Contact allergens drugs

Antifungal drugs are comparatively rare contact allergens in the anogenital region in relation to their widespread use. Clotrimazole and nystatin are preferred. In the study of the IVDK, patch tests with clotrimazole were performed in only 272 patients, leading to five positive reactions (15). In the UK study on anogenital dermatosis, five women out of... 

Except for contact dermatitis, the route of administration appears to be of little importance in determining the type of hypersensitivity and clinical symptoms produced. Application of allergenic drugs to the skin is usually associated with a high incidence of sensitization (favorable conditions for the formation of conjugates ), whereas the oral route appears to be less likely to foster sensitization. Allergic reactions occur in about 2.5% of patients given penicillin G parenterally, in 5%... 

The incidence of contact sensitivity to 12 topically applied drugs in the relation to the frequency with which they are used in Warsaw was studied by Rudzki and Zakrzew-ski(l ). For this purpose 200,000 pharmaceutical prescriptions filled in 16 Warsaw pharmacies were analysed. The ratio of sensitive subjects to the number of prescriptions of each drug was calculated. This index of sensitization was calculated on the basis of prescribed ointments, creams and pastes etc. (Table 1). The high ratio of sensitization to Balsam of Peru is attributed to the use of suppositories. In the case of coal tar the high sensitization index may be due to non-specific irritation. In another study, Ebner (59 ) reports that Balsam of Peru was the most frequently encountered contact allergen in children and young persons. 

There are two main sensitization reactions-immedi-ate and delayed hypersensitivity. Immediate type hypersensitivity is the result of antibody-allergen interaction occurring in the skin the reaction that develops is known as allergic contact urticaria. Delayed type hypersensitivity is the result of cell-mediated immunity and is the most frequently reported side effect of topical drugs. Both epidermal and dermal cells play pivotal roles in irritation and sensitization. Keratinocytes... 

Phenylephrine was the drug that most often caused sensitization in patients with contact allergy after the application of mydriatic eye-drops. Since several eye-drops are often used in the same patient, it is always important to find out which drug or preservative is the allergen (10-13). 

The second most frequent drug allergy is the T cell-mediated hypersensitivity. Chemicals that come in contact with the skin can induce contact hypersensitivity reactions. Hapten-specific T cells are guided to the site of allergen contact, most probably due to continued or subsequent exposure of the site to the allergen,10 and result in immune-mediated skin reactions through the release of, for example, cytokines or chemokines. 

Eczema is a localized inflammatory reaction in the skin that has several possible causes. It can be a reaction to contact with chemicals including some drugs, metals or allergens. 

Nater JP, De Groot AC (1978) Drugs used on the skin. In Dukes MNG (ed) Meyler s side effects of drugs, 9th edn. Excerpta Medica, Amsterdam London New York, pp 234-264 Nilsson DC (1960) Sources of allergenic gums. Ann Allergy 18 518-524 Nordquist BC, Mehr K (1977) Allergic contact dermatitis to retinoic acid. Contact Dermatitis 3 55-56... 

In patients sensitive to p-phenylenediamine, the intake of certain azo dyes caused a flare of their dermatitis (Baer and Leider 1949 Sidi and Arouete 1959). The cross-reactivity between various allergenic dyes has been tested by Weirich (1961). Contact dermatitis to azo dyes employed in the textile and leather industries was described by Sultrmond et al. (1967). Roeleveld and van Ketel (1976) reported a patient with a dermatitis caused by a yellow shirt. The patch test was positive to the azo dye, tartrazine. Interestingly the eruptions worsened after drinking orange juice which could have contained tartrazine. Calnan (1976) found positive patch tests to quinazoline yellow which is used in foods, drugs, and cosmetics. Grater (1976) reported 133 positive reactions to a set of such dyes. 

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