Alkaline soap (lithontriptic base)
synthetic
MECHANISM CLAIMED
Chemically dissolves the stone inside the bladder, regardless of the stone's composition, when taken as part of the powder, decoction, and pills.
MECHANISM ACTUAL
Modern nephrology confirms alkali therapy in general can dissolve existing pure uric-acid (urate) stones by raising urine pH, but has no dissolving action on calcium-containing stones such as calcium oxalate -- the type that makes up the largest share of cases. A 2013 professional urological assessment attributes this same alkali mechanism specifically to the soap in Stephens's recipe; no source in this bundle independently confirms her particular undosed preparation achieved therapeutic urinary alkalinization in any patient. Even granting that attribution, a single alkaline ingredient could narrow, real efficacy against one stone type at most; it could not be the universal solvent for 'the stone' that the recipe was marketed as.
INTERVENTIONS USING IT
NOTES
Soap — an alkali — was the one ingredient common to both the decoction and the pills in Joanna Stephens’s 1739 recipe, alongside calcined eggshells, snails, honey, and assorted seeds and herbs. A 2013 professional urological assessment singles it out as the recipe’s one component with a real, if narrow, chemical action, attributing it the ability to dissolve a uric-acid (urate) stone already formed; modern nephrology independently confirms alkalis in general can do this by raising urine pH, though not for a calcium-oxalate stone, one of several distinct stone types later distinguished by Alexander Marcet’s chemical analyses. Stephens’s medicine was marketed and paid for as a general “solvent for the stone,” not as a treatment for one stone type; the underlying chemistry of alkali dissolution was never capable of supporting that broader claim.