Clinical Outcomes in Gentamicin Prescribing and Monitoring: National Audit

Project status

Co-Gent is closed to recruitment and is now in the data analysis phase. We look forward to giving results as soon as possible but please bear with us while we analyse the data.


A multicentre audit and service evaluation of extended-interval gentamicin prescribing and monitoring (GPM), to assess current practice, audit practice against local policies, and describe clinical outcomes using different strategies in GPM.


Gentamicin is an antibiotic with a wide spectrum of activity versus Gram-negative bacteria, and a rapid bactericidal effect. However, gentamicin has a narrow therapeutic index, with significant risks of nephrotoxicity and ototoxicity.

Historically, multiple daily dosing strategies were employed during gentamicin therapy. In the 1990s, ‘extended’ daily dosing regimens replaced multiple daily dosing, with studies showing comparable effectiveness and reduced nephrotoxicity. A number of different protocols for dosing and monitoring arose simultaneously at different centres. There are very few studies directly comparing these approaches, with no consensus on which one(s) are the most effective, safe and easy to follow.

An audit of gentamicin in the northwest of England revealed a wide variety of practice across NHS Trusts, with GPM according to Trusts’ local policies being well below the audit standards. Local variation in practice may contribute to suboptimal GPM; this is compounded by regular rotation of junior doctors, nurses and pharmacists between organisations. There is no clinical guideline for GPM that is widely used in the UK. This national audit seeks to understand current practice and compare clinical outcomes of different protocols for GPM. The results would help to inform the development of a national guideline for gentamicin prescribing.


Any infection doctor, antimicrobial pharmacist or junior doctor or medical student with an interest in infection specialties. Contribution of data will make one investigator per centre eligible for authorship on the manuscript written by the project leads at the end of the audit. All participants will receive audit certificates.


Sites were invited to express interest from April 2021.

For any questions, please email

Project Documents

The Protocol is available here.

The Audit Data Collection Tool is available here.

The Data Collection Guide is available here.

Project lead: Dr Raqib Huq, ST5 Infectious Diseases & Medical Microbiology, Pennine Acute Hospitals NHS Trust

Consultant lead: Dr Suganya Reddy – Consultant Microbiologist, Lancashire Teaching Hospitals NHS Foundation Trust

Pharmacy Lead: Miss Sabina Bashir, Principal Antimicrobial Pharmacist, Lancashire Teaching Hospitals NHS Foundation Trust

Pharmacy Lead: Mrs Rebecca Clark, Highly Specialist Pharmacist, Lancashire Teaching Hospitals NHS Foundation Trust