Cholesterol gallstone-dissolving agent

The answer is d, (Hardman, pp 934-935.) Chenodeoxycholic acid (chenodiol) and ursodiol have proved to he effective in some patients with cholesterol gallstones. Lovastatin lowers blood cholesterol levels but has no effect on gallstones. Methyl tertiary butyl ether and a new agent, monoctanoin, are infused directly into the common duct and will dissolve gallstones. 

Although few studies have been carried out into the physiological actions of limonene as a solvent, it has been demonstrated that a solvent /(-limonene preparation, injected directly into the biliary system, can dissolve or disintegrate the retained cholesterol gallstones in humans (Igimi et al., 1976 Schenk et al., 1980). Also, when used as a solvent, it enhances the percutaneous absorption of drugs such as antiinflammatory agents (Okabe et al., 1994). 

Schenk, J., Dobronte, Z., Koch, H. and Stolte, M. 1980. Studies on tissue compatibility of rf-limonene as a dissolving agent of cholesterol gallstones. Z. Gastroenterol. 18(7) 389-394. 

A commercial emulsifying agent, glyceryl monooctanoate (monooctanoin), has been found to be an excellent solvent for cholesterol [278]. In vitro it dissolved mixed cholesterol gallstones more than twice as fast as did sodium cholate solutions which have been used as infusions for dissolution of retained cholesterol bile duct stones. Monooctanoin has also been tried by T-tube infusion in an attempt to effect direct dissolution of stones. Cholesterol solubility and dissolution kinetics are enhanced (Fig. 4.39). Monooctanoin infusions were well tolerated and some or all stones in 10 out of 12 patients were removed by dissolution by biliary tract infusion of monooctanoin over periods ranging from 4 to 21 days. 

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