European Medical Journal Allergy & Immunology (Aug 2016)
A Review Of Drug Allergies: Diagnosis and Management
Abstract
Drug allergy, in clinical practice, includes a wide spectrum of immunologically-mediated hypersensitivity reactions, also called drug hypersensitivity reactions (DHRs). It can present with diverse clinical manifestations and can have various underlying pathophysiological mechanisms. Drug allergies often require a number of investigations and this can sometimes lead to a delay in treatment of the original disease. Drug allergy can affect quality of life too. It does contribute to significant morbidity and even mortality which is largely avoidable. Meticulous relevant details in history and clinical examination are often rewarding in arriving at the correct diagnosis. Patients with underlying chronic airways diseases such as asthma may benefit from skin tests and graded allergen challenges. Procedures to induce drug tolerance are sometimes helpful in the drug allergy management. Likelihood of cross-reactivity among drugs should be taken into account while choosing alternative medication. Measures for drug allergy reactions are mostly supportive and usually include topical corticosteroids and oral antihistamines. However, systemic corticosteroids may be required in severe DHRs along with adrenaline in the event of anaphylaxis. The most effective approach towards the problem of ‘drug allergy’ is discontinuing or avoiding the offending culprit. Procedures to induce drug tolerance may be considered as a temporary measure toward tolerance to the offending drug if there is no alternative available. This article aims to provide a simple clinical review of drug allergy and plan of action for the diagnosis as well as management of some of the most common DHRs, such as allergies to acetylsalicylic acid, non-steroidal anti-inflammatory drugs, penicillins, sulpha drugs, cephalosporin, contrast media in imaging procedures, anaesthetic agents, and vaccines.
