How long it takes to pass a kidney stone depends largely on its size.
If needed, specialist procedures are available to either break up a stone or have it removed surgically.
For stones measuring 5 to 10 mm, the passage rate ranges from 25% to 53%.
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Symptoms generally develop when a kidney stone passes into a ureter.
Of those lodged mid-ureter, roughly 60% will pass spontaneously.
Medical expulsive therapy (MET) may be prescribed for stones over 5 mm.
This involves the use of drugs calledalpha-blockers, which relax the smooth muscle in the ureter.
Alpha-blockers are most effective in the spontaneous passage rate.
For stones under 5 mm, there is still a benefit with alpha-blockers, but less.
If the stone has not passed after four weeks, more aggressive treatments may be recommended.
Stones over 10 mm are far less likely to pass on their own and may warrant immediate intervention.
The same may apply if you have hydronephrosis, which can lead to kidney damage if left untreated.
In such cases, three specialist procedures are commonly used, as follows.
The best candidates are people with stones under 10 mm.
For this procedure, you will lie on a padded table on a machine called alithotripter.
The shockwave generator will then be positioned over your abdomen.
An X-ray or ultrasound will pinpoint the stone’s location.
A series of shock waves strong enough to fragment the stone are delivered.
ESWL takes around one hour to complete.
Upon completion, you might return home and pee out the broken fragments in your urine.
Some recovery time may be necessary to rest and manage any discomfort.
The only medication used is a mild anesthetic to help numb the abdomen.
The stone is then either manually snared and removed or broken into pieces with a laser and removed.
Performed undergeneral anesthesia, the procedure usually takes one hour to complete or three hours at the most.
If the stone cannot be removed with PCNL, a more extensive surgical procedure called opennephrolithotomymay be performed.
This involves making a larger incision to directly access and remove the stone from the kidney.
Once the stone is expelled, the pain will almost immediately cease.
Sweating, restlessness, and nausea are common.
Summary
The time it takes to pass a kidney stone depends largely on its size.
Stones under 6 mm in diameter can pass in eight to 22 days.
Those over 6 mm may take a month or longer and often need treatment.
Drinking plenty of water can help speed up the passage of a stone.
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