Flushing, pruritus and hypotension during a rapid intravenous vancomycin infusion in a 45-year-old man

A 45-year-old man was admitted to the orthopaedic ward with osteomyelitis of the right tibia. His medical history included hypertension, treated with lisinopril 10 mg once daily. He had no known drug allergies. On admission, he was prescribed intravenous vancomycin 1.5 g every 12 hours for a suspected MRSA infection, and intravenous ceftriaxone 2 g once daily for empiric gram-negative coverage. He also received oral pantoprazole 40 mg once daily for gastroprotection.

On the morning of day 3, he took his usual lisinopril at 07:00. At 08:00, the vancomycin infusion was started. The prescribed rate was for 1.5 g over 60 minutes, but the infusion was mistakenly run over 25 minutes. Fifteen minutes after the start of the infusion, the patient complained of flushing, intense pruritus over his face and trunk, and a feeling of faintness. Physical examination showed widespread erythema over the face, neck and upper chest, and he was anxious. His blood pressure was 85/48 mmHg, and his heart rate was 110 beats per minute. An ECG showed sinus tachycardia, and blood tests taken at the time were unremarkable.

The infusion was stopped immediately. The patient was given 500 mL of intravenous crystalloid over 15 minutes. His symptoms resolved within 30 minutes, and his blood pressure returned to 128/76 mmHg. The erythema faded. Ceftriaxone had been given the previous evening and was not being infused at the time of the reaction. The patient had not previously experienced a similar reaction. No rechallenge was attempted because of the sustained hypotension.