Right kidney stone 12mmx8mm is not considered serious, but it may cause severe lower back and abdominal pain, and may also lead to urinary tract obstruction, causing complications such as hydronephrosis. Right kidney stone 12mmx8mm belongs to the size of large kidney stones. Usually, they cannot be discharged by themselves and may get stuck in the ureter, causing irritation and damage to the ureter, which may cause severe lower back and abdominal pain, hematuria, frequent urination, and other symptoms, and bring great pain to the patient. Stones may also block the ureter, causing urine to be unable to drain downward, causing hydronephrosis, which can cause irreversible damage to the kidney in severe cases. Therefore, when it is determined that the right kidney stone is 12mmx8mm, you should actively cooperate with your doctor and undergo lithotripsy treatment to expel or remove the stone as soon as possible to avoid causing serious complications.