Affiliation:
1. Department of Dermatology, Venereology and Leprosy, Dr. Radhakrishnan Government Medical College, Hamirpur, Himachal Pradesh, India,
Abstract
Dermatitis medicamentosa or contact dermatitis to topically applied medicaments, active ingredients or excipients, is encountered frequently in clinical practice and should be suspected in patients showing resistance to treatment despite adequate therapy and in patients, who complain of intolerance to a particular treatment. Topical corticosteroids are prescribed mostly in dermatology for their anti-inflammatory, antiproliferative, and immunosuppressive actions to treat various inflammatory dermatoses. These may act as allergens and produce immunoglobulin E-mediated immediate hypersensitivity (anaphylaxis, urticaria, angioedema, bronchospasm, vomiting, and cardiovascular collapse) or T-cell-mediated allergic contact dermatitis (ACD). Although it occurs less often and is not life threatening, ACD negatively impacts the quality of life by worsening preexisting dermatitis. The prevalence of hypersensitivity to these allergens varies across regions and periods of time depending on the clinical practice, prescribing habits, and types of cases studied. Over-the-counter availability of corticosteroids in multiple formulations in recent years may further compound the problem due to their indiscriminate and extensive use. Although about one-third of all cases of contact dermatitis are initiated or perpetuated by topical medicaments, the occurrence of contact dermatitis due to corticosteroids remains undersuspected. This is perhaps due to their anti-inflammatory and immunosuppressive properties that make it difficult to doubt and prove contact sensitivity that may be from a corticosteroid itself or to the additives and vehicles in the formulation. Patch testing can help identify the culprit agents in ACD but early diagnosis depends on clinical suspicion. Sensitization in contact dermatitis exhibits cross-reactivity patterns based on corticosteroid structure. Clinicoepidemiological presentation, evaluation, and management aspects of contact hypersensitivity reactions to corticosteroids are reviewed.