Editing Kidney stone disease (section)

== Prevention ==
Preventative measures depend on the type of stones. In those with calcium stones, drinking plenty of fluids, [[thiazide]] [[diuretic]]s and citrate are effective as is allopurinol in those with high uric acid levels in urine.<ref name=Fink2013>{{cite journal | vauthors = Fink HA, Wilt TJ, Eidman KE, Garimella PS, MacDonald R, Rutks IR, Brasure M, Kane RL, Ouellette J, Monga M | title = Medical management to prevent recurrent nephrolithiasis in adults: a systematic review for an American College of Physicians Clinical Guideline | journal = Annals of Internal Medicine | volume = 158 | issue = 7 | pages = 535–43 | date = April 2013 | pmid = 23546565 | doi = 10.7326/0003-4819-158-7-201304020-00005 | doi-access = free }}</ref><ref name=Qas2014 />

=== Dietary measures ===
{{See also|#Hypocitraturia|label1= Hypocitraturia}}
Specific therapy should be tailored to the type of stones involved. Diet can have an effect on the development of kidney stones. Preventive strategies include some combination of dietary modifications and medications with the goal of reducing the excretory load of calculogenic compounds on the kidneys.<ref name=Parmar2004 /><ref name=Goldfarb1999 /><ref name=Finkielstein2006 /> Dietary recommendations to minimize the formation of kidney stones include:
* increasing total fluid intake to achieve more than two liters per day of urine output;<ref name=AHRQ2012>{{cite journal |publisher=Agency for Healthcare Research and Quality |location=Rockvill, MD | vauthors = Fink HA, Wilt TJ, Eidman KE, Garimella PS, MacDonald R, Rutks IR, Brasure M, Kane RL, Monga M | title = Recurrent Nephrolithiasis in Adults: Comparative Effectiveness of Preventive Medical Strategies |journal=Comparative Effectiveness Reviews |number=61 | date = July 2012 | pmid = 22896859 }}</ref>
* limiting [[cola]], including sugar-sweetened soft drinks;<ref name=Fink2013 /><ref name=AHRQ2012/><ref name="FerraroTaylor2013">{{cite journal | vauthors = Ferraro PM, Taylor EN, Gambaro G, Curhan GC | title = Soda and other beverages and the risk of kidney stones | journal = Clinical Journal of the American Society of Nephrology | volume = 8 | issue = 8 | pages = 1389–95 | date = August 2013 | pmid = 23676355 | pmc = 3731916 | doi = 10.2215/CJN.11661112 }}</ref> to less than one liter per week.<ref>{{cite web |url=http://www.kidney.org.au/ForPatients/Management/KidneyStones/tabid/838/Default.aspx |title=What are kidney stones? |website=kidney.org |access-date=19 August 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130514122900/http://kidney.org.au/ForPatients/Management/KidneyStones/tabid/838/Default.aspx |archive-date=14 May 2013 |df=dmy-all }}</ref>
* limiting animal protein intake to no more than two meals daily (an association between animal [[Protein (nutrient)|protein]] and recurrence of kidney stones has been shown in men);<ref name=Taylor2006>{{cite journal | vauthors = Taylor EN, Curhan GC | title = Diet and fluid prescription in stone disease | journal = Kidney International | volume = 70 | issue = 5 | pages = 835–9 | date = September 2006 | pmid = 16837923 | doi = 10.1038/sj.ki.5001656 | doi-access = free }}</ref>
* increasing citrate, including from lemon and [[lime juice]];<ref name="Gul_2014">{{cite journal | vauthors = Gul Z, Monga M | title = Medical and dietary therapy for kidney stone prevention | journal = Korean Journal of Urology | volume = 55 | issue = 12 | pages = 775–9 | date = December 2014 | pmid = 25512810 | pmc = 4265710 | doi = 10.4111/kju.2014.55.12.775 }}</ref> citric acid in its natural form, such as from citrus fruits, "prevents small stones from becoming 'problem stones' by coating them and preventing other material from attaching and building onto the stones";<ref>{{cite web |title=Citric Acid and Kidney Stones |url=https://www.uwhealth.org/files/uwhealth/docs/pdf/kidney_citric_acid.pdf |archive-url=https://web.archive.org/web/20100705033118/http://www.uwhealth.org/files/uwhealth/docs/pdf/kidney_citric_acid.pdf |archive-date=2010-07-05 |url-status=live |website=uwhealth.org}}</ref> citrate inhibits the formation of kidney stones on all phases[[Nucleation|{{emdash}}nucleation]], growth and aggregation{{emdash}}by raising the limit at which oxalate remain stable, slowing oxalate crystal growth, and notably, reducing crystal aggregation within the [[kidney tubules]];<ref name="pmid26439475"/>
* increase alkaline load by consuming more fruits and vegetables (because uric acid crystals form in acidic environment);<ref name="Gul_2014"/>
* reducing sodium intake is associated with a reduction in urine calcium excretion.<ref name="pmid38931286">{{cite journal |vauthors=Balawender K, Łuszczki E, Mazur A, Wyszyńska J |title=The Multidisciplinary Approach in the Management of Patients with Kidney Stone Disease-A State-of-the-Art Review |journal=Nutrients |volume=16 |issue=12 |date=June 2024 |page=1932 |pmid=38931286 |pmc=11206918 |doi=10.3390/nu16121932|doi-access=free }}</ref>

