Fluoride salts and derivatives

Observational studies

The effects of intermittent low-dose fluoride combined with continuous calcium supplementation on bone mass and future fracture events have been evaluated in 64 men with idiopathic osteoporosis [ ]. They were randomized to intermittent treatment with monofluorophosphate plus calcium or calcium supplementation alone for 3 years. Seven of the patients given fluoride had leg pain. In most cases the pain, which was generally confined to the ankle, disappeared during the fluoride-free month. In a few cases, the fluoride-free month had to be prolonged to 7 or 8 weeks before the symptoms subsided. During fluoride therapy, two patients had mild epigastric symptoms and one had diarrhea, but these appeared to be related to calcium; seven of the patients who were given calcium alone complained of epigastric discomfort and two had diarrhea. All the adverse events were mild to moderate and transient, and none led to discontinuation of treatment.

A 3-year, open study [ ] has been performed with monofluorophosphate in 60 patients under 75 years old (average age 62 years, body weight 42–84 kg, height 148–174 cm) with established postmenopausal vertebral osteoporosis and a lumbar T score lower than − 2.5 BDM (measured by dual-energy X-ray absorptiometry) and at least one vertebral fracture diagnosed according to WHO criteria [ ]. The patients had taken hormone replacement therapy for an average of 2 years. Patients with inflammatory rheumatic diseases and those who were taking other medications that can modify bone metabolism, such as calcitonins, bisphosphonates, vitamin D, or anabolic agents, were excluded. There were adverse events in 19 patients, 10 of which were probably due to the monofluorophosphate or calcium components, three with gastrointestinal symptoms and seven with leg pain. The other nine adverse events were probably due to the hormone replacement therapy component: three with vaginal bleeding, four with breast tenderness, one with “heavy legs”, and one with increased body weight. All the adverse events were of mild or moderate intensity and resolved spontaneously; none required withdrawal of treatment.