Fluoride concentrations in saliva after single oral doses and their relation to plasma fluoride

The saliva and plasma fluoride (F) concentrations following intake of different doses of fluoride tablets were studied in six subjects. There was a close relationship between saliva F and plasma F and the ratio was 0.64 +/- 0.01 (s.e.). The plasma half life of F was 4-16 h. This results indicate that saliva F may be a useful substitute for blood sampling in studies concerning the pharmacokinetics of fluoride.