Maintenance of dilute urine by means of vigorous fluid therapy is beneficial in all forms of kidney stones, so increasing urine volume is a key principle for the prevention of kidney stones. Fluid intake should be sufficient to maintain a urine output of at least {{convert|2|L|USoz|lk=on}} per day.<ref name=Qas2014>{{cite journal | vauthors = Qaseem A, Dallas P, Forciea MA, Starkey M, Denberg TD | title = Dietary and pharmacologic management to prevent recurrent nephrolithiasis in adults: a clinical practice guideline from the American College of Physicians | journal = Annals of Internal Medicine | volume = 161 | issue = 9 | pages = 659–67 | date = November 2014 | pmid = 25364887 | doi = 10.7326/m13-2908 | doi-access = free }}</ref> A high fluid intake may reduce the likelihood of kidney stone recurrence or may increase the time between stone development without unwanted effects.

Calcium binds with available oxalate in the [[gastrointestinal tract]], thereby preventing its absorption into the [[Circulatory system|bloodstream]]. Reducing oxalate absorption decreases kidney stone risk in susceptible people.<ref name=Heaney2006 /> Because of this, some doctors recommend increasing dairy intake so that its calcium content will serve as an oxalate binder'''.''' Taking calcium citrate tablets during or after meals containing high oxalate foods<ref name=Tiselius2003 /> may be useful if dietary calcium cannot be increased by other means as in those with lactose intolerance. The preferred calcium supplement for people at risk of stone formation is calcium citrate, as opposed to calcium carbonate, because it helps to increase urinary citrate excretion.<ref name=Finkielstein2006 />

Aside from vigorous oral hydration and eating more dietary calcium, other prevention strategies include avoidance of higher doses of supplemental {{nowrap|vitamin C}} (since [[ascorbate]] is metabolized to oxalate) and restriction of oxalate-rich foods such as [[List of common leaf vegetables|leaf vegetables]], [[rhubarb]], [[Soybean|soy products]] and [[chocolate]].<ref name=Taylor2004 /> However, no randomized, controlled trial of oxalate restriction has been performed to test the hypothesis that oxalate restriction reduces stone formation.<ref name=Tiselius2003 /> Some evidence indicates [[magnesium]] intake decreases the risk of symptomatic kidney stones.<ref name=Taylor2004 />

