Remimazolam-induced anaphylaxis: a case series and clinical implications

Remimazolam is a short-acting benzodiazepine used for general anesthesia.Although generally considered safe, rare cases of anaphylaxis have been reported.We present four cases of suspected remimazolam-related anaphylaxis during general anesthesia.All patients were male and experienced acute symptoms, including hypotension, flushing, bronchospasm, or cardiac arrest, within 5-15 min of remimazolam administration.Two patients had elevated serum tryptase levels, whereas skin tests for remimazolam and midazolam were negative.All patients had prior uneventful exposure to other anesthetic agents, and remimazolam was the only newly introduced drug.The symptoms were refractory to vasopressors but improved with prompt epinephrine administration.All patients recovered fully with ICU care.Remimazolam-related anaphylaxis may present atypically, often without cutaneous or respiratory signs.Early recognition and prompt use of epinephrine are critical.Clinicians should be vigilant during remimazolam administration, even at standard doses.