Keratolytical agents

Medicated Dandruff Shampoos. Dandmff is a scalp condition characterized by the production of excessive cellular material (18). A number of shampoos have been marketed which are designed to control and alleviate this condition, and many additives have been included in shampoo compositions to classify them as treatment products for dandmff. These additives include antimicrobial additives, eg, quaternary ammonium salts keratolytic agents, eg, saUcychc acid and sulfur heavy metals, eg, cadmium sulfide coal tar resorcinol and many others. More recent (ca 1993) systems use selenium sulfide [7488-56-4] or zinc pyrithione [13463-41 -7] as active antidandmff shampoo additives. Both of these additives are classified as dmgs, but can be found in over-the-counter products. A stronger version, incorporating the use of higher levels of selenium sulfide in a shampoo, is available but requires a prescription for purchase. 

Sahcyhc acid USP, EP, and other pharmacopeia grades are used medically as antiseptic, disinfectant, antifungal, and keratolytic agents. Sahcyhc acid is formulated in lotion or ointment formulations for the treatment of dandmff, eczema, psoriasis, and various parasitic skin diseases. Because the keratolytic property of this aromatic acid has use in the safe removal of dead skin cells from the surface of healthy skin, the acid is used in concentrated sahcyhc acid solutions or suspensions to remove warts and corns. In more dilute form, sahcyhc acid preparations have found use in dandmff and eczema treatment. Sahcyhc acid has been considered and found effective by the Advisory Committees to the FDA in various over-the-counter (OTC) dmg regulated uses. Among these are acne products, dermatitis, dry skin, dandmff and psoriasis products, and foot care products (24). 

Other drugs are a combination of a keratolytic agent (mesulfen [135-58-0] C24H22S2) and the well-known antimycotic 2inc undecylenate [557-08-4] ... 

A keratolytic agent would be safe to use on which of the following skin conditions ... 

P.G. 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 to 6%. Salicylic acid is frequently utilized in topical acne preparations because of its comed-olytic effects. In addition, it facilitates the penetration of other topical agents. 

Keratolytic agents such as salicylic acid are often added to bath oil or shampoos (typically 3% to 4%) for scalp psoriasis.10 Salicylic acid can also be added to topical corticosteroid preparations to enhance steroid penetration (salicylic acid breaks down keratin). 

The description given is typical of verrucas. Verrucas are plantar warts caused by the human papilloma virus affecting the sole of the foot in pressure areas. The lesion is pushed into the epidermis eventually forming a dry hard plaque with a small central black core, which comprises blood vessels. Preparations containing salicylic acid, which is a keratolytic agent, may be used as treatment. Diabetic patients should be referred. 

Verrucas are caused by the human papilloma virus. Verrucas are warts having a characteristic cauliflower-like appearance. Verrucas are contracted from swimming pools and public baths. They are painful when pressure is applied. Treatment involves removal of the hyperkeratolytic skin layers by the use of keratolytic agents such as salicylic acid. 

Athlete s foot, tinea pedis, is a condition caused by a fungus. Management of athlete s foot lies with the use of antifungal preparations such as clotrimazole (an imidazole antifungal) and tolnaftate. Salicylic acid is a keratolytic agent indicated for use in treatment of corns, calluses and warts. 

Topical products for removal of corns and calluses often contain salicylic acid at a concentration of between 11% and 50% as a keratolytic agent in combination with lactic acid, the latter intended to aid absorption. 

Benzoyl peroxide promotes the shedding of keratinised epithelial cells on the skin and is therefore a keratolytic agent. In the treatment of acne it is indicated as a first-line agent in the form of topical preparations. Benzoyl peroxide is mildly irritant, particularly during the early stages of treatment and hence a low strength is chosen to initiate treatment. Moreover aqueous preparations are preferred over alcoholic preparations, to avoid irritation. 

Salicylic acid is a keratolytic agent that removes layers of cornified skin cells. Treatment for corns, calluses and warts involves the application of salicylic acid at a concentration of 1 1-50%. Salicylic acid is contraindicated in allergic patients and its use should be avoided in diabetic patients. 

Photosensitivity It is advisable to rest a patient s skin until effects of keratolytic agents subside before beginning tretinoin. Minimize exposure to sunlight and sunlamps, and advise patients with sunburn not to use tretinoin until fully recovered because of heightened susceptibility to sunlight as a result of tretinoin use. Patients who undergo considerable sun exposure due to occupation and those with inherent sun sensitivity should exercise particular caution. Use sunscreen products and wear protective clothing over treated areas. Weather extremes, such as wind and cold, also may irritate treated areas. 

Propylene glycol is an effective keratolytic agent for the removal of hyperkeratotic debris. It is also used in combination with salicylic acid in the treatment of ichthyosis, psoriasis, keratosis pilaris and hypertrophic lichen planus. 

Salicylic acid has been extensively used in dermatologic therapy as a keratolytic agent. The mechanism by which it produces its keratolytic and other therapeutic effects is poorly understood. The drug may solubilize cell surface proteins that keep the stratum corneum intact, thereby resulting in desquamation of keratotic debris. Salicylic acid is keratolytic in concentrations of 3-6%. In concentrations greater than 6%, it can be destructive to tissues. 

Propylene glycol is used extensively in topical preparations because it is an excellent vehicle for organic compounds. It has been used alone as a keratolytic agent in 40-70% concentrations, with plastic occlusion, or in gel with 6% salicylic acid. 

As a humectant, urea is used in concentrations of 2-20% in creams and lotions. As a keratolytic agent, it is used in 20% concentration in diseases such as ichthyosis vulgaris, hyperkeratosis of palms and soles, xerosis, and keratosis pilaris. Concentrations of 30-50% applied to the nail plate have been useful in softening the nail prior to avulsion. 

Keratolytic agents -salicylic acid derivatives [SALICYLIC ACID AND RELATED COMPOUNDS] (Vol 21)... 

Salicylic acid was chemically synthesized in 1860 and has been extensively used in dermatologic therapy as a keratolytic agent. It is a white powder quite soluble in alcohol but only slightly soluble in water. 

Propylene glycol is an effective keratolytic agent for the removal of hyperkeratotic debris. 

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