Salicylic acid patient preparation

Salicylism, or salicylic acid toxicity, is characterized by rapid breathing, tinnitus, hearing loss, dizziness, abdominal cramps, and central nervous system reactions. It has been reported with 20% salicylic acid applied to 50% of the body surface, and it has also been reported with use of 40 and 50% salicylic acid paste preparations [7]. The author has peeled more than 1,000 patients with the current 20 and 30% marketed ethanol formulations and has observed no cases of salicylism. 

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. 

Sulfur, resorcinol, benzoyl peroxide, or salicylic acid Caut ous y use concomitant topical medications because of possible interactions with tretinoin. Significant skin irritation may result. It also is advisable to rest a patient s skin until the effects of such preparations subside before use of tretinoin is begun. 

Salicylism and death have occurred following topical application. In an adult, 1 g of a topically applied 6% salicylic acid preparation will raise the serum salicylate level not more than 0.5 mg/dL of plasma the threshold for toxicity is 30-50 mg/dL. Higher serum levels are possible in children, who are therefore at a greater risk for salicylism. In cases of severe intoxication, hemodialysis is the treatment of choice (see Chapter 58). It is advisable to limit both the total amount of salicylic acid applied and the frequency of application. Urticarial, anaphylactic, and erythema multiforme reactions may occur in patients who are allergic to salicylates. Topical use may be associated with local irritation, acute inflammation, and even ulceration with the use of high concentrations of salicylic acid. Particular care must be exercised when using the drug on the extremities of patients with diabetes or peripheral vascular disease. 

A patient asks for your advice about a verruca that she has had for over a year. She has tried three preparations containing salicylic acid prescribed by her general practitioner and none has worked. She is now absolutely fed up and asks what she can do. What would your advice be ... 

Salicylic acid is a mild irritant and similar precautions should be adopted as for benzoyl peroxide. Preparations are applied twice or three times a day. Salicylic acid is readily absorbed through the skin and excreted slowly, and salicylate poisoning can occur if preparations are applied frequently, in large amounts and over large areas. Patients who are sensitive to aspirin should avoid these preparations. 

Bismuth compounds have been used to treat a variety of gastrointestinal diseases and symptoms for centuries, although their mechanism of action remains poorly understood. Pepto-Bismol (bismuth subsalicylate is an over-the-counter preparation estimated to be used by 60% of American households. It is a crystal complex consisting of trivalent bismuth and salicylate suspended in a mixture of magnesium aluminum silicate clay, hi the low pH of the stomach, the bismuth subsalicylate reacts with hydrochloric acid to form bismuth oxychloride and salicylic acid. While 99% of the bismuth passes unaltered and unabsorbed into the feces, the salicylate is absorbed in the stomach and small intestine. Thus, caution should be used in patients taking salicylates for other indications. 

Keratolytics are available in a multitude of formulations for treating skin diseases. Prolonged use of salicylic acid preparations over large areas, especially in children and patients with renal and hepatic impairment, can result in salicylism. Irritation is a common side effect with higher concentrations. Lactic acid (Lac-hydrin, others) is an emoUient that contains 12% lactic acid, which is an effective moisturizer indicated for the treatment of xerosis and ichthyosis vulgaris. 

It is of interest to point out here that Hangarter had recognized the importance of copper in his preparation of Cu(II)-(salicylate). It was known that in order to achieve the same therapeutic success with only intravenous salicylate therapy, a serum level of at least 25 mg/100 ml was necessary. To achieve this concentration of unbound salicylate, these patients would have had to have been given more than 12 g of salicylic acid, six Permalon injections, divided... 

Another active principle soon extracted from plants was salicylic acid. Willow and salicin, in extensive competition with Cinchona bark and quinine, never became a very popular treatment for fever or rheumatic symptoms due to a Scottish physician, Thomas John MacLagan (1838-1934), who launched salicin in 1876. His rationale was inspired by the Paracelse signature s theory willow is growing in moisture along rivers and lakes, an ideal place to be crippled with rheumatism. Raffaele Piria (1815-1865), after isolation of salicylaldehyde (1839), in Spireae species, prepared salicylic acid from salicin. This acid was easier to use and was an ideal step before future synthesis. His structure was closely related to that of benzoic acid, an effective preservative usefiil as an intestinal antiseptic, for instance in typhoid fever. Patients treated with salicylic acid were dying as frequently as untreated patients, but without fever. 

Impurities contaminating commercial aspirin preparations could be responsible for appearance of urticaria and angioedema in some patients (de Weck 1971 Bundgaard and de Weck 1975). These contaminants include acetylsalicylic anhydride, acetylsalicylic salicylic acid and cw-disalicylide. A rapid and convenient colorimetric method has been described recently for the quantitative determination of these immunogenic impurities in aspirin (Bundgaard 1976). 

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. 

The patient consulted us regarding macular acne scarring. After preparation with sunscreens and 10% glycolic acid lotion at night for 2 weeks, she was treated with 30% salicylic acid peels once a month for 3 consecutive months. Figure 13.6 shows the remarkable improvement of skin texture and macular spots. 

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