Successful desensitization to ribavirin in a patient with chronic hepatitis C

Desensitization for the prevention of drug hypersensitivity reactions

Drug desensitization is the temporary induction of tolerance to a sensitized drug by administering slow increments of the drug, starting from a very small amount to a full therapeutic dose. It can be used as a therapeutic strategy for patients with drug hypersensitivity when no comparable alternatives are available. Desensitization has been recommended for immunoglobulin E (IgE)-mediated immediate hypersensitivity; however, its indications have recently been expanded to include non-IgE-mediated, non-immunological, or delayed T cell-mediated reactions. Currently, the mechanism of desensitization is not fully understood. However, the attenuation of various intracellular signals in target cells is an area of active research, such as high-affinity IgE receptor (FcεRI) internalization, anti-drug IgG4 blocking antibody, altered signaling pathways in mast cells and basophils, and reduced Ca2+ influx. Agents commonly requiring desensitization include antineoplastic agents, antibiotics, antituberculous agents, and aspirin/nonsteroidal antiinflammatory drugs. Various desensitization protocols (rapid or slow, multi-bag or one-bag, with different target doses) have been proposed for each drug. An appropriate protocol should be selected with the appropriate concentration, dosage, dosing interval, and route of administration. In addition, the protocol should be adjusted with consideration of the severity of the initial reaction, the characteristics of the drug itself, as well as the frequency, pattern, and degree of breakthrough reactions.

Diagnosis and management of the drug hypersensitivity reactions in Coronavirus disease 19: An EAACI Position Paper

Coronavirus disease 2019 (COVID-19), a respiratory tract infection caused by a novel human coronavirus, the severe acute respiratory syndrome coronavirus 2, leads to a wide spectrum of clinical manifestations ranging from asymptomatic cases to patients with mild and severe symptoms, with or without pneumonia. Given the huge influence caused by the overwhelming COVID-19 pandemic affecting over three million people worldwide, a wide spectrum of drugs is considered for the treatment in the concept of repurposing and off-label use. There is no knowledge about the diagnosis and clinical management of the drug hypersensitivity reactions that can potentially occur during the disease. This review brings together all the published information about the diagnosis and management of drug hypersensitivity reactions due to current and candidate off-label drugs and highlights relevant recommendations. Furthermore, it gathers all the dermatologic manifestations reported during the disease for guiding the clinicians to establish a better differential diagnosis of drug hypersensitivity reactions in the course of the disease.

Antimicrobial Desensitization: A Review of Published Protocols

Antimicrobial desensitization represents a last-line option for patients with no alternative therapies, where the benefits of this intensive process must outweigh the potential harm from drug exposure. The goal of antimicrobial desensitization procedures is to establish a temporary state of tolerance to drugs that may otherwise cause hypersensitivity reactions. While no universal antimicrobial desensitization protocols exist, this review critically analyzes previously published desensitization protocols. The purpose of this review is to provide a greater insight for clinicians and institutions to ensure desensitization procedures are efficacious while minimizing potential for patient harm. With an increasing rate of antimicrobial resistance and the critical need to preserve antimicrobial agents, desensitization may represent another option in our antimicrobial stewardship toolkit.