Where to go urologist or nephrologist? case for 5.5mm kidney stone non obstructive?is it big or can pass by drinking water?

Urologist: Average person "passes" a 5 mm stone 1/2 the time: bigger the stone, the less likely it will pass. Alpha blockers (tamsulosin) have been shown to improve spontaneous passage, but the best estimate correlates with hx of "passed" stones. Important to strain all urine/save any stones - the best way to know if one passes, and to have it analyzed for composition - for recommendations for prevention.

Stone in kidney: This size stone may pass on its own if you drink 4-5 liters of fluid per day. Be sure to include at least one quart of lemonade or lemon extract added to water. If you use ReaLemon extract, add 5 teaspoons to each quart of water you drink. This will help. Minimize salt. Minimize animal protein. Push the fluids daily.