30 76-84... 

Bulengo-Ransby SM, Griffiths C, Kimbrough-Green CK, Finkel LJ, Hamilton TA, Ellis CN, Voorhees JJ (1993) Topical tretinion (retinoic acid) therapy for hyperpigmented lesions caused by inflammation of the skin in black patients. New Engl J of Med 328 1438-1443... 

Topical retinoic acid has been shown to have a beneficial effect on the vascular component of rosacea (0.025-0.05% cream once a day) [7]... 

Aryl esters of retinoids have also received some interest. The 4-(acet-amido)phenyl ester of (all- )-retinoic acid, for example, showed topical activity in various animal models but was ineffective for the local treatment of acne in patients [86]. This difference is probably due to the prodrug being readily hydrolyzed in mice skin homogenates but not in human skin preparations. 

Thalidomide (Thalomid) Topotecan (Hycamtin) Tretinoin, Topical [Retinoic Acid] (Retin-A, Avita, Renova, Retin-A Micro)... 

There are many retinol containing preparations to treat vitamin deficiency states. Retinoids are also used to treat dermatological diseases like acne, psoriasis, Darier s disease, and ichthyosis. Tretinoin, all-trans-retinoic acid, is a topical preparation while isotretinoin or 13-cis-retinoic acid, and etretinate are available for oral administration. 

Tretinoin or retinoic acid is the acid form of vitamin A. Actually it is the all-trans isomer of retinoic acid. It is an effective topical agent for acne vulgaris. Its mechanism of action is believed to be associated with increased epidermal cell turnover. Some 10% of the topically applied dose is absorbed, metabolized by the liver and excreted in the urine and bile. To be effective tretinoin should be applied in a concentration that results in mild irritation and erythema. Patients should be advised to avoid or minimize sun exposure and use a protective sun screen as animal studies have raised some concern about possible carcinogenic effects under the influence of ultraviolet radiation. There are no indications that topical tretinoin is associated with an increased risk for birth defects. 

Attractive alternative to oral retinoid therapy in psoriasis (e.g., etretinate), primarily due to less toxicity. Structural changes to the basic retinoid structure (e.g., conformational rigidity) are claimed to enhance therapeutic efficacy and reduce the local toxicity associated with topical tretinoin (retinoic acid). However, place in therapy should await direct comparisons vs standard regimens in terms of efficacy, toxicity, and cost... 

Retinoic acid is an effective treatment of acne vulgaris and is used topically. It stabilizes lysosomes, increases ribonucleic acid polymerase activity, increases prostaglandin E, cAMP and cGMP level. 

Retinoic acid is insoluble in water but soluble in many organic solvents. Topically applied retinoic acid remains chiefly in the epidermis, with less than 10% absorption into the circulation. The small quantities of retinoic acid absorbed following topical application are metabolized by the liver and excreted in bile and urine. 

Topical retinoic acid is applied initially in a concentration sufficient to induce slight erythema with mild peeling. The concentration or frequency of application may be decreased if too much irritation occurs. Topical retinoic acid should be applied to dry skin only, and care should be taken to avoid contact with the corners of the nose, eyes, mouth, and mucous membranes. During the first 4-6 weeks of therapy, comedones not previously evident may appear and give the impression that the acne has been aggravated by the retinoic acid. However, with continued therapy, the lesions will clear, and in 8-12 weeks optimal clinical improvement should occur. A timed-release formulation of tretinoin containing microspheres (Retin-A Micro) delivers the medication over time and may be less irritating for sensitive patients. 

The most common adverse effects of topical retinoic acid are erythema and dryness that occur in the first few weeks of use, but these can be expected to resolve with continued therapy. Animal studies suggest that this drug may increase the tumorigenic potential of ultraviolet radiation. In light of this, patients using retinoic acid should be advised to avoid or minimize sun exposure and use a protective sunscreen. Allergic contact dermatitis to topical retinoic acid is rare. 

Tazarotene (Tazorac) is a topical acetylenic retinoid prodrug that is hydrolyzed to its active form by an esterase. The active metabolite, tazarotenic acid, binds to retinoic acid receptors, resulting in modified gene expression. The precise... 

Alitretinoin (Panretin) is a topical formulation of 9-c/s-retinoic acid which is approved for the treatment of cutaneous lesions in patients with AIDS-related Kaposi s sarcoma. Localized reactions may include intense erythema, edema, and vesiculation necessitating discontinuation of therapy. Patients who are applying alitretinoin should not concurrently use... 

Systemically administered retinoids such as isotretinoin (1, Accutane ) have several disadvantages such as a relatively narrow therapeutic index and a variety of toxic effects including teratogenicity. Topically administered retinoids may avoid some of those drawbacks. For instance, tazarotene (2, Tazorac ) is a topical receptor-selective retenoid that normalizes differentiation and proliferation of keratinocytes. Its major metabolite, tazarotenic acid (11), binds to retinoic acid receptors (RARs) with high affinity. 

Acne and psoriasis Dermatologic problems such as acne and psoriasis are effectively treated with retinoic acid or its derivatives (see Figure 28.21). Mild cases of acne, Darier disease, and skri aging are treated with topical application of tretinoin (all trans retinoic acid), as well as benzoyl peroxide and antibiotics. [Note Tretinoin is too toxic for systemic administration and is confined to topical application.] In patients with severe recalcitrant cystic acre... 

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