symptom of kidney stones : What Happens

A kidney stone begins as a tiny piece of mineral in the kidney. When the urine leaves the kidney, it may carry the mineral out, or the mineral may stay in the kidney. If the piece of mineral stays in the kidney, over time more small pieces of mineral join it and form a larger kidney stone.

Most stones leave the kidney and travel through the urinary tract when they are still small enough to pass easily out of the body. No treatment is necessary for these stones. Larger stones, however, may become stuck in the tubes that carry urine from the kidney to the bladder (ureters). This can cause pain and possibly block the urine from flowing to the bladder and out of the body. The pain often becomes worse over 15 to 60 minutes until it is severe and constant. The pain may ease when the stone no longer blocks the flow of urine, and it often goes away when the stone passes into the bladder. Medical treatment is often necessary for larger stones.

The smaller a stone is, the more likely it is to exit the body (pass) on its own. About 90% of stones smaller than 5 mm(0.2 in.) and about half the stones 5 mm(0.2 in.) or larger pass on their own.1 You need more than home treatment for only 10% to 20% of stones.1
The average time a stone takes to pass ranges between 1 and 3 weeks, and two-thirds of stones that pass on their own pass within 4 weeks of the symptoms appearing.2, 1
Almost half of all people who get kidney stones will get more stones within 5 years unless they take preventive measures.3 When you have kidney stones several times over a period of years, the length of time between stones tends to get shorter. It is not possible to say who will have more stones in the future and who will not.

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