Contact dermatitis antihistamines

After treatment, use topical corticosteroids to decrease contact dermatitis, antihistamines for pruritus pruritus may continue for 4-6 wk... 

Whether due to their antihistaminic activity or their sedative side effects, pruritus caused by contact dermatitis can be relieved with the use of sedating oral antihistamines such as... 

Hj antihistamines are clinically used in the treatment of histamine-mediated allergic conditions. Specifically, these indications may include allergic rhinitis, allergic conjunctivitis, allergic dermatological conditions (contact dermatitis), pruritus (atopic dermatitis, insect... 

Irritant or allergic contact dermatitis is eczematous and is often caused by antimicrobials, local anaesthetics, topical antihistamines, and increasingly commonly by topical corticosteroids. It is often due to the vehicle in which the active drug is applied, particularly a cream. 

Although antihistamines are often used in the treatment of allergic conditions, topical use often produces skin sensitization and subsequent contact dermatitis (90,91). This effect occurs more often with the use of ethylenedia-mines and phenothiazines the latter also produce photo-allergic cutaneous reactions (92). A photoallergic contact dermatitis followed by a persistent light reaction was attributed to topical dioxopromethazine hydrochloride incorporated into a gel in a woman with periocular... 

Allergic contact dermatitis, characterized by erythema, palpable edema, and raised borders, was attributed to benzyl alcohol (2). In this case, the benzyl alcohol was present as a preservative in an injectable solution of sodium tetradecyl sulfate, a sclerosing agent used for the treatment of varicose veins. The author provided a hst of 151 injectable formulations (48 for subcutaneous administration) that contained benzyl alcohol as a preservative in the range 0.5-2.0%. The list included hormones and steroids, antihypertensive drugs (reserpine), vitamin formulations (vitamins B12 and Bg), ammonium sulfate, antihistamines, antibiotics, heparin (17 brands), tranquillizers, and sclerosing agents (sodium morrhuate and sodium tetradecyl sulfate). 

Szolar-Platzer C, Maibach HI. Allergic contact dermatitis to topically apphed antihistamines. Dermatosen 1996 44 205-12. 

They also are included in multidrug treatment protocols for eradication of H. pylori in treatment of peptic ulcers and before surgery to prevent aspiration pneumonitis. Like Hi antihistamines, H2 antihistamines are inverse agonists that block the basal level of activity at this receptor. Combinations of Hi and H2 antihistamines are useful in idiopathic urticaria not responding to Hi antihistamines alone and in itching and flushing of anaphylaxis, pruritis, and contact dermatitis. 

At the first sign of contact dermatitis, clean the skin area immediately. Patch testing may be needed to determine the causative factor. Apply wet dressings containing Burow s solution (aluminum acetate), lotions such as calamine that contain zinc oxide, calcium hydroxide solution, and glycerin. Calamine lotion may contain the antihistamine diphenhydramine and is used primarily for plant irritations. If itching persists, antipraritics (topical or systemic diphenhydramine [Benadryl]) may be used. Topical antipraritics should not be applied to open wounds or near the eyes or genital area. 

Allergic contact dermatitis is one of the commonest allergic skin diseases caused by drugs. The main causes are attributed to the group of antibiotics, chemothera-peutics, local analgetics, antirheumatics, antimycotics, disinfectants, antihistamin-ics, as well as ingredients of the vehicles (preservatives, antioxidants, and others). Further details will be found elsewhere in this book (Chap. 13). 

At the onset, it must be emphasized that although the systemic administration of the antihistamines rarely engenders sensitization, topical applications such as antihistamines not infrequently produce allergic contact sensitivity. Once the patient is sensitized by topical application of the antihistamine, an eczematous contact dermatitis may occur from the antihistamine or from immunochemically related compounds. As a rule the systemic administration of an antihistamine to which there has been topical sensitization will not only reproduce the original allergic eczematous contact dermatitis, but at times a generalized dermatitis will occur with a resulting exfoliative dermatitis (Fisher 1976 b). In some instances, the systemic eczematous contact dermatitis is accompanied by urticarial elements. 

Individuals who have become sensitized by topically applied diphenhydramine can acquire a systemic eczematous contact dermatitis when diphenhydramine or any of the other ethanolamines listed in Table 5 is ingested or injected (Fisher 1973 It is not generally realized that dimenhydrinate (Dramamine) is an ethanol-amine (the chlorotheophylline salt of the antihistaminic agent diphenhydramine). Dimenhydrinate contains between 53% and 56% diphenhydramine and therefore should not be administered to any individual with allergic hypersensitivity to the ethanolamine group of antihistamines. 

