Psoriasis salicylic acid

Salicylic acid is used to treat acne, warts, dandruff, psoriasis, and similar conditions. In the treatment of acne, it slows the shedding of skin cells in hair follicles, so they do not clog the pores and cause pimples. It also has a keratolytic effect—it causes dead skin cells to slough off— which removes the top layer of skin and clears existing pore clogs. 

Like salicylic acid, it is also used to treat warts, psoriasis, and other skin conditions. 

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). 

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 USP, EP, and other pharmacopeia grades are used medically as antiseptic, disinfectant, antifungal, and keratolytic agents. Salicylic acid is formulated in lotion or ointment formulations for the treatment of dandruff, 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 salicylic acid solutions or suspensions to remove warts and corns. In more dilute form, salicylic acid preparations have found use in dandruff and eczema treatment. Salicylic acid has been considered and found effective by the Advisory Committees to the FDA in various over-the-counter (OTC) drug regulated uses. Among these are acne products, dermatitis, dry skin, dandruff and psoriasis products, and foot care products (24). 

Propylene glycol is used under polyethylene occlusion or with 6% salicylic acid for the treatment of ichthyosis, palmar and plantar keratodermas, psoriasis, pityriasis rubra pilaris, keratosis pilaris, and hypertrophic lichen planus. 

Urea is a hydrating agent (a hydrotrope) used to treat scaling conditions such as psoriasis, ichthyosis, and other hyperkeratotic skin conditions. Applied in a water-in-oil vehicle, urea alone or in combination with ammonium lactate hydrated stratum corneum and improved barrier function when compared to the vehicle alone in human volunteers in vivo [45], Urea also has keratolytic properties, usually when combined with salicylic acid for keratolysis. The somewhat modest penetration-enhancing activity of urea probably arises from a combination of increasing stratum corneum water content (water is a valuable penetration enhancer) and through the keratolytic activity. 

The major risk resulting from topical treatment of psoriasis with salicylic acid is the potential chronic or acute systemic intoxication with the symptoms of burning of oral mucosa, frontal headache, CNS symptoms, pH deviation (metabolic acidosis), tinnitus, nausea, vomiting, and gastric symptoms.28-30 These symptoms may occur in topical treatment of large body surfaces, especially in children.31-33 Even lethal cases have been reported.34,35 Therefore, a concentration higher than 10%, and an application on larger surfaces especially in children are not suitable. Salicylic acid should not be applied to more than 20% of the body surface area.13 It should be noted that some topical treatments of psoriasis such as calcipotriol are inactivated by salicylic acid.36... 

Dithranol in combination with urea is widely used in psoriasis to improve the clinical efficacy, to minimize the dithranol concentration, to achieve the desired effect, to shorten the contact, to get a better hydration of the stratum corneum, and to decrease the proliferation rate of the keratinocytes. Gabard and Bieli showed an increased keratolytical effect of salicylic acid by adding 10% urea.54 Hagemann and Proksch55 showed in 10 patients with psoriasis under a 2-week treatment with a 10% urea ointment increased stratum corneum hydration, a small decrease in TEWL, a reduction in epidermal thickness (-29%), and a decreased epidermal proliferation (-51%). The altered expression of involucrin and cytokeratins as marker for epidermal proliferation was partially reversed.55... 

Arnold, W., F. Trinnes, and I. Schroeder, Skin resorption of salicylic acid in psoriasis patients and persons with healthy skin. Beitr. Gerichtl. Med., 1979,37 325-8. 

Pullmann, H., K.J. Lennartz, and G.K. Steigleder, The effect of salicylic acid on epidermal cell proliferation kinetics in psoriasis. Autoradiographic in vitro-investigations (author s transl). Arch. Dermatol. Forsch, 1975,251 271-5. 

Runne, U., Anthralin-salicylic acid therapy of psoriasis. Cignolin-salicylic acid-vaseline treatment and Lasan paste in a right-left comparison. Hautarzt, 1974, 25 199-200. 

Pec, J., M. Strmenova, E. Palencarova, R. Pullmann, S. Funiakova, P. Visnovsky, J. Buchanec, and Z. Lazarova, Salicylate intoxication after use of topical salicylic acid ointment by a patient with psoriasis. Cutis, 1992, 50 307-9. 

