Causes of smelly, cloudy urine

When you drink less fluid, urine becomes more concentrated and its odour may become stronger; dehydration can also make it look darker or less clear. Certain foods, supplements and medicines can alter smell without causing illness. Cloudiness may come from crystals, mucus or cells. A urinary tract infection can cause cloudy, strong-smelling urine with burning, urgency or frequent urination. Pain in the side or back, fever, chills, nausea or feeling markedly unwell can suggest infection higher in the urinary system, including a kidney infection.

Notice when the change began and whether it follows reduced drinking, a new medicine or a particular food. Drink fluids regularly unless a clinician has told you to restrict them. Do not use leftover antibiotics, because the correct treatment depends on the cause and a urine test may be needed. Arrange a clinical assessment if the smell or cloudiness persists, or if burning, urgency or frequent urination develops. A clinician may check a urine sample and ask about pregnancy, medicines and previous urinary problems.

Seek prompt medical care for fever, chills, pain in the back or side, vomiting, visible blood in the urine, or worsening pain. These features can occur with a kidney infection and should not be managed by waiting at home. Seek urgent help if you feel faint, confused or severely unwell, or if you cannot keep fluids down. Pregnant people, children, older adults and people with kidney disease or a weakened immune system should seek advice early when urinary symptoms appear.

Could a urine test identify an infection or another cause? Which symptoms would mean the infection has reached the kidneys? Should any of my medicines, supplements or fluid restrictions be considered?