What causes urinary tract infection?

The urinary tract includes the kidneys, ureters, bladder and urethra. Most infections begin when bacteria travel through the urethra to the bladder. Dehydration can mean less urine is available to flush the urinary tract and may contribute to infection, although drinking more water cannot treat an established infection. Trouble emptying the bladder, urinary blockage, catheter use and changes in the urinary tract can also make infection more likely. Burning when urinating, frequent small amounts, urgency or lower abdominal discomfort can occur with a bladder infection. Fever, chills or pain in the back or side may suggest that infection has reached the kidneys.

Contact a clinician if symptoms suggest a urinary infection, particularly during pregnancy, in a child, or when you have kidney problems or a weakened immune system. Drink fluids normally, rest and do not use leftover antibiotics. A clinician may test a urine sample and prescribe treatment when appropriate. Take prescribed medicine exactly as directed and seek advice if symptoms do not improve.

Seek urgent medical care for fever with urinary symptoms, shaking chills, pain in the back or side, vomiting, confusion, marked weakness, or inability to pass urine. These features can indicate a more serious infection or a blockage requiring prompt treatment.

Ask whether a urine test is needed, which treatment is suitable, how to manage symptoms safely, and what warning signs should bring you back for review.