MODEL RELEASED. Patient lying on a hospital bed. Boy feeling sick from kidney stones lying on a hospital bed. Kidney stones are chemicals that have crystallised out of the urine forming a stone, or stones, somewhere along the urinary tract. The main symptoms are pain and nausea. Immediate treatment might include painkillers, medication to prevent sickness or intravenous fluids. Photographed at the Royal Hospital for Sick Children, Edinburgh, UK.