Brief Answer:
No fixed time, usually days to a few weeks

Detailed Answer:
Hello and welcome.

Thank you for writing in.

This depends entirely on the size of the stones ma'am. Smaller stones can take from a few days to weeks to pass with the help of medication (eg. alpha-blockers), plenty of fluids, and mild pain management medication (as they can cause a slight amount of pain while passing; so the answer to your second question is yes, they can cause some pain while passing. But, once a stone reaches the bladder, it usually passed within 24-48 hours.

Whereas bigger stones, usually cannot pass by themselves and require surgery and other procedures for removal.

I hope this information helps ma'am. Please feel free to write back to me for any further clarifications.

Best wishes.

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