What should you know about diabetes and kidney stones?

When blood glucose is high, the kidneys may pass more glucose and water into urine. This can contribute to fluid loss, especially when thirst, vomiting or illness also limits drinking. More concentrated urine can make it easier for mineral crystals to form, although diabetes alone does not explain every stone.

A kidney stone is a solid crystal that may remain in the kidney or move into the tube carrying urine to the bladder. Its movement can cause flank or abdominal pain, blood in the urine, nausea, or painful urination. A symptom does not establish the cause; examination and testing may be needed.

Keep taking diabetes medicines as prescribed unless a clinician gives you different instructions. Check your glucose as advised, drink fluids if you can do so safely, and record pain, urine changes, vomiting and any fever. Do not force large amounts of fluid if you have been told to restrict fluids or have a heart or kidney condition.

Arrange a GP consultation for persistent pain, urinary symptoms, repeated stones, or difficulty keeping fluids down. Assessment may include a urine test, blood tests and imaging such as an abdominal ultrasound. A clinician can also review hydration, diabetes control, medicines and the type of stone if one is passed.

Seek urgent medical help for severe or worsening flank or abdominal pain, fever or chills with urinary symptoms, repeated vomiting, marked weakness, confusion, or difficulty passing urine. In someone with diabetes, illness and dehydration can disturb glucose control quickly, so urgent advice is appropriate when you cannot drink, are passing very little urine, or your glucose readings are concerning.

Ask whether your symptoms fit a stone or another urinary problem, which tests are suitable, how to manage fluids with your diabetes plan, and whether any medicine needs temporary adjustment during illness. Ask what warning signs should send you to urgent care and whether a recovered stone should be analysed.