Background Linezolid is an antibiotic used for the treatment of serious infections caused by gram positive bacteria. Although first approved for skin infections, its use includes empiric treatment of infections usually caused by linezolid sensitive bacteria.

Purpose To describe, analyse and optimise the use of linezolid in a university hospital. To study new susceptible optimisation points.

Material and methods This was a retrospective observational study (February–March 2016). Patient demographics and treatment related data were obtained from electronic clinical records. All linezolid prescriptions were reviewed, carrying out and registering pharmacy interventions. The results were compared with evidence observed in published guidelines and the literature.

Results 53 patients treated with linezolid were found (66 years (30–95)), 60% were men. Average treatment duration was 10.4 days (median 8 days, treatments longer than 90 days excluded). Indications were: 30% skin infections, 22.6% peritonitis, 18.8% pneumonia, 7.5% prosthesis infections and 7.5% meningitis. 51% of cases were unlabelled indications. 26.4% were empiric treatments (<5 days), and 28.3% longer than 14 days (labelled treatment duration). Infectious diseases (32%) and critical care units (34%) were the most prescriber services. Microbiological samples were obtained in 90.6% of patients (39.5% Staphylococcus spp, 18.7% Enterococcus spp). Only gram negative bacteria were isolated in 6 patients (3 following treatment). 3 patients treated for more than 7 days had no samples. Adverse drug reactions did not lead to drug withdrawal in any patient. 7 patients (13%) developed thrombocytopenia (average 15.7 days of linezolid (5–35)), 2 anaemia and 1 liver enzyme elevations. 15 drug interactions were detected and followed clinically.

Conclusion Most uses of linezolid in our hospital were according to the hospital protocols and were highly supported by bibliography and clinical evidence, although they were not authorised by the drug data file or FDA. The issues identified for future pharmacy interventions were intravenous to oral switch (although not registered, it was considered too long), and treatment de-escalation (microorganisms sensitive to other drugs were isolated without antibiotic change). Pharmacists have contributed in a multidisciplinary team to optimise linezolid use, especially in the detection of drug interactions, drug adverse effects and validation of prescriptions of linezolid, in each case considering infection and causal microorganism.

No conflict of interest