Possible Interaction: Sodium Fluoride and Calcium Supplement

“Previous studies demonstrated that a Ca pre-treatment greatly increases salivary F from a subsequent NaF rinse.”

“As the bioavailability of sodium fluoride (NaF) can be impaired by concomitant absorption of calcium , both drugs have to be ingested separately.”

“Pre-incubation of CA with 25 mM NaF changed CA to a Mn(2+)-dependent form with higher PTP activity.”

“Other schedules were studied as well, such as EC NaF tablets taken 1 hour after or 3 hours before the administration of calcium supplements.”

“The results were as follows: (1) When NaF is accompanied by calcium , the fluoride peak level is lower and delayed. (”

“It is speculated that since NaF (greater than 10 mM) can complex with extracellular Ca++, and thus reduce free Ca++ concentration required for O2- generation, a NaF-dependent increase in cAMP may restore cytosolic free Ca++ by mobilizing intracellular stores of Ca++.”

“Prolonged osteoblast life span was the most likely explanation for the increased mean trabecular thicknesses and trabecular bone volumes seen in patients with osteoporosis, when treated with sodium fluoride plus calcium supplements or daily injections of parathyroid peptide hPTH 1-34.”

“We also found that calcium reduced enzyme stimulation by forskolin and the GTP analog, guanyl 5'-yl imidodiphosphate [GMP-P(NH)P] in a dose-related manner and that activation by NaF was less sensitive to inhibition by calcium.”

“This enzymatic activity is strongly stimulated by NaF and 5'-guanylimidodiphosphate, is slightly stimulated by epinephrine, norepinephrine, isoproterenol, and prostaglandin E1 and is inhibited by calcium.”

“In contrast, subsequent studies showed that administration of sodium fluoride by peritoneal lavage decreased the amount of calcium removed by this procedure(5).”