What should you know about nephrolithiasis?

A stone may remain in the kidney without symptoms, or move into the tube carrying urine to the bladder. Movement or blockage can cause waves of pain in the side or back, pain that travels toward the groin, nausea, or blood in the urine. [Painful Urination](/symptoms/painful-urination/) and [Difficulty Passing Urine](/symptoms/difficulty-passing-urine/) can occur when the lower urinary tract is affected. Low fluid intake and [Dehydration](/conditions/dehydration/) can contribute to concentrated urine, but symptoms alone cannot identify the stone's size or position.

Arrange a medical assessment to confirm the cause and check for obstruction or infection. A clinician may review the pain pattern, urine, kidney function, and imaging such as an [Abdominal Ultrasound](/treatments/diagnostics-and-screening/abdominal-ultrasound/). Drink fluids according to medical advice; forcing large amounts can be unsafe when urine flow is blocked or vomiting prevents drinking. Use only pain relief that is suitable for your health and medicines, and consider a [GP Consultation](/treatments/consultations-and-assessment/gp-consultation/) if symptoms are new or recurring.

Seek urgent help for severe or uncontrolled [Flank Pain](/symptoms/flank-pain/), fever or chills with urinary pain, repeated vomiting, inability to pass urine, faintness, or feeling suddenly very unwell. A blocked urinary system with infection can deteriorate quickly. Pregnancy, one functioning kidney, known kidney disease, or a child with suspected stone symptoms also warrants prompt clinical advice.

Ask whether imaging is needed, whether the stone appears likely to pass, which pain medicines are safe for you, how much fluid is appropriate, how to collect a passed stone, and which symptoms mean you should return urgently.