UTI in Children

Doses are oral and for adults unless otherwise stated. Visit the Health Products Regulatory Authority (HPRA) website for detailed drug information (summary of product characteristics and patient information leaflets). Dosing details, contraindications and drug interactions can also be found in the Irish Medicines Formulary (IMF) or other reference sources such as British National Formulary (BNF) / BNF for children (BNFC). See guidance on dosing in children for quick reference dosage/weight guide. Refer to drug interactions table for detailed drug interactions for all antimicrobials. Note extensive drug interactions for clarithromycin, fluoroquinolones, azole antifungals and rifampicin. Many antibiotics increase the risk of bleeding with anticoagulants.

Note additional warnings for clarithromycin and fluoroquinolones

Comments from Expert Advisory Committee

  • Refer children <3 months to specialist.
  • Send MSU in all for culture & susceptibility. If ≥3 years, use positive nitrite to start antibiotics. Refer children <3 years post UTI for imaging.
  • For antibiotic dosing details, and doses for older children, please refer to Irish Medicines Formulary.
  • Click here to view the paediatric algorithm on Urinary Tract Infection


Take local susceptibility data into account to guide your treatment where possible
Treatment Dose TX Duration
Lower UTI cefalexin 3 days
OR nitrofurantoin* 3 days
OR trimethoprim* 3 days
Upper UTI cefalexin

See guidance on dosing in children for quick reference dosage/weight guide.

7-10 days


7-10 days

*safe in penicillin allergy

Patient Information

Visit HPSC Information Leaflets pages for the General Public, (MRSA, CRE, etc)

We recommend patients use the website developed by HSE/ICGP/IPU partnership www.undertheweather.ie for tips on how to get better from common infections without using antibiotics, what you can do for yourself or a loved one and when to seek help.

Reviewed November 2020

antibiotics banner