Adrenaline: A Lifeline for Rapid Drug Desensitization in Hypersensitive Patients

Chemotherapeutic agents (CMTs) and monoclonal antibodies (mAbs) are common causes of drug allergy, which is often managed using rapid drug desensitization (RDD). Despite its effectiveness, RDD can be hampered by severe breakthrough reactions (BTRs), potentially leading to failure of the procedure. Objective: To evaluate the usefulness and safety of adrenaline infusion (AI) as an adjuvant during RDD in patients who experience severe drug hypersensitivity reaction (DHR) during standard desensitization protocols.

Retrospective observational study, analyzing data from patients who underwent RDD to CMTs or mAbs in a tertiary hospital from January 2015 to June 2024. We included patients who required AI to safely achieve RDD after a severe initial DHR or failure of a standard RDD protocol due to repeated DHRs. Comorbidities, adrenaline doses, and adverse events (AEs) were assessed.

RDD with AI was administered in 42 patients. Of these, 77% (n=32) were women, and the mean age was 57 years. The most frequently involved drugs were platinum salts (58%), mAbs (26%), and taxanes (14%). A total of 151 RDDs were performed with AI. Skin tests were positive in 69% of patients. The most frequent initial BTR (65%) was moderate or severe anaphylaxis. The most common AEs induced by AI were tremor (14%) and tachycardia (7%), which resolved after reducing the AI infusion rate. The median (IQR) cumulative dose of adrenaline administered throughout the RDD procedure was 0.76 mg (0.4-1.2mg), with a median infusion rate of 8 mL/h (4- 15ml/h), and median maximum AI rate of 3.33 μg/min (2-5.3 μg/min).

AI is a useful and safe therapeutic tool for selected high-risk desensitization procedures, mitigating severe DHR with mostly minor AEs.