What should you know about caffeine and kidney stones?

Kidney stones form when substances in urine become concentrated and crystallise. Caffeine can increase urine production in some people, especially when intake is high or the body is not accustomed to it. The main concern is losing the habit of drinking enough water, rather than assuming that one coffee caused a stone. Stone risk also depends on stone type, diet, medicines and personal medical history. A stone may cause flank or abdominal pain, painful urination, nausea or difficulty passing urine.

Make water your main drink and spread fluids through the day unless a clinician has given you a fluid restriction. Do not use coffee or energy drinks as your only source of hydration. If caffeine seems to worsen discomfort, reduce it gradually and note changes. A GP Consultation can assess your symptoms, medical history and urine concerns. An Abdominal Ultrasound may be considered when imaging is needed to look for a stone or blockage.

Seek urgent medical help for severe or persistent flank pain, fever or chills, repeated vomiting, blood in urine, or difficulty passing urine. These symptoms can signal obstruction or infection and should not be managed by simply drinking more. Arrange a review for recurring pain, painful urination or a history of stones so prevention can be tailored.

Ask what type of stone is suspected, how much fluid is suitable for you, whether caffeine should be limited, and whether testing or imaging is needed.