16 mm is a big calculus... We sometimes use medicines to dissolve the stone only if patient is asymptomatic n stone small.. However results not guaranteed

There is no non surgical treatment for gallstones. In case of any symptoms she will need surgery that is laparoscopic cholecystectomy. Even if she is asymptomatic at present do remember that even silent gallstones may result in complications like jaundice, pancreatitis, empyema, etc. Silent gallstones may also become symptomatic during pregnancy.

[ ] Hi if there is no upper abdominal pain / post meal fullness / discomfort / upper back pain , then you don't require surgery. This is asymptomatic gall stone. In case you develop any of above symptoms then you require surgery. There is no any medicines in present world to dissolve gall bladder stone. Laparoscopic approach is gold standard for gall bladder removal. You can read my article on Practo- Gall bladder stone.Feel free to ask any further quary.