Comedolytic effect

Benzoyl peroxide exercises a potent antimicrobial activity through the release of free oxygen radicals. It suppresses P. acnes in sebaceous follicles much faster than antibiotics, leading to a rapid reduction of the inflammatory lesions number. P. acnes does not develop resistance to benzoyl peroxide, which maintains its efficacy after years of use. Benzoyl peroxide seems to have a mild comedolytic effect while it is not... 

Benzoyl peroxide is easy to use and recommended as first-line therapy in the treatment of mild to moderate noninflammatory acne. Benzoyl peroxide has a comedolytic effect that increases the rate of epithelial cell turnover and helps to unclog blocked pores. It also has antibacterial activity against P. acnes, which appears to be the main reason for the effectiveness of this product.13... 

Benzoyl peroxide is an effective topical agent in the treatment of acnevulgaris. It penetrates the stratum corneum or follicular openings unchanged and is converted metabolically to benzoic acid within the epidermis and dermis. Less than 5% of an applied dose is absorbed from the skin in an 8-hour period. It has been postulated that the mechanism of action of benzoyl peroxide in acne is related to its antimicrobial activity against P acnes and to its peeling and comedolytic effects. 

It has been postulated that the mechanism of action of benzoyl peroxide in acne is related to its antimicrobial activity against P acnes and to its peeling and comedolytic effects. 

White GM. Acne therapy. In James WD, Cockerell CJ, Dzubow LM, et al, eds. Advances in Dermatology. St. Louis, Mosby, 1999 29-59. Fort-Lacoste L, Verscheure Y, Tisne-Versailles J, Navarro R. Comedolytic effect of topical retinaldehyde in tiie rhino mouse model. Dermatology... 

RG. Unna, a German dermatologist, was the first to describe the properties and use of salicylic acid. It has since been used for many decades as a keratolytic agent in concentrations of 3-6%. Salicylic acid is frequently utilized in topical acne preparations because of its comedolytic effects. In addition, it facilitates the penetration of other topical agents. 

Retinoids, which are highly effective in the treatment of acne, stimulate epithelial cell turnover and aid in unclogging blocked pores. Retinoids also exhibit anti-inflammatory properties through the inhibition of neutrophil and monocyte chemotaxis.8 Because of these comedolytic and antiinflammatory effects, topical retinoids are recommended as first-line treatment for mild to moderate comedonal and inflammatory acne.3 While success is seen with monotherapy, using a retinoid in combination with benzoyl peroxide or topical antibacterials is also an appropriate and effective therapeutic treatment option.3 Tretinoin, adapalene, and tazarotene are topical retinoids available for use in the treatment of acne. Table 62-2 describes the strengths and formulations of these agents. 

Keratolytics may be less irritating than benzoyl peroxide and tretinoin, but they are not as effective comedolytic agents. 

Patients should understand that effectiveness of any therapeutic regimen may require 6 to 8 weeks and that they may also notice an exacerbation of acne after initiation of topical comedolytic therapy. 

It is thought to be both comedolytic, mainly through an irritant effect leading to increased turnover of the follicular epithelial cells and increased sloughing, and bactericidal against P. acnes. Benzoyl peroxide is lipophilic and penetrates the follicle well once absorbed it releases oxygen, which suppresses the bacteria, and reduces the production of irritant free fatty acids. 

Tazarotene is used in the treatment of mild to moderate acne vulgaris and has comedolytic, keratolytic, and anti-inflammatory action. Tazarotene 0.1% and 0.05% gel and cream have been shown to be more effective than vehicle in the treatment of acne vulgaris." " The 0.1% gel was slightly more effective than the 0.05% gel in decreasing lesion counts, with treatment snccess rates of 68% and 51% of patients, respectively. ... 

Retinaldehyde is biotransformed into all-frani -retinoic acid and induces biologic effects including comedolytic activity similar to those of topical tretinoin when administered at comparatively lower concentrations. ... 

Salicylic acid has comedolytic and anti-inflammatory action. Also known as /3-hydroxy acid, it is deemed a more effective comedolytic than most a-hydroxy acids. In addition, it increases penetration of other substances, and in low concentrations is bacteriostatic and fungistatic. ... 

Although evidence for efficacy in the treatment of acne is conflicting, each agent has been classified as safe and effective by an advisory review panel of the FDA. Some combinations of these agents may be considered synergistic (e.g., sulfur and resorcinol, salicylic acid, BPO). Keratolytic products, in the concentration allowed, may be less irritating than BPO and tretinoin however, they are not considered as effective comedolytic agents, as are BPO and tretinoin. 

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