New research has revealed that tolvaptan doesn’t just hinder cyst growth and kidney function decline in people with autosomal dominant polycystic kidney disease (ADPKD). In a 2020 study, published in the Clinical Journal of the American Society of Nephrology, researchers at Bern University Hospital in Switzerland studied 24-hour urine compositions from 38 patients treated with tolvaptan and 87 untreated patients from the Bern ADPKD registry. From these compositions, they found that tolvaptan may also prevent kidney stones.*

Encouraging findings

Hypocitraturia (low urinary citric acid excretion) and hyperoxaluria (too much oxalate in the urine) are the most common abnormalities that promote mineral mass deposits in people with ADPKD. Urinary abnormalities and increased kidney volume contribute to stone formation in up to 36% of ADPKD patients. 

The study team noticed significantly higher urine citrate and calcium excretion, drawing an association between tolvaptan use and lower urinary amounts of:

• Calcium oxalate (crystal-forming chemical and the most common cause of kidney stones) 
• Brushite (an unusual phosphate mineral causing large stones in some people)
• Uric acid

Tolvaptan was also associated with significantly higher gastrointestinal alkali absorption. Alkalis are crucial for balancing out acids in the body and help prevent mineral stone formation. 

*Persaud, N. (2020, July 15). Tolvaptan Lowers Kidney Stone Risk in ADPKD. Renal and Urology News. 

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