MS-2160

A 25-year-old male with a history of cystic fibrosis and recurrent chest infections is being started on prophylactic antibiotics due to multiple hospitalisations for severe community-acquired pneumonia. The consultant has chosen chloramphenicol as the antibiotic of choice, given the patient’s history of growing bugs resistant to broad-spectrum antibiotics. What parameter should be regularly monitored in this patient after starting the new medication?