=== Urine alkalinization ===
The mainstay for medical management of uric acid stones is [[Alkalinity|alkalinization]] (increasing the [[pH]]) of the urine. Uric acid stones are among the few types amenable to dissolution therapy, referred to as [[Lysis|chemolysis]]. Chemolysis is usually achieved through the use of oral medications, although in some cases, intravenous agents or even instillation of certain irrigating agents directly onto the stone can be performed, using antegrade [[nephrostomy]] or [[retrograde ureteral]] catheters.<ref name=Knudsen2007 /> [[Acetazolamide]] is a medication that alkalinizes the urine. In addition to acetazolamide or as an alternative, certain dietary supplements are available that produce a similar alkalinization of the urine. These include [[alkali citrate]], [[sodium bicarbonate]], [[potassium citrate]], [[magnesium citrate]], and [[bicitrate]] (a combination of citric acid monohydrate and sodium citrate dihydrate).<ref>{{cite journal | vauthors = Cicerello E, Merlo F, Maccatrozzo L | title = Urinary alkalization for the treatment of uric acid nephrolithiasis | journal = Archivio Italiano di Urologia, Andrologia | volume = 82 | issue = 3 | pages = 145–8 | date = September 2010 | pmid = 21121431 }}</ref> Aside from alkalinization of the urine, these supplements have the added advantage of increasing the urinary citrate level, which helps to reduce the aggregation of calcium oxalate stones.<ref name=Knudsen2007 />

Increasing the urine pH to around 6.5 provides optimal conditions for [[Dissolution (chemistry)|dissolution]] of uric acid stones. Increasing the urine pH to a value higher than 7.0 may increase the risk of calcium phosphate stone formation, though this concept is controversial since citrate does inhibit calcium phosphate crystallization. Testing the urine periodically with [[nitrazine]] paper can help to ensure the urine pH remains in this optimal range. Using this approach, stone dissolution rate can be expected to be around {{convert|10|mm|in|1|abbr=on}} of stone radius per month.<ref name=Knudsen2007 />

==== Slaked lime ====
[[Calcium hydroxide]] decreases urinary calcium when combined with food rich in oxalic acid such as green leafy vegetables.<ref>{{cite web |url=https://www.researchgate.net/publication/287536542 |title=Effect of addition of calcium hydroxide to foods rich in oxalic acid on calcium and oxalic acid metabolism {{!}} Request PDF<!-- Bot generated title --> |access-date=6 March 2021 |archive-date=7 November 2021 |archive-url=https://web.archive.org/web/20211107061411/https://www.researchgate.net/publication/287536542_Effect_of_addition_of_calcium_hydroxide_to_foods_rich_in_oxalic_acid_on_calcium_and_oxalic_acid_metabolism |url-status=live }}</ref>

=== Diuretics ===
One of the recognized medical therapies for prevention of stones is the [[thiazide]] and [[thiazide-like diuretic]]s, such as [[Chlortalidone|chlorthalidone]] or [[indapamide]]. These drugs inhibit the formation of calcium-containing stones by reducing urinary calcium excretion.<ref name=Cutler2007 /> Sodium restriction is necessary for clinical effect of thiazides, as sodium excess promotes calcium excretion. Thiazides work best for renal leak hypercalciuria (high urine calcium levels), a condition in which high urinary calcium levels are caused by a primary kidney defect. Thiazides are useful for treating absorptive hypercalciuria, a condition in which high urinary calcium is a result of excess absorption from the gastrointestinal tract.<ref name=Coe2005 />

=== Allopurinol ===
For people with [[hyperuricosuria]] and calcium stones, [[allopurinol]] is one of the few treatments that have been shown to reduce kidney stone recurrences. Allopurinol interferes with the production of uric acid in the [[liver]]. The drug is also used in people with [[gout]] or hyperuricemia (high [[Serum (blood)|serum]] uric acid levels).<ref name=Cameron1987 /> Dosage is adjusted to maintain a reduced urinary excretion of uric acid. Serum uric acid level at or below 6&nbsp;mg/100&nbsp;mL is often a therapeutic goal. Hyperuricemia is not necessary for the formation of uric acid stones; hyperuricosuria can occur in the presence of normal or even [[hypouricemia|low serum uric acid]]. Some practitioners advocate adding allopurinol only in people in whom hyperuricosuria and hyperuricemia persist, despite the use of a urine-[[alkalinizing agent]] such as [[sodium bicarbonate]] or [[potassium citrate]].<ref name=Knudsen2007 />