poor aqueous solubility of the drug and/or its metabolites.high renal excretion of drug and/or its metabolites.past and/or family history of urolithiasis.Risk factors Patient-related risk factors However it seems that patients with a prior history of 'conventional stones' are at greater risk of developing the drug-induced form than those patients without a prior history of stone formation 1. In the USA excessive self-medication with the over-the-counter medicine guaifenesin, an expectorant (often combined with ephedrine), has resulted in hundreds of additional cases of stones.

In the Middle East and parts of Asia, ceftriaxone (a third-generation cephalosporin) has been a clinically-significant risk factor for drug-induced stones. Of course the specific agents and the time periods may be fairly specific to this laboratory, however the importance of protease inhibitors as major lithogenic agents has been observed in other datasets from around the world.

1987-1996: indinavir, triamterene, sulfonamides.

1977-1986: triamterene and glafenine ( NSAID).

It was found that the drugs most commonly responsible for stone formation changed over time and the 40-year period could be subdivided into four phases: One of the largest studies reviewed all 70,253 calculi referred to a specialist laboratory for stone analysis in France from 1977 to 2016 1. No sex predilection has been reported.Īll studies of the prevalence of drug-induced calculi are limited by the inherent difficulty that the calcium-containing calculi which form secondary to a patient's medication are indistinguishable from other calcium-containing calculi as there are no differences at all in their composition, size or morphology. Conversely when stones actually contain the iatrogenic agent they are easier to separate out (albeit with sophisticated analysis) from other non-drug-induced calculi. Overall drug-induced urolithiasis accounts for 1-2% of all renal calculi 1.

Renal calculus treatment