Dissolution of calcium fluoride tablets in vitro and bioavailability in man

The dissolution rate of CaF2 tablets in vitro and the degree of F absorption in vivo after tablet intake in man were investigated. 50% of total F was released in 0.1 N HCl after 45 min whereas virtually no release was seen in H2O or in 0.2 M PO4-buffer pH 6.8. In spite of the modest release of F in simulated gastric juice in vitro no F absorption as judged from the plasma fluoride concentration curve was seen within 6 h after intake of 4 mg F as CaF2 tablets.