Vonweiss, J.F. and W.F. Lever, Percutaneous salicylic acid intoxication in psoriasis. Arch. Dermatol., 1964, 90 614-9. 

Topical corticosteroids are usually given in combination with other topical treatments for the treatment of chronic plaque psoriasis. Sensitive areas, such as the face, should be treated with a mild corticosteroid and other areas, such as the scalp, with moderate to potent corticosteroids. In general, use should be maintained as early improvements in the condition are not maintained if use is halted. Such a pattern of use may worsen the condition, possibly causing a deterioration of the condition to unstable forms, such as erythrodermic or pustular psoriasis. Co-administration of topical medicaments usually involves alternating administration of each product. Scalp psoriasis is normally treated with softening emollients in combination with salicylic acid with coal tar or sulphur. 

Antipsoriatic agents are used to treat psoriasis, a serious chronic skin condition characterized by scaly pink patches. A number of agents may be used in treatment, but there is no cure. KERATOLYTic (desquamating) AGENTS are used extensively, including coal tar, dithranol, etretinate, ichthammol and salicylic acid also retinoids (see below) and corticosteroids. 

Keratolytics (salicylic acid, sulfur) Loosens psoriasis scales... 

Salicylic acid (3) has kertolytic properties and is applied topically in the treatment of hyperkeratic and scaling skin conditions such as dandruff, ichthyosis, and psoriasis. Initially a concentration of about 2% is used, increased to about 5% if necessary. It is often used in conjunction with many other agents, such as benzoic acid, coal tar, resorcinol, and sulpher. Salicylic acid is also used in the form of a paint in a collodion basis (10 to 14%) or as a plaster (20 to 250%) to destroy warts or corns. It also possesses fungicidal properties and is used topically in the treatment of such fungal skin infections as tinea. 

Psoriasis preparations may contain salicylic acid, a rare sensitizer (five cases (Rudzki and Koslowska 1976). Four of the patients used salicylic acid 2% in alcohol. They tolerated oral acetylsalicylic acid (aspirin) without causing exacerbation or relapse of the dermatitis. 

Its topical use lies mainly in the treatment of psoriasis, as a keratolytic agent to descale plaques (1-20% ointment). Salicylism is the term used to describe the toxicological state that occurs following percutaneous absorption of salicylic acid (Von Weis and Lever 1964). Intoxication depends largely on the total body area over which the salicylic acid is applied (Brubacher and Hoffman 1996). Formerly, salicylic acid also had a reputation as an anti-mycotic (3% in Whitfield ointment). Contact allergy was reported (Goh and Ng 1986). 

Viljanto J (1980) Disinfection of surgical wounds inhibitive of normal wound healing. Arch Surg 115 253 Von Weis JF, Lever WF (1964) Percutaneous salicylic acid intoxication in psoriasis. Arch Dermatol 90 614 Wahlberg JE (1962) Two cases of hypersensitivity to quaternary ammonium compounds. Acta Derm Venereol 42 239 White IR (1995) Phototoxic and Photoallergic reactions. In Rycroft RJG, Menne T, Frosch PJ (eds) Textbook of contact dermatitis. Springer, Berlin Heidelberg New York, p 84 Whitehead PN (1988) Dermatitis from crystal violet. Contact Dermatitis 19 141-142... 

Toxic systemic effects have been reported for salicylic acid, resorcinol, lindane or mercury substances. These effects are related to the substance, the amount of preparation and the body surface area to which it is applied, the skin conditions and duration of treatment. Symptoms for systemic intoxications are for example headache, nausea and vomiting, convulsions, fall in blood pressure, kidney damage or metabolic acidosis. Apart from salicylic acid the mentioned substances are no longer used because of these systemic adverse effects and the limited therapeutic significance in cutaneous preparations. Especially infants and toddlers are susceptible for systemic adverse effects because their skin is thinner. Additionally, the relative body surface area in relation to body contents in children is larger than in adults. For salicylic acid in infants and toddlers the only indication is psoriasis. It should be used in low concentrations and on a limited body surface area. 

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