Plasters salicylic acid

Salicylic acid (1) is not employed internally as an analgesic due to its local irritating effect on the gastrointestinal tract. It is employed externally on the skin, where it exerts a slight antiseptic action and a marked keratolytic action. The latter property makes salicylic acid a beneficial agent in the local treatment of warts, corns, fungous infections, and certain forms of eczematoid dermatitis. Tissues cells swell, softer, and ultimately desquamate. Salicylic acid is applied as a 2 to 20% concentration in collodion, lotions, or ointments, and as a 10 to 40% concentration in plasters. Salicylic acid plaster is used for the destructive effect of salicylic acid on hardened, keratinized tissue. The so-called corn plaster are typical. 

American Pharmacy (1856), that the spreading of plasters which was formerly an important part of the business of the apothecary has now... been monopolized by manufacturers who bring machinery to their aid. The only plaster which still finds significant use today is Salicylic Acid Plaster, United States Pharmacopeia— the common corn plaster (also see Plasters, adhesive, and Plasters,... 

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. 

Salicylic Acid Self-adhesive Plaster, B.P.C. Suitable cloth spread evenly with a self-adhesive plaster mass containing 20 per cent of salicylic acid. 

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