Although topical phenothiazine antihistamine preparations such as promethazine hydrochloride (Phenergan) cream are no longer used in the United States, such topical antihistamine preparations are still widely used in Europe. Individuals who have become sensitized by such topical phenothiazine antihistamines often suffer a flare of the dermatitis when a phenothiazine antihistamine is taken, i.e., a systemic eczematous contact dermatitis. In addition, many individuals acquire allergic sensitization to various phenothiazine drugs which show cross-reactions with the phenothiazine antihistamines. Table 6 lists the phenothiazine antihistamine compounds. 

The phenothiazine drugs listed in Table 7 are all capable of cross-reacting with the phenothiazine antihistamines, and all of these compounds are potential photosensitizers (Lewis and Sawicky 1955). Often a photoallergic reaction occurs in combination with the allergic eczematous contact dermatitis. The systemic administration of the phenothiazine drugs shown in Table 7 may produce an eczematous contact dermatitis medicamentosa in individuals sensitized by such topical exposure. Cross-reactions readily take place between these phenothiazines and the related antihistamines (Mitchell and Ongley 1972). 

Medical and nursing personnel who inject these phenothiazine drugs or who handle phenothiazine tablets which are given to patients, and those who come into contact with the compounds in the pharmaceutical industry readily acquire allergic eczematous contact dermatitis of the hands from such exposure the dermatitis may flare when a phenothiazine antihistamine is given (Calnan et al. 1962). Since chlorpromazine, in particular, is excreted almost unchanged in the urine, sensitized nurses and orderlies who handle unwashed linen may experience flares. 

The same phenothiazines or closely related compounds which are used as psychotropic drugs or as sedatives in humans are used by veterinarians and farmers as insecticides and anthelmintics for animals and birds. Table 8 lists the commercial phenothiazine insecticides and wormers used by veterinarians. Many individuals in these professions have acquired allergic contact dermatitis, photoallergic reactions, or both by spraing such phenothiazines for insect control or feeding these compounds as wormers. Such individuals must avoid using phenothiazine antihistamines because of the likelihood of producing flares of the phenothiazine dermatitis. 

Thach BT, Chase TN, Bosma JF (1975) Oral facial dyskinesia associated with prolonged use of antihistaminic decongestant. N Engl J Med 293 486-490 Van Hecke E (1975) Ethylenediamine sensitivity from exposure to epoxy resin hardeners and mycolog cream. Contact Dermatitis 1 344-348 Vickers CFH (1961) Dermatitis medicamentosa. Br Med J 1 1366-1368... 

Uses Antihistamine drug for relief of symptoms of head colds, common flu, sinus congestion, hay fever to elevate blood pressure treatment of allergic reactions of skin and mucous membranes, e.g., acute urticaria, atopic dermatitis, allergic rhinitis for temporary relief of itching skin, e.g., atopic dermatitis, contact dermatitis, pruritus, and insect bites jaundice Manuf./Distrib. ICN Biomed. Research Prods. http //www.icnbiomed.com Ruger http //www.rugerchemical.com Spectrum Quality Prods. 

Aside from future avoidance of direct skin contact with the offending solvents, irritant and allergic contact dermatitis and chemical burns are treated according to general dermatological principles. Due to the risk of anaphylaxis, patients with verified immunological contact urticaria should avoid further contact. The extent to which antihistamines are beneficial in cases of contact urticaria to solvents is not known. 

Contact allergy to topically applied aluminium compounds is rare but skin sensitization has been described (54). In one case the use of a cream for acne and hyperpigmentation was followed by dermatitis, and patch tests were positive to both aluminium sulfate and aluminium chloride. A more typical antecedent of sensitization is the injection of aluminium-adsorbed vaccines, and such patients may present with a granulomatous nodule at the site. Mixed contact sensitivity to nickel and aluminium has been reported to respond to antihistamine therapy (55). 

It is sometimes recommended that persons subject to allergy should not be allowed to come in contact with epoxy resin systems. This would be an improbably measure to observe, it must be kept in mind that exposure to epoxy resin systems cannot cause anything but skin dermatitis. There has been absolutely no evidence of any carcinogenic effect from contact with these systems. Where slight irritations occur, desensitization should first be attempted. If eczema occurs, standard medical treatment should be provided. Antihistamine drugs may be used only to reduce itching. In severe cases, such as in the second stage of dermatosis, cortisone ointments have been used successfully to relieve the symptoms. It should be kept in mind that if protective measures are scrupulously observed, incidents of dermatoses from epoxy resin systems can be kept to a very low minimum. There is no reason for any concern in the use of these systems in the construction industry. 

Sensitisation to the topical antifungal agent, Mycanodin is difficult to quantitate. The active antifungal is 3-(2-hydroxy-5-chlorophenyl)pyrazole and this can cause contact allergic dermatitis and photoallergic reactions (Fig. 4 Burckhardt et al. 1968). The same authors showed, however, that an antihistamine co-formu-... 

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