Temocillin is a beta-lactam antimicrobial with exclusively gram-negative spectrum of activity, but excluding P.aeruginosa. It is only available as an intravenous (IV) formulation.
Common gram negative bacillus species (not exhaustive):
These are only reported as "I" or "R" (see below).
N.B. Pseudomonas aeruginosa is never susceptible to temocillin.
In antimicrobial susceptibility results, temocillin is never reported as “S” = susceptible at standard dosing, but only as “I” = susceptible at increased exposure, or “R” = resistant.1
Table 1: Antimicrobial susceptibility
Susceptibility result | Interpretation | Appropriate treatment for infection caused by the reported organism? | Antimicrobial dosage |
I = susceptible at increased exposure | High likelihood of therapeutic success, if exposure to the agent is increased | Yes | Use dosing regimens in Table 2 as recommended by EUCAST1,2 |
R = resistant | High likelihood of therapeutic failure even when there is increased exposure | Do not use agent to treat this organism | Not applicable |
Table 2: Temocillin dosing adjusted for renal function
Creatinine Clearance (ml/min) | IV Temocillin Dosing Regimen |
>60 | 2g 8-hourly |
40 - 60 | 2g 12-hourly |
20 - 40 | 2g immediately, then 1g 12-hourly |
<20 | 2g immediately, then 1g 24-hourly |
References
1. European Society of Clinical Microbiology and Infectious Diseases. EUCAST Clinical Breakpoints Table, Version 11. European Committee on Antimicrobial Susceptibility Testing, Jan 2021. Available at: https://www.eucast.org/fileadmin/src/media/PDFs/EUCAST_files/Breakpoint_tables/v_11.0_Breakpoint_Tables.pdf
2. Renal Drug Database; Temocillin (login required via Knowledge Network). Reviewed 28/10/24.
3. NHS Ayrshire & Arran Code of Practice for Medicines Governance, Section 9(b) “Off label” Use of Medicines (link only active if accessing via NHS network).
Guideline reviewed | April 2025 |
Page updated | August 2025 |