Answer
Seek urgent advice for fever or shivering, back or flank pain, blood in the urine, pregnancy, rapidly worsening symptoms, or no improvement within 48 hours.
Sources for this answer
- NHSNHS · NHS medicine guidance
- Cystopurin 3g granules for oral solution — Current selected SmPCemc · Summary of Product Characteristics
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.