UTI in Children

Doses are oral and for adults unless otherwise stated. Visit the Health Products Regulatory Board website or the printed Irish Medicines Formulary for drug SPCs, dosage, contraindications, interactions, or IMF/BNF/BNFC/MIMS. See guidance on dosing in children for quick reference dosage/weight guide. Letters indicate strength of evidence range from A+ (systematic review) to D (informal opinion). Statins can interact with some antibiotics and increase the risk of rhabdomyolysis. Amiodarone and drugs which prolong the QT interval can interact with many antibiotics. Many antibiotics increase the risk of bleeding with anticoagulants. Please refer to our Drug Interactions Table for further information.


  • 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 information about UTI Infections in Children


Treatment Dose TX Duration
Lower UTI trimethoprim 3 days
OR cephalexin 3 days
OR nitrofurantoin 3 days
OR amoxicillin
(if susceptible)
3 days
Upper UTI co-amoxiclav

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

7-10 days

Paediatric Algorithm

Patient Information

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 